The Art of Starting Vegetable Crop From Seeds : Proper planting and storage of packets is often overlooked by gardeners.

Seeds are often taken for granted by vegetable gardeners. You buy a packet and plant the seeds--simple as that. Perhaps not; veteran gardeners realize that proper seed planting techniques play an important role in vegetable gardening and that, in addition, there is a correct way to save and store excess seeds.

Proper seed planting techniques are often overlooked in the gardener’s preoccupation with watering, fertilizing, cultivating, etc.; yet planting seeds correctly is a crucial factor in successful gardening. Here are some tips to keep in mind when sowing seeds in your garden.

The No. 1 mistake made by beginning gardeners and even some experienced ones, is planting seeds too deeply. Generally, the smaller the seed, the shallower you plant it.

The embryonic plant depends on the food stored within the seed for energy to reach the surface of the soil. When it breaks the surface, it can start manufacturing its own food through photosynthesis. If the seed is planted too deeply, its food supply runs out before it can reach the soil surface and therefore, no plant appears.

What about the seed depth recommended on the seed packets? They are all right for a light, sandy soil, but in heavier soils I would plant seeds slightly shallower than the seed packet instructions. Very tiny seeds, such as lettuce and carrots, should be just barely covered with soil.

Plant in Moist Soil

Here are some other tips that may help increase the germination rate of your seeds.

At planting time, your soil should always be loose, well-worked and enriched with organic materials. If planting in rows, scratch out a groove, place your seeds in it and cover the seeds with the loose soil. Gently tamp the soil down so that the moisture in the soil will come in contact with the seeds. Notice that I said the seeds should be covered with the soil; they should not be pushed into the soil. Seeds that have “eyes,” such as bean seeds, should be planted with the eyes down.

Always plant into a moist soil. That way you can avoid washing the seeds away by watering after you plant.

If you have a heavy soil that crusts over easily, keep the soil surface slightly moist until the seedlings appear. A good method to keep the soil from crusting is to cover the planting bed with moist burlap bags and keep the bags moist until the seedlings spear. You will need to check under the bags on a daily basis and remove them immediately when the seedlings penetrate the soil surface.

Always plant more seeds than are recommended and thin the plants to the proper spacing as per the seed packet instructions. Seeds are fairly inexpensive compared to the plants they will produce. This practice will prevent you from having bare spots in your rows due to seeds that don’t germinate.

Different Viability

Most seed packets provide gardeners with more seeds than they plant. Here are some things to keep in mind when saving excess seeds for future planting.

Several factors affect a seed’s viability. When we discuss viability, we are referring to the seed’s ability to germinate and grow into a healthy plant. Vegetable seeds differ greatly in their ability to remain viable. For instance, forget about saving onion or parsnip seeds left over from last year’s planting.

Although you will get some germination, it won’t be worthwhile. You are far better off purchasing new seeds. On the other hand, seeds from vegetables such as tomatoes and squash are well worth saving as they remain viable for five years or more if stored properly.

Two other factors affecting seed viability are moisture and temperature. For proper seed storage you need a cool, dry storage area. Even when seeds are dormant, they carry on a basic life process, but at an extremely slow rate. Moisture and warm temperature speed up this growth process and shorten the life of seeds.

Storage Places

To extend a seed’s viability, you should try to control the heat and moisture variables. The ideal place for seed storage is the refrigerator, where temperatures normally run from 34 to 45 degrees Fahrenheit. If it is not convenient to store your seeds in a refrigerator, try to locate the coolest, driest place in your home or garage.

You will be able to keep seeds drier if you store them in a moisture-proof container, such as sealed jars. I like to store my excess seeds in baby food or other small jars when I can get them. I leave seeds in their packets and then store the packet in the jars. Into each jar I also insert a tablespoon of powdered milk in a small package. The powdered milk will absorb any moisture from the interior of the jar.

Seed Storage Life

Following is a listing of various vegetable seeds and their normal storage life. Bear in mind however, that poor storage will decrease viability, while careful storage may increase it:

One year or less: Alpine strawberries, onions and parsnips. I realize that most seed charts list onion seeds as being viable for up to two years, however, I’ve found the germination rate to be very poor for most onion varieties after one year.

One to two years: chives, corn, okra and parsley. Note that some corn seed varieties remain viable up to four years.

Three years: asparagus, snap beans, carrots, leeks, lima beans, peas and spinach.

Four years: beets, broccoli, Brussels sprouts, cabbage, cauliflower, chard, melon and pepper.

Five years or more: celeriac, celery, Chinese cabbage, cucumbers, eggplant, kale, kohlrabi, lettuce, New Zealand spinach, pumpkin, radish, rutabaga, summer squash, winter squash, tomato and turnip seeds.

Keep in mind that as seeds approach the end of their viability period, you should plant more of them as the germination rate will lessen. Also note that if there is any question as to whether seeds are still viable, by all means throw them out and buy fresh seeds. After all, in relation to the crops they will produce, seeds are an inexpensive item.

Sidnam has written garden columns and features for The Times since 1975.