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

signals to produce a radicle. The radicle emerges upward to bring a new plant into the world. Once a seed is moist, it must receive a constant flow of moisture to carry nutrients, hormones, and water so that it can carry on life processes. If germinated seeds are allowed to suffer moisture stress now seedling growth will be stunted.
Temperature
    Cannabis seeds grow best at 78°F (25°C).
    Low temperatures delay germination.
    High temperatures upset seed chemistry causing poor germination.
    Seeds germinate best under the native conditions where they were grown.
    Once germinated, move seedlings to a slightly cooler growing area, and increase light levels. Avoid high temperatures and low light levels, which cause lanky growth.
Air (oxygen)
    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 deep layers of soil when sprouting. Sew seeds twice as deep as the width of the seed. A 0.125-inch (3 mm) seed should be planted 0.25-inch (6 mm) 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 choose 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 board. Put the seeds in the matchbox and shake for about 30 seconds. Remove the seeds, and make sure they have been scuffed a bit. Just a little scuffing will allow water to enter and set germination in motion.
Two Popular Germination Techniques:
One: Pre-soaking in water
    Soak seeds overnight in a glass of water. Make sure seeds get good and wet so growth is activated. Do not let seeds soak more than 24 hours, or they might get too wet, suffer oxygen deprivation, and rot. Once soaked, seeds are ready to be placed between moist paper towels to sprout or be planted in a root cube or fine, light soilless mix.
    In a warm location (70-90°F, [21-32°C]), place seeds in a moist paper towel or cheesecloth, making sure they are in darkness. Set the moist cloth or paper towel in a vertical position (so tap root grows down) on a grate (for drainage) on a dinner plate.
    Water the cloth daily, and keep it moist. Let excess water drain away freely. The cloth will retain enough moisture to germinate the seed in a few days. The seed contains an adequate food supply for germination. Prevent fungal attacks by watering with a mild two-percent bleach or fungicide solution. Once seeds have sprouted and the white sprout is visible, carefully pick up the fragile sprouts (with tweezers) and plant them. Take care not to expose the tender rootlet to prolonged intense light or air. Cover the germinated seed with 0.25-0.5-inch (1-2 cm) of fine planting medium with the white root tip pointing down.

To scarify seeds, place a small emery board inside a matchbox along with seeds.

Close the match box with the seeds and emery board inside.

Shake the box for about 30 seconds to rough up and scuff the seeds, so water can penetrate the outer shell.

Soak seeds in water overnight to germinate before planting.

Place seeds between leaves of a paper towel on a plate to germinate.

Add water to moisten the paper towel. Tip plate to drain off excess moisture.

Jiffy pellets expand when water is added. They make excellent pop-up pots to grow seedlings. They are also very easy to transplant
Two: Direct seed
    One of the problems with rockwool can be that the seeds heave out before germinating. This is why it is best to germinate seeds before putting them into the rockwool substrate.
    Once seeds have sprouted and the white sprout is visible, carefully pick up the fragile sprouts (with tweezers) and plant them in a pre-drilled hole in the rockwool with the white root tip pointing down. Take care not to expose