Chapter 7: Outdoors

Marijuana Horticulture: The Indoor / Outdoor Medical Grower’s Bible

by Jorge Cervantes

Much of the information that pertains specifically to outdoor cultivation is in this chapter. Many of the subjects in this chapter are covered in great detail in other chapters of the book. References to these chapters are made in the appropriate places.

Outdoor growing is more popular than indoor growing in countries with lax cannabis laws. The reason is simple – sunshine is free; lights and electricity cost money.More people grow outdoors than indoors for this simple reason.

Cannabis is a strong plant that can be grown successfully almost anywhere. As long as you pay attention to security, virtually any growing area can be altered enough, often with little effort, to grow a healthy crop.

Do your research before planting. Read garden columns and talk to local growers about the best time to plant and grow tomatoes or similar vegetables, then plant accordingly. Also inquire about common pests and insects. Collect publications on local growing conditions. These are often available at nurseries or through your local department of ministry of agriculture.

You can grow anywhere. For example, one of the first guerilla crops I planted was on a freeway on-ramp in a city in Northwestern US in the 1970s. I planted seedlings in a clay soil in a blackberry infested environment in late June. I gave the plants a single application of time release fertilizer. By late September there were short little female plants with dense little buds to smoke. The harvest weighed in just under a pound of fragrant but leafy little buds. Everybody called it “homegrown”.

My first big guerilla crop was planted and harvested in the California foothills. I hiked up one of the many canyons carrying a 3.5 hp engine that weighed 30 pounds, pus the pump (another 30 pounds) and the plumbing connections that made it attach to a 2 inch inlet and a 1.5 inch outlet. Schlepping four, 30 gallon plastic garbage cans to act as reservoirs, 10 foot lengths of pvc pipe, and 200 feet of hose was a challenge!

After many trips up the canyon, I harvested six pounds of Colombian and Mexican bud. The quality was fair, but I harvested early and had the only fresh buds in town in mid-September.

In “the good old days”, rural real estate for sale in California often advertised the number of marijuana growing holes that had already been amended.

Now Park Rangers carry guns and have the authority to arrest suspected growers. Latin mafias have also moved into the National Forests installing illegal immigrants with guns to grow and defend large patches of guerilla grass. The War on Drugs has turned much of America into an unsafe place to live and grow.

Australia, Canada, much f Europe, and many other parts of the world are significantly different; growers can plant in their backyards, greenhouses, or in remote locations with little fear of arrest.


Selecting the right strains for your climate is just as important as finding the perfect location. It is a good idea to grow several different strains with different finishing times to spread out the work and drying over the course of time. If you grow a spring crop, you can harvest much of the season.

Hash Plant, Aghani, Hindu Kush, etc, are great varieties that finish mid- to late- August. The yield and potency are quite high, but the fragrance is high too! These strains are for experienced growers. They need lots of intense sunlight and must be watered from below, not from above with rain. These varieties start to bud when the days are long and the sunlight is intense. The buds fatten up quickly on plants with short, squat growth habit. Rain followed by hot sunny days can foster mold, which could decimate the crop in a short time. Leaf has been dried, cured buds the size of softballs that were packed with mold. They were thrown away. To avoid mold problems, he suggests harvesting when about 10 percent of the pistils have died back. Even heavy dew can cause a moldy disaster!

Early Pearl, Early Queen, Early Riser, etc, Manitoba Poison, and similar strains finish from ate-August to early-September at latitude 49 north. They are potent and yield a little better than the plants listed above. They grow from six to nine feet tall and are quite bushy. Most of these strains are mold resistant and easy to grow – excellent choices for novices or growers with little time to look after their plants.

Mighty Mite, Durban Poison, Jack Herer, etc, finish mid- late- September. The yield and potency are very god, and the odor is not too intense. All the plants grow a huge, dominant main cola with several large terminal buds on main branches. They may need trellising to avoid broken branches. Topping appears to increase yield. These strains are fairly low-maintenance, but the more love you give, the more they return. These plants grow well if left alone until mid-September and have a good harvest as long as they do not dry out or fall over. Mighty Mite is another favorite.

Blueberry, White Widow, White Rhino, Super Silver haze, Pure Power Plant, etc, tend to finish mid- to late-October. Yields and potency are very high! They do not smell a lot while growing, but that changes when they are cut! They grow seven to ten feet tall and yield heavily. They require some attention to get the best crop. Super Silver Haze and Pure Power Plant can be a bitch to grow because they often develop mold near harvest when the weather is damp. however, a mild to moderate frost tends to bring out some nice (purple)colors. They all do well outdoors but grow even better indoors.

Skunk #1, Northern Lights #5, Big Bud, and pure or nearly pure sativas finish from late-ctober to early-November. Sometimes sativas do not finish if the weather cools too much and snow comes. One year, on November 15th, the first snowfall had to be shaken off at harvest! About 50 percent of the pistils had died back. Skunk #1 is extremely smelly; the wind can literally carry the skunk scent for a mile. All of the plants in this group have large to huge yield capable or producing several pounds each. Big Bud yields an enormous amount; the bottom branches must be tied or staked to avoid breaking from bud weight. Potency is superb in all plants in this category except for Big Bud.

All plants grow tall. Big Bud and Skunk #1 grow 10-14 feet tall. Northern Lights are often taller. A few sativas can grow to 20 feet!

Fungus can become a problem with these late-flowering plants. They withstand rain and light frost well; many can take a few light snowfalls. After all, they grow like weeds!


outdoor grow shows are dominated by climate, soil, and water supply whether you are planting in a remote mountain patch, a cozy garden in your backyard, or on your balcony.

Microclimates are mini climates that exist within larger climates. Maps are available of these areas. Many maps such as the United States Department of Agriculture (USDA) Hardiness Zone map, detail limited climactic boundaries. The map divides North America into ten zones plus zone 11 to represent areas that have average annual minimum temperatures above 40F and are frost free. Look into detailed microclimate maps for your grow zone.

temperature, rainfall, and sunlight vary widely across the globe, providing unique growing environments and countless microclimates. Look for specific information for your climate at local nurseries and in regional gardening books and magazine or through the department of agriculture in your area.

Coastal climates like those found in the Northwestern United States, British Columbia, Canada, Northern Coastal Europe, and the United Kingdom, etc, are cool and rainy. Annual rainfall most often exceeds 40 inches and can be as high as 100 inches! Winter blows in early in these areas bringing a chilling rain and low light levels. The more northern zones experience shorter days and wet cold weather earlier than the southern zones. Growing outdoors here is challenging because the temperature seldom drops below freezing, which contributes to larger insect populations. Some of these cold coastal rainforests are packed with lush but invasive foliage and fungal growth brought on by the cold and damp.

Clay soil with a low pH is common in moist coastal zones.

Start Clones or Seedling Indoors

Get a jump on the season by starting clones and seedlings under lights indoors. Move small containerized plants into heated greenhouses to start hardening-off. Transplant to a backyard or secure guerilla patch once they have become hardened-off and are more resistant to environmental stress.

Beat the cold; start seedlings and cuttings indoors and move them into a heated greenhouse in March or April. A 400-watt HP sodium lamp on a timer can augment the less-intense natural light of early spring. Seedlings and clones will need at least 14 hours of artificial and natural light per day until plants are transplanted outdoors.

Alpine mountain climates are cold much of the year. Freezing temperatures, mineral heavy acidic soil, and wind top the list of grower concerns.

Summer temperatures in the mountains can dip to 30F or lower in the summer, at as low as 2000 feet elevation. Temperatures below 50F virtually stop growth, and temperatures below 40F can cause foliage tissue damage in many strains. Low temperatures cause stress in plants and a reduction in harvest weight. On the other hand, plants in high alpine climates tend to produce more resin and 10-20 percent more THC than those in lower gardens.

You can help your plants deal with mountain stress by backfilling planting holes with a mix of peat moss, soil , polymer crystals, and slow-acting layers of organic fertilizer.

Cold wind causes moisture loss, and plants dry out quickly. This causes stress which can weaken pants and leave them open to attack by disease and insects.

Col mountain environments, like those in Switzerland or the Rocky Mountains of North America, usually experience first frost in September and last frost during May.

Spring and fall months are rainy with a dry period in July and August. Cold rains in the fall can cause mold. Planting early-maturing strains helps avoid weather problems.

tropical climates are generally warm to hot and humid. Rainy and dry seasons vary by location. Most jungle and tropical climates have daily rains. Protecting flowering females from rain with a greenhouse will help avoid bud mold and other problems. The closer to the equator, the less deviation there is between the length of days and nights. Extra hours of artificial light are necessary to keep plants in the vegetative growth stage. Tropical sativa strains are often favored in these regions because they are acclimated and require little special care.

Nighttime temperatures and humidity are often high. In fact, extended nighttime temperatures above 85F will cause plants to stop growing. Nighttime cooling could be necessary to keep pants growing well.


Soil is one of three main types and all shades of gray and brown in between. Soil is the product of millions of years of geology.

Clay soil, also known as “heavy soil” or “adobe” in North America, is common in coastal areas and is very widespread inland. It is difficult to work with.

Clay soils hold water well and provide slow, even drainage. Clay soils are slow to warm in the spring, but hold warmth well into autumn when sunlight is fading. The density of clay does not allow for proper air circulation, and root growth is inhibited.

Prepare cay soil at least a month before planting, adding lots of compost and manure. Clay soils can hold water too well, which can smother roots. Adding organic matter will lighten the heavy soil, thus creating air pockets, improving drainage, and promoting root growth.

The month delay gives the manure a chance to col so it wont burn the plants.

Use low sodium manure that contains few salts. Cows are given sodium nitrate to make them gain weight, but that same salt in their manure can lock up nutrients available to the plants, stunting their growth.

Do not be fooled by anyone who suggests adding sand to break up clay soil. Sand and clay create cement; add straw to make bricks!

One gardener had a backhoe operator excavate a pit 10 feet square by 2 feet deep, built a 2-foot retaining wall around it, then filled it will 400 cubic yards of river loam. This expensive, laborious soil transformation paid off in one outstanding crop after another over years.

A long term option is to annually till in compost, manure, and other organic amendments.

Raised beds are an excellent option for clay soil. Till the clay when it is damp and workable, and add manure / compost in heaps; plant directly in the mounds.

Pile subsoil in a ring around the plant, making a bowl to catch rain water.

Sandy soil is found near large bodies of water, in deserts, and in many inland areas. It is comprised of small, medium, and large particles and is easy to till even when wet. Plants can achieve excellent root penetration. Sandy soil feels and looks gritty.

Sand is easy to work and warms quickly in the spring, but it does not hold fertilizer well, especially when over-watered – the nutrients wash out. Compost helps bind the large particles providing food and air circulation, but in hot climates the organic matter decomposes rapidly and is soon consumed by bacteria and other soil organisms.

For best results keep sandy soil cool, retain moisture with mulch, and cultivate often, adding additional compost. Winter season cover crops will hold moisture and prevent runoff while retaining life in the soil.

Loam soil has all the advantages of clay and sand; it holds moisture and water like clay but is quick to warm and has god drainage and a work-friendly structure like sand. It is the perfect growing medium.

Most soils are a combination of sand and clay. Silty loam falls in between and feels almost greasy when rubbed in your hand, though it is less slippery than clay. The ultimate soil for growing plants is loam found in ancient river bottoms and lake beds where sedimentary soil builds up. It is dark, fertile, and crumbly in the hand.

Forest soils vary greatly in pH and fertility. The needles and deadfall from the trees usually make the soil acidic

Most of the forests remaining in North America and Europe are on hillsides. Flat land is used for farming,recreation, and urban sprawl.

Long needle pines grow in poor soils such as those found in mountainous and tropical regions. They have deep rots to look for all the elements in the soil. When a layer of humus evolves, short needle conifers dominate. The roots on these trees spread out on the surface to search for nourishment and bury roots to anchor it in place.

Jungles are usually low-growing, hot, moist, and dense. The soil is shallow and alive. The hot weather makes ll foliage that falls to the ground decompose quickly. Often nutrients are available to plants, but the soil does not have a chance to build density. Layers of tropical soils can be very thin. However, through much of Mexico and Central America volcanic eruptions brought much rock and minerals to the surface. Mountain valleys and lowlands are full of alluvial plains that are packed with nutrient rich soil.

Grasslands often have wonderful soil that recycles nutrients. Sunshine is likely to be good, but detection could be a problem in wide open spaces. Plant in areas that are protected from wind and curious eyes.

Mountain soils are often very rich in minerals but lack humus. Alpine valley hold the best alluvial-plain soil that is the product of volcanic rock erosion. Hillsides are generally less fertile, and soil must be amended to grow a good crop.

Bog soils are moist and spongy. Bogs are filled with vegetation and often have very rich soil. They present a perfect place to grow individual plants. Cut a square yard of moist sod from the ground, turn it over, and plant. Marsh ground supplies sufficient water on its own. Add a bit of time release fertilizer during transplanting and another handful of flowering formula during a check-up in early August.

Most often, it is easiest to change or amend native soil that will produce scrawny plants. You can grow in containers so you can control all factors, but just remember, containers require more maintenance.

Worms work wonders with soil. Grow your own crop of worms in a worm bin. Worms grow and reproduce in layers of food scraps, soil, and manure. They produce worm castings, an excellent fertilizer / amendment or compost tea ingredient.

Soil and water pH levels are exceptionally important. Cannabis does best with a soil pH of about 6.5.

Raising alkaline levels is somewhat easier than raising the acid level. If your soil is too alkaline, 1.2 oz of finely ground rock sulfur per square yard of sandy soil will reduce soil pH by one point. Other types of soil will need 3.6 oz per square yard. Well-decomposed sawdust composted leaves, and peat moss also hep to acidify soil and lower pH.


Hardpan is a condition whereby a layer of soil beneath the soil surface is hard and impenetrable to both water and roots. Caliche is a hardpan common in the southwest USA. It consists of a layer of calcium carbonate (lime) located below the topsoil. The texture of caliches varies from granular to solid cement-like rock and can be from a few inches to many feet thick.

To plant in any hardpan area, you must bore through it t provide drainage. An auger will work to bore a hole, but a pick and shovel are practical, too. All other planting techniques remain the same. Discard the hardpan bored out of the hole and replace with compost or high quality garden soil.

Prepare Soil

help reduce the stress by growing seedlings in tall containers which will produce a strong rot system and a plant that has a better chance of surviving in tough conditions. Adding water-absorbing polymers in the plant mix is an excellent defense against desiccation, too. The crystals expand up to 15 times when watered, making moisture available to the roots for longer periods of time. Slow-release crystals will allow an extended period between watering. This is very helpful if your patch is in a remote location that you cannot visit often.

Mountain areas can have poor soil and will need to be improved before planting for best results. Dig holes at least 18 inches wide by 18 inches deep for each plant. Place a handful of blood meal on the bottom and three to four inches of soil on top of it before transplanting the cuttings or seedling, then water heavily. A little effort preparing the planting holes will result in healthier plants and a heavier harvest.

n an incline, planting holes must be terraced into the hillside and be large enough to catch runoff water. Dig extra gullies to channel runoff to growing plants, and make a “dish” around the plants t hold water.

Plants remain smaller in rocky terrain but often go unseen because they are grown where no on expects to see them.

Clay forms an excellent underground planting container. After a good rain, dig large planting holes. Fill holes with lots f good dirt and compost. Backfill in layers; for example, fill a three foot deep hole with an eight inch layer of steamed bone-meal and soil. The balance is made up of a thin layer of topsoil mixed with a rich compost-manure-straw mixture, rock phosphate, and seaweed meal. Mound compost and soil about a foot above ground level. It will settle during growing season.

Prepare to plant by digging a big hole and placing boards at the bottom to stop downward water flow. Add compost, peat moss, coco peat, good soil, organic nutrient, polymers, and dolomite lime – all will help soil hold water – then top with a concave bowl of soil that will catch rain and irrigation water.

Raised Beds

Raised beds are wonderful for growing in the backyard. Cultivation and weed control are easier, and soil quality is simpler to maintain.

Build a raised bed on top of clay soils. Planting in a bed raised six to eight inches eliminates the necessity of trying t dig in clay while providing the early warmth and good drainage clay lacks. Pants can be put into the ground two weeks to a month early and may even produce an early spring crop.

One friend plants on tp of the compost pile. He plants six, 12 inch tall clones into three t four inches of good soil that is on top of a two- to three-foot high compost heap. By the time the roots penetrate into the compost, it has cooled enough that the roots are safe from burning. He places a portable greenhouse over the plants. The compost keeps plants warm wile the structure protects foliage. This works exceptionally well to coax a spring harvest.

Another grower prepares a vegetable garden by dumping three cubic yards of finished compost and manure with a dose of dolomite lime into a raised bed, then he roto-tills and plants. When the vegetables are growing well, he transplants hardened-off clones to blend in alongside vegetables.


Mulch attract and retains soil moisture and smothers weeds. Mulch is a layer of decomposing foliage, straw, grass clippings, weeds, etc. and/or paper, rocks, plastic, etc, laid around plants.

native foliage is an excellent and convenient mulch. My favorite mulch is dry grass clippings, which are free. Fill your backpack with grass clippings before every trip to the patch. Always pile the much as high as you can because it biodegrades over time.

Rock or rock dust makes excellent mulch. Use rock mulches where they are readily available. They become hot to touch on sunny days, but they still protect the soil from evaporative moisture loss.

Newspaper or brown paper shopping bags make excellent mulch. Slightly wet paper is easier to work with and less likely to blow around. Inexpensive and readily available, newspaper layers should be at least six pages thick, before adding a soil or mulch covering to hold it in place.

Woven weed barriers or strips of scrap carpet let water drain but will not let the weed grow through. Cover these barriers with rock or bark chips.

Cover the entire garden bed with black plastic and cut holes thru which seedlings are planted. A soaker hose can be laid underneath the plastic to irrigate,. Make sure to cut large enough holes so that plant stems do not touch the plastic. Black plastic gets very hot during the day but actually warms the soil very little. When a young, tender plant stem touches the hot, black plastic, it will literally cook the soil line.


Plants can be fertilized enough to make them respond and grow well within a temperature range of 60-90F, reasonable humidity, adequate sunshine, and moderate wind.

Be sparing with fertilizer the first month after transplanting. Depending upon fertilizer, application could as often as every watering or as seldom as every week or two.

If fertilizing with every watering, you may need to dilute the food to half strength or less until you figure out the proper dosage.

Fertilize with a mild, soluble flowering solution for germination and seedling growth. Change to a high nitrogen formula during the vegetative stage and back to a super-bloom when the long nights induce flowering.

Use grandular concentrated fertilizers or organic fertilizers that are lightweight and not bulky to transport and store.

Build organic soils using different natural substances. Always use the most readily available form of the element.


Clean rainwater is the best for irrigation. To make sure it is not too acidic and harmful to plants, take the pH and parts per million (ppm) reading from collected rainwater before using.

Sodium-heavy water builds up in the soil causing slow growth and shorter plants with smaller leaves. At low levels, sodium appears to benefit plants and may even make up for potassium deficiency, but too much leads to “sodium stress”. Roots lose the ability to absorb water and other nutrients and will dry out even with heavy watering. It is very important to test your water for sodium and other dissolved solids and take appropriate action if the reading reaches more than 50 ppm. Sodium is more of a problem when growing in containers than when growing in well drained soil.

Local farmers of the Department of Agriculture have information about water solids in your area, and many areas have low-cost, state-certified labs that can test your water for you.

Often, if the sodium content is below 300 ppm, a good flushing every month will keep sodium and other salts from building up to toxic levels.

There are several easy, inexpensive options to improve water quality. Irrigate seedlings, clones, and mother plants with rainwater to dilute dissolved solids.

Flush container gardens with three quarts of water for each dry quart of soil. Water once with tap water and always afterwards with tap water augmented with ammonium sulfate.

Clean tap water by filing barrels and setting 2-3 feet off the ground. Add ammonium sulfate to settle out the sodium, then siphon water from the top of the barrel, refilling after each watering to allow the chlorine to evaporate. Chlorine, like sodium, is beneficial in small amounts. It is essential to the use of oxygen during photosynthesis and is necessary for root and leaf cell division. But too much chlorine causes leaf tips and margins to burn and leaves to turn a bronze color.

Empty the barrel periodically, and scrub out residues and sediments. Clean rainwater is an excellent choice for irrigation. Collect runoff by placing a barrel under a downspout.Mix the rainwater with barrels of tap water to dilute the dissolved solids. Roofs and terraces can accumulate trash, which will pollute the otherwise clean rainwater. Covering you8r catch-barrel will prevent evaporation and keep out trash.

Sodium, calcium, and magnesium can be harmful in the soil, too. Excess calcium, for example, keeps the pH level too high and blocks uptake of several nutrients including iron and potassium. Fertilizer with chelated iron will counteract this problem. To much magnesium creates rapid uptake of trace elements but does not usually cause a problem.

The fertilizer comes in liquid or wettable crystal form and can also be used in soil to alleviate problems caused by bad weather. Several commercial hydroponic fertilizer formulations for “hard” water are available and work very well.

Check the garden daily, if possible, and water when soil is dry one inch below the surface. Irrigate plants in the ground until they are completely wet.

Many different types of receptacles and reservoirs can store irrigation water. Use the biggest storage unit that you can manage you will always need more water. One good option for storing a lot of water is to dig a nice big hole and line it with a pond liner.


Pumps move water long distances and uphill. Pumps can be operated by hand, batteries, gasoline, gravity, and with pressure from moving water.

Gasoline powered pumps are reliable and can lift much water uphill quickly, but they are noisy. You can purchase a pump already attached to the motor or connect them yourself and mount them on board.

Noise is a major factor in starting up a small gasoline powered engine in the middle of a quiet mountainous area. An oversized muffler and small baffle will deaden most of the external sound.

Set up the pump so that the intake will be able to gather water easily. Make a small dam only if it is discreet.

Manual powered pumps require a lot of physical energy to operate and are impractical for moving a large volume of water uphill.

Siphoning water downhill will move a lot of water. Finding a water source above the garden is the key!

Lightweight hose will not disturb foliage. If you can find it in back, it will be more difficult to spot. Most garden hose is a bright green color!


The best way to control temperature outdoors is to plant in the right place. Normally hot temperatures are common during midday in full sun. Cannabis virtually stops growing at 85F. If you are planting in a hot climate, make sure plants receive filtered sunlight during the heat of the day. Also, plant them in natural breezeways so a breeze will cool them during the heat of the day.

You can create shade over your patch by bending tree branches and tying them in place.

Cold temperatures can be avoided by planting at the proper times – well after the last frost. Harvest before first frost.

A shade house covered with “shade cloth” (synthetic sun blocking material) or lath house, which is built from thin, narrow strips of wood, are great places to protect plants. Lath houses can provide 25 percent shade or more depending on the placement of the laths. Shade cloth is available in different meshes that filter out 10, 20, 30, etc, percent of the sunlight. Shade or lath houses are also a great place to pass summer days.


Wind is one of the strongest forces outdoors. Sustained wind will suck moisture from plants. Wind causes plants to draw moisture from the roots and shed it through the leaves in a defensive mechanism to regulate internal temperature and chemistry. It creates a prole if the water supply is limited.

For example, Southern Spain and other arid regions are subject to strong desert winds that transport abrasive sand and other particles. We call it “kalmia” in Spain because the grit is mixed with saline air from the Mediterranean. These winds can destroy crops. If your climate is plagued by such abrasive winds, protect plants with windbreaks. Wash foliage with plenty of water to remove the particles after windstorms.

Moderate sustained winds will dry out container – and field-grown crops within a few hours. Container crops suffer the most. For example, plants grown in five gallon containers on a terrace that receives full sun and constant moderate winds uses about two gallons of water daily! Indoors, the same plant would use 75 percent less water!

Plant in protected areas so the garden suffers little effect from strong wind.

Pests and Predators

Once your plants are in the ground, well-fed, and watered, check them weekly for pest and fungal damage. Inspect the top and bottom of leaves for stippling (small pots) from mites or damage from chewing insects and slugs and snails. First identify the pest, and then determine a curse of action.

Properly grown outdoor cannabis has few problems with pests.

Low tech, natural approaches to pest control work well. A few large pests like caterpillars and snails can be hand picked from the foliage. Caterpillar populations can be reduced at the source by installing bat houses. Resident bats will eat moths and decrease the numbers of chewing caterpillars. Birds will eat caterpillars too, as well as aphids and other insects. Attract birds with suet, bird houses, baths, and feeders but cover tender seedlings and clones with wire or nylon mesh to protect them from birds too! Ladybugs and praying mantis are good options for insect control and can be purchased from nursery supply stores.

barns owls eat mice, gophers, and voles, but are hard to come by in the city. If you are lucky enough to have them nearby, take advantage of their ability to eat plant pests. On the other hand, some rodents, like moles and shrews, help your garden by dining n slugs, insects, and larvae.

Marigold cultivars of the Tagetes erecta and T. patula species, will repel nematiodes, also known as eelworms, from the soil for two to three years if they are planted in an infested area and then tilled under. Just planting them in an area doesn’t accomplish anything. Numerous tests indicate that they do not have an effect on insects above the ground.

Frogs and Toads

Frogs and toads eat insects and slugs. The frogs will need a water source, while toads are more terrestrial. Large snakes in the garden will eat gophers, squirrels, and mice as well as the moles and shrews. Snakes can give you a good scare if you come across one unexpectedly! The snake will also want to eat your frog. Plan carefully before committing to any mini-predator solution to pest infestation.


Although most birds are welcome guests in most gardens, there are some that can make quick work of tender seedlings or new clones.

The most effective way to keep birds from freshly planted seed and transplants is to cover plants with plastic wire or plastic netting. When installing the netting, make sure it is securely fastened around the perimeter of plants so hungry birds do not get underneath.

Deer and Elk

Deer and elk love newly formed growth f cannabis pants. In addition, they may destroy crops by trampling them. Elk are somewhat of a problem, and deer are a problem!

A cage around pants is the best deterrent. But remember, the wire may be easy to spot if it is not discreet in color. Deer are repelled by the smell of blood and human hair. Pace handfuls of dried blood meal in cloth sacks and dip in water to activate the smell. Hang sacks from a tree to discourage dogs and other predators from eating them.

Handfuls of human hair can be placed in small cloth sacks and hung fro a fence or tree branch as a deterrent. Do not use your own hair; it could turn into evidence for police! Scented soaps have repelled deer from some gardens. But if deer are very hungry, the smell of blood meal, human hair, scented soap, or anything else will not deter them.

Always urinate in several locations around the perimeter of the garden so animals take your presence seriously. Some growers save urine all week and disperse it at regular visits to their patch.

Deer easily bound over eight foot fences. A good deer fence is eight feet tall with the top foot sloping outward, away from the garden at a 45 degree angle. Electric fences and large dogs are also excellent deterrents.


pocket gophers are small burrowing rodents that eat plant roots and foliage. These herbivores find fleshy roots a real treat and occasionally attack cannabis. Should a family of gophers move int your area, get rid of them as son as possible. Females can bear up to five litters of four to eight offspring a year. A family of gophers can clean out a large garden in a matter of weeks.

The only sure way to get rid of gophers is by trapping. There are several gopher traps available, including ones that capture them alive. It will take some skill before you are regularly able to catch gophers with traps. You must avoid getting human scent on any part of the traps. if gophers sense the human odor, they will simply push soil over the trap to spring it or render it otherwise ineffective. Traps are put in gopher runways and so don’t need to be baited.

A fence f poultry wire f 0.5 inch hardware cloth buried one foot deep and standing 3 feet above ground will exclude gophers. Line panting holes with chicken wire before filing with soil. Driving metal sheets around the perimeter f planting holes will also prevent gopher damage.

Mice and Voles

Mice and voles can chew back from around the base of cannabis plants. If this is a problem, keep mulch a foot away from plants, and install a wire mesh around the trunks. Mice and voles make nests in large piles of mulch, and they are attracted to stored water. Cover all water sources to exclude them, but keep in mind that they might chew through the container if water is super scarce.

The best mouse deterrent is a cat that is serious about hunting. Mousetraps also work well on smaller populations. Removing a large number of mice with traps can be tedious and unpleasant.

Do not use poison! Scavenger animals will eat the dead rodents and may become poisoned themselves.


Moles are minor pests. They are primarily insectivores that eat cutworms and other soil grubs, but their tunnels may dislodge cannabis roots.

Repel moles with castor plants or gopher plants Euphorbia lathyris. Castor bean eaves and cantor oil, as well repel moles if put into their main runs.

Blend two tablespoons of castor oil with three tablespoons of dish soap concentrate and ten tablespoons of water. Mix in a blender. use this as a concentrate at the rate of two tablespoons per gallon of water. Apply as a soil drench directly over mole holes.

Barrel traps, scissor traps, and guillotine traps are effective and kill moles instantly.


Rabbits eat almost anything green, and they multiply like rabbits! Repel rabbits with a light dusting of rock phosphate on young leaves of dried blood sprinkled around the base f plants. Manure tea sprayed on leaves and soil may keep them from dining on your plants. Rabbits find plants dusted with hot pepper or a spray of dilute fish emulsion and bone meal repulsive. There also are a number of commercial rabbit repellents, but be wary of using these on consumables!

A dog will keep rabbits in check, but the only surefire way to keep rabbits out of the garden is to fence them out with one inch poultry wire. The poultry wire should be buried at least six inches in the ground to prevent burrowing and rise two to three feet above ground. Wrap trunks with a wire mesh to keep rabbits from chewing bark in winter and early spring.

Rogue Pollen

Rogue pollen from commercial hemp farms and wild or cultivated males can threaten sinsemilla cannabis grown outdoors or in greenhouses. Undesired pollen can drift from a few feet to hundred of miles to pollinate flowering females and cause them to grow seeds.

Large clouds of pollen blow across the Mediterranean Sea from the Riff Mountains in Morocco dropping pollen on Spain and Portugal. In fact, local weather reports always include the cannabis pollen statistics. The reports are directed at people with allergies but are also used by marijuana growers.

Make inquiries into air quality including cannabis pollen. Some growers develop “allergies” in order to get the most information from officials. Researching wind direction relative to your crop and closet hemp plants will help you select sites less likely to be contaminated.

Wind-shadows (large divots in a hillside) protect plants from wind and anything it brings along.

If rogue pollen is a problem, plant early crops or late crops that flower before or after male plants. Usually June and July are the worst months for pollen, but it could also spill into August.

You may be able to grow indoors until the industrial hemp is done flowering and males are no longer releasing pollen, or plant out of the wind pattern. If pollen is severe, keep plants in a greenhouse. Cover the intake opening with a mist towel – humidity makes pollen unviable. Put one edge of the towel in a bucket of water to wick moisture. Wetting down the exterior of the greenhouse will also help incapacitate any wild pollen.

Backyard Growing

Lucky growers who live in countries that tolerate cannabis can safely plant a crop in their backyard and give their garden the tender loving care it deserves. You can pay close attention to your plants’ soil, water, and nutrient needs. Growing cannabis in your flower and vegetable garden is ideal because you can care for all your plants at the same time.

Prepare soil in the fall; remove weeds and dig planting holes or garden beds. Turn it over and make sure it has plenty of amendments. Always put a heavy layer of mulch on any soil that will be planted! A 12-inch-plus layer of mulch will keep soil elements intact as well as attract moisture. Bare soil loses most of its valuable topsoil to erosion during winter months.

In the spring, mulched amended soil should be well-mixed and ready for planting. You can transplant cannabis seedlings r clones in the garden just like you would tomatoes. If your soil is poor, or you didn’t begin cultivation in fall, dig large holes, three feet in diameter by three feet deep, and fill with your best compost, potting soil, or planting mix. Otherwise, break up the top six to eight inches of soil in a six-foot radius to provide room for root branching.

Bury containers in a garden bed so they do not stick out too much. They can be easily moved indoors at night or to a remote location.

Terrace Growing

Growing in containers on a terrace, balcony, or roof is very rewarding. A small sunny location, good genetics, containers, and good soil are the basic needs.

Your gardening techniques will depend on location of the grow show. City building rooftops, terraces, and balconies tend to be windy. The higher the garden, the more wind. Wind dries plants quickly.

Patio gardens are most often protected from strong winds and strong sunlight.

An automatic watering system is often a good idea in such gardens to ensure they receive adequate water, especially if you are gone for a few days.

Pots will also need to be shaded from sunlight. Ht sun beating down on pots cooks plant roots.

Even with adequate security, the standard issues of water, soil, and fertilizer apply. For a successful crop, daily maintenance is essential during hot and windy weather.

Guerilla Growing

Guerilla growing, a term coined in the early 1970s, requires strategy, time, and most often, physical prowess. Depending upon your location and local laws, clandestine guerilla growing in remote locations could be your only option.

Location and security are the main concerns for a guerilla grower. Choose a location that has limited public access. Check regulations for hunting and recreation, and think of who might be using the area: hunters, mushroomers, other marijuana growers, hikers, dirt-bikers, Boy Scouts, etc. Select a remote site unlikely to be used casually.

Look for a site that already has big green stands of vegetation. Marijuana is a vigorous plant with a large root system, and a flowering female will stand out if surrounding vegetation dies back before harvest. Stands of thorny blackberry bushes, ferns, and meadow grass are good options.

Prepare your marijuana patch up to six months before planting. Remove green vegetation in the fall for a spring garden. Clear a few patches to allow sufficient sunshine, cut back roots of competing plants, and till planting holes two to three feet square. If possible, allow amended soil to sit for a months or longer before planting. Remote locations are hard to visit on a regular basis, so proper planning and preparation is important. If your home and guerilla gardens are similar, you can pant an indicator crop like tomatoes as a backyard guide to your hidden plants’ condition.

Ample water is an important factor for site selection. If you cannot count n rainfall, locate your garden near a water source that does not dry up in the summer. Doing so will make watering easier and cut the chance of being spotted hauling water. Exclusive access by bat will reduce risk of discovery, but make sure your plants cannot be seen from the boat. Many people use waterways and explore land bordering rivers.

Plants need a minimum of five t six hours of sunshine a day. Scout sites in the winter and try to visualize how the trees will cast shadows during the summer months. Remember that the sun takes a higher path in the spring and summer. Five hours of direct midday sun per day is essential for acceptable growth. More is better. Rocky terrain, hillside terraces, and grasslands all receive good amount of sunlight.

Wind patterns will affect your garden and influence where pants are located. Do your homework. Research average wind direction and force. Windbreaks protect plants from heat and water loss.


A secure location is the number ne concern for most guerilla growers. Indoor growers can rent an apartment, house, or warehouse in the name of another person to avoid discovery. Guerilla gardens planted on public land risk detection by hikers, fishermen, or other outdoor enthusiasts. Remember, they are interested in specific spots and recreation. They will not go out of their way t find your patch unless you lead them t it.

Choose a site that does not make your plants the focal point of the garden. Make everything blend into surroundings so there is virtually no trace of a grow show. hide cannabis among other plants that are of similar size and foliage. Stinging nettles camouflage cannabis well, and if you are unlucky enough to brush up against them, they seem to reach out and bite you, giving a burning sensation for about 20 minutes.

Park your vehicle in a discreet place away from the trailhead to your guerilla patch.

Be prepared with a believable story about why you are hiking around. Some possible ideas include bird watching, fishing, wildflower photography, etc. Make sure to have some props: fishing pole, camera, bird identification book, etc, to corroborate your story. Stay alert; this is risky business!

Some growers prefer to visit their patch late in the afternoon when the bulk of visitors are most likely to be in the forest. Now you will have plenty of time to complete tasks, and when the sun sets, you can return under the secure veil of twilight.

If you prefer to visit your grow show in the early morning when it is dark, a flashlight with a red or green lens helps your eyes adjust.

Always carry a cell phone t call for help or to communicate with a partner while at the patch. Turn the ringer off!

Prevent making a distinguishable path to the patch by taking a different route every visit. Walk on logs, rocks, and up stream beds to avoid detection. Rapid growth of native plants will erase any obvious trail. You can fertilize to assist in repair, but be careful with application as wild plants are easily over-fertilized. Remember in late summer and early fall, most native plants in dry climates will not regrow.

Bring growing supplies to the patch and stockpile them over time – PVC pipe, gasoline-powered pumps, water tanks, soil, bricks of coconut fiber, compost, etc. – and hide them discreetly. You can take a few things to the patch each time. Make these trips count; plan ahead.

Prevent the style, size, and sole pattern of your shoes from leaving discernible tracks that could lead thieves and cops to your patch. Your shoe print could be used as evidence against you if your patch is busted!

Camouflage plants by bending, pruning, or splitting the stem down the middle. Bending branches is the least traumatic and has more subtle effects on hormones, liquid flow, and physical shape. You can split the main stem down the middle and stretch the halves horizontally t create an espalier. Pruning produces the strongest effect because it removes the high concentrations of the hormones in the terminal buds and stimulates lateral growth. Pruning several main stems may make the plants less obvious but does not improve harvest. Think carefully about desired outcome before cutting.

Grow in sticker bushes or other unpleasant foliage such as poison oak, poison ivy, stinging nettles, etc, to discourage intruders. Look for bushes that are dense and high enough to shelter the patch from view. This deters large animals or people from wandering in to the site. Protect yourself from these plants with a slick rain suit and gloves. Wash after each visit to remove irritating toxic oils and thorns.

Some growers plant where there are a lot of mosquitos or wasps, and at least one grower I know plants near a skunk den. The pungent spray keep people and animals at bay.

Some growers climb 30 feet or higher up into the tress to plant on stands in the canopy or use deer and elk stands as growing platforms.

Set up a pulley system to lift large containers and potting soil up to the platform. Install an irrigation hose from the base of the tree up to the planting area and arrange around the pots so you can perform weekly watering with a battery powered pump rather than climbing the tree. Find a partner to stand lookout when you are working in the canopy, and be sure to use safety lines. Do not overextend yourself. I used to climb trees for a living, and my hard and fast rule was to spend no more than four hours climbing per day. When you get tired, accidents happens. If you hurt yourself, you will not be able to care for your plants!

Drought Growing

If you do not have access to a water source, dry land crops are possible if the area gets at least one good rain every one to four weeks. In general, sativa strains have a bigger rot system than indica strains and are more drought resistant.

Plants pull water and nutrients from the soil. Acceptable soil will hold one inch of water per one square foot of area and grow a plant seven too eight feet tall with roots five feet across and six feet deep. Insufficient water results in small buds. A five-foot plant may produce only one to six ounces of smokable bud. By contrast, a plant in god soil with ample water will be more robust and yield two too ten times more than those in poor soil, making attention to soil and water quality essential.

An easy, inexpensive way to feed and water your plants is to cut a 3/16-inch hole in the bottom of a five-gallon bucket and fill with water and water soluble fertilizer.Place one bucket by each plant with the hole oriented near the stem. Buckets should be refilled every ten days during the hottest weather. You will be able to get through the summer with as few as four to six buckets of water. This is very inexpensive and the extra water and nutrients will really pay off when it is time to harvest.

Planting and Maintenance

Start clones off in rockwool, Jiffy, or soilless grow cubes for three weeks, and then transplant int four inch pots of organic soil mix. Water transplants heavily to encourage root growth. Grow under an HID or CF lamp for two weeks. harden-ff before moving outside into the garden or secret garden.

One grower I know keeps a stream of plants moving from indoors to his outdoor gardens. He plants the first crop of clones in three-gallon pots in a greenhouse, hardens them off, and moves them t their final location. The second crop is moved into the greenhouse when the first crop is moved out. He repeats this process three to four times during the season.

A complete low-maintenance setup is the goal for most guerilla growers. Loosen the soil, amend it, and throw in a handful of polymers to retain moisture. A thick layer of mulch, early in the year, will attract water, keep the soil cool, and prevent evaporation. Bury clones deep in the ground to promote a deep root system that will not require a lot of additional water.

Some growers transplant one foot tall clones with smaller root systems by removing the first few sets of leaves and burying the root ball deeper with only six inches of foliage left above ground. Rots will grow along the underground stem in a few weeks. Deep roots will create more self sufficient plants. This is of particular importance in extremely remote areas that are hard to get to and in the mountains where the rainfall may be sporadic.

Pest prevention is crucial for guerilla crops because the patch is to difficult to maintain every day of the week. It is easier to keep pests from attacking plants in the first place than to try and do damage control later.


Harvest before cold, damp, autumn weather sets in. This weather causes fungus-botrytis (bud mold) and powdery mildew. Many plants can take a short mild freeze. But if the temperature stays below freezing for more than a few hours, it could kill plants. Pay close attention to weather forecasts and apply the information to the microclimate where your plants are growing. Be ready t harvest quickly if weather dictates.

Law enforcement can force a harvest, too. Limit potential discovery by hunters, hikers, and cops by harvesting at night. Find out when police r rangers are in the area, and plan to be there at a different time. Police scanners that pickup local police activities can come in handy for determining their location.

Take a sharp pocket knife and a backpack to haul your crop incognito. If you are harvesting more than one variety, put them in separate bags or wrap in newspaper before they go in the backpack.

Determine a believable story to explain your presence in the area, including proximity to the garden, should you be discovered. Offer nothing, explain little, and keep it simple so you don’t slip.

Extending Seasons

Many products protect plants from cold weather and high winds, allowing growers to cultivate earlier and later in the year than would normally be possible.

The earliest and most cost-effective approach to extending the growing season is to locate and take advantage of microclimates such as areas that warm up faster or retain heat longer. Orientation to the sun, wind breaks, and walls made out of materials – bricks, mortar, stone – that will hold the heat and can even prevent freeze-thaw cycles all play a part in evaluating microclimates.

Dark rocks can moderate temperature in a very small area by soaking up the heat of the day then releasing it slowly as the evening temperature cools.

Dark walls and soil will absorb and hold more heat than their light-colored counterparts. Or use plastic mulch which will shade weeds, prevent moisture loss, and raise the temperature of the soil by 5-15F on a sunny day. As plants grow, the leaves will shade plastic and stop the warming effects.

A lake, pond, or small creek will also moderate air temperature, keeping it warmer in winter and cooler in the summer.

Cloches are individual protective coverings that keep plants warm at night. A simple cloche is a milk container with the bottom cut off and the lid removed. Placed over a plant, the plastic will capture and retain heat while allowing ventilation thru the open top. You can make cloches out of wax paper, glass, or jars, or buy them. Commercial units are made of rigid transparent plastic or heavy duty wax paper. They are easy to use and stack well for storage.

The Wall O’ Water is a plant lifesaver. It is a water-filled teepee which uses the heat-emitting properties of water t shield plants from excess heat and keep them warm in the cold. It hold three gallons of water and fits over the plant. During the day, the water absorbs the heat of the sun, moderating the temperature in side the teepee. At night, as the air temperature drops, the water releases its heat, keeping the plant comfortable. The Wall O’ Water does its best work in the spring when there is still a chance of freezing. As water freezes, it releases more heat into the teepee and can protect plants down to 20F.

Covers protect early plants and can help produce a spring crop. The most uncomplicated cover is a sheet or blanket spread over the pant and held down with stones or soil. A low wattage electric light bulb carefully placed under the cover will raise the temperature 10-15F above that f the rest of the garden. Be very careful that the light bulb does not touch any part of the cover, or it may start a fire. Products such as Agronet and Reemay are spun-fiber with sun protection properties that can be used as covers in place of the sheet or blanket.

Row tunnels can be made of clear corrugated fiberglass that is bent into an arch and secured over the garden. Commercial row covers come in many sizes from large enough for dwarf fruit trees to smaller units for pepper plants and rose bushes. Those made with polypropylene will protect plants down to 35F.

Marijuana Horticulture

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