Seed Starting Secrets

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And, as is the case with those youngsters, there are genetic secrets locked within each seed that give it its uniqueness. This carrot may have a delicate grandma several generations back that accounts for its sweetness, and that lettuce perhaps had "weedy characters" in its lineage, making its taste spunky but its hardiness commendable. Our goal, then, is to coax out of dormancy the special fruits and vegetables hidden within each seed.

A CLOSER LOOK

You may not hear sighs from your seed packets or jars over the winter, but the embryonic plants are in there "breathing" just the same; oxygen is being taken in and carbon dioxide is being released. They are alive. However, it takes different degrees of moisture, light, darkness, oxygen, and temperature to bring each type of seed to germination, and therein lies more magic. The seed coat softens, water is imbibed, enzymes are activated, and the easily stored starches and proteins are converted into the simple foods of glucose, maltose, amides, and free amino acids needed by the emerging plant. First to burgeon is the primary root, "dowsing" ever downward. The stem (hypocotyl) follows, breaking ground and surfacing with the mission of carrying the first true leaves into the sunlight where they can begin to photosynthesize. Eventually the plant matures and makes seed of its own, and the cycle begins again.

Remember in grade school when you grew bean seeds in cutoff milk cartons? If you soaked them first, your teacher may have pulled a swollen seed apart and showed you the first true infantile leaves, the protruding tap root (or radical), and the cotyledons, or seed leaves, that would provide the nourishment for early growth. Beans, like the majority of garden vegetables, are dicots. That means that they have two cotyledons. Corn, grasses, and onions are called monocots, and have one cotyledon along with endosperm to provide "breakfast" for the seedling. In either case, the guardian of all this inner life is the seed coat. It regulates the intake of water, oxygen, and light by the seed and holds things in check until the right conditions are present for growth. In many seeds, the latter task is handled by chemicals that inhibit germination. This can seem counter-productive to a gardener's wishes at times, to be sure, but it keeps seeds from jumping the gun and being fooled by a little warmth or moisture before the timing is right. So how, then, can we best control all of these factors in order to get seeds off to an early, and healthy, start?

CRITICAL CONSIDERATIONS AND POTENTIAL PROBLEMS

Moisture must be removed in order for seeds to be stored for any length of time; by the same token, it must be added if germination is to take place. Now the swelling of a seed with water (imbibition) isn't an accurate sign of viability. As is the case with a sponge, this can be a purely physical reaction. But when a living seed drinks in water, the seed coat softens, allowing the root to emerge. Respiration speeds up, the embryo starts to grow, and enzymes are activated to break down nutrients and make them available.

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