Air (Oxygen)

Marijuana Horticulture

by Jorge Cervantes

Seeds need air to germinate. Moist, soggy growing mediums will cut off oxygen supplies and the seed will literally drown. Seeds germinate poorly when planted too deeply. Tender seedlings do not have sufficient stored energy to drive through layers of soil when sprouting. Sew seeds twice as deep as the width of the seed. A 0.125-inch (3mm) seed should be planted 0.25-inch (6mm) deep.

Household water contains enough dissolved solids (food) to nourish seeds through their first few weeks of life. Although seeds need only 30-50 ppm of nitrates before they germinate, any more will disrupt internal chemistry. Some growers chose to use distilled water that contains practically no dissolved solids to germinate seeds. In fact, a high concentration of dissolved solids (salts) in the water will actually pull moisture out of the seed!

Start feeding two to four weeks after seedlings have sprouted. Some growers wait until leaves yellow to begin feeding. Use a mild quarter strength solution. If yellowing persists, give seedlings a little more fertilizer.

Some seeds have a very hard outer shell, testa, and must be scarified to allow water to penetrate. To scarify, line a matchbox with a piece of fine-grain sandpaper or emery bard. Put the seeds in the matchbox and shake for abut 30 seconds. Remove the seeds, and make sure they have been scuffed a bit. Just a little scuffing will allow water t enter and set germination in motion.