Growing Conifers From Seed

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Therefore, if you were to simply stick wild conifer seeds in the ground, it might be years before any of them began to grow. Some wouldn't sprout until bacteria and fungi had eaten away at their coatings. Others would burgeon only after exposure to fire, to repeated freezing or thawing, or in response to some other natural sequence of events. The key to success, then, is speedy germination that in some way replicates the processes found in the wild.

One easy way to achieve germination is by exposing the kernels-for periods of time that can vary from one species to another-to cold temperatures. This treatment, called "stratification," serves to break the dormancy of the embryos.

In nature, stratification occurs outdoors over the course of the winter, but it can also be brought about artificially in a refrigerator. The process is quite simple. Just soak the kernels in water for 12 to 24 hours, drain them, then layer them with slightly damp peat moss or vermiculite in ajar or plastic tub, and then refrigerate the containers for one to four months (they'll need a temperature that's below 45°F but above freezing). Some conifer seeds don't require stratification if planted fresh. However, older seeds will always benefit from exposure to a cold period, either natural or artificial.

While you can simply plant your stratified seeds in the ground outdoors, as happens in the wild, the low success rate which generally rewards that method provides a good argument for coddling your plants. To do so, you'll need wooden flats-measuring about 18 inches square and 2 to 3 inches deep-and a special bedding medium. Moist milled sphagnum moss-or equal parts of damp peat moss and vermiculite, or peat moss and perlite (all of which are available from most nurseries)-will serve the purpose. Because they're soil-free, these planting media are free of the fungi that cause "damping off'-a sudden fatal collapse of seedlings that's caused by an earthborne disease.

The seeds should be shallowly sown an inch or two apart, forming a grid pattern in the flats. The bed should be kept moist but not wet. (As an alternative, plant each of your trees-to-be in a small pot, or in a plastic foam cup with a hole in the bottom.)

After a few weeks-if you've been careful and just a little lucky-tender green needles will begin to push above the surface. Allow the shoots to straighten and begin sending out new needles, then start them on a diet of half-strength liquid organic food (try diluted fish emulsion). The new plants should be nurtured carefully and kept in a sunny, protected spot-in a greenhouse, beneath a tree, or under a fabric shade structure (which might be no more than an old piece of bed sheet stretched on a wooden frame and suspended two feet above the flats).

When the seedlings begin to crowd one another in their containers, it's time to transplant them, either to a temporary nursery bed or to large pots. (I use one-gallon metal cans, discarded by a local school cafeteria. Simply clean and punch four drainage holes in the bottom of each.) Because it's important not to disturb the plants' roots any more than necessary, I suggest carefully cutting the growing medium between the seedlings with a spatula or putty knife before lifting out the individual treelets. When you replant them, set the little evergreens in the earth to the same depth at which they were previously growing.

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