Starting plants for the
By Lewis Jett, WVU Extension Service Commercial Horticulture Specialist
Planting the spring vegetable garden
Most vegetables for the garden can be established from transplants as plants which are later transplanted into the spring garden. Gardeners are strongly encouraged not to be constrained by buying limited varieties of vegetables found at the local garden centers. Feel free to peruse the many vegetable seed catalogs and choose varieties with great taste, disease resistance, color, shape, or whatever intrigues your interest.
Start with good quality seed.
Gardeners should transplant as much as possible. Transplanting reduces seed costs, results in a more uniform yield and produces an earlier crop compared with direct seeding.
Vegetables such as beets, broccoli, cabbage, kale, cauliflower, kohlrabi, leeks, peas and radishes can be transplanted into the spring garden 2-3 weeks before the last spring frost date for most regions.
Using a cold frame permits earlier planting of these cool season vegetables in addition to spinach, carrots, onions, and lettuce. Warm season or tender vegetables such as tomatoes, melons and peppers should only be transplanted after the last spring frost. However, these vegetables must be seeded indoors approximately 4-6 weeks before the anticipated planting date.
Using germination mixes
A number of germination mixes can be used to start vegetable plants. The mix must be sterile and free of weed seeds and diseases.
Trays or containers for growing the plants are diverse as well. Growing trays with individual cells for each seed can be purchased at most garden stores, and germination “flats”/trays also work very well.
Peat pots/pellets and other biodegradable products can also be used. Peat pots tend to lose water more rapidly than plastic or foam transplant trays.
Flower pots, milk cartons or pie pans also make good transplant containers. If trays are being reused, make sure they have been properly washed, preferably with a 5 percent solution of bleach and water.
If using germination flats, the seed is broadcast over the media and lightly covered and watered.
After about two weeks, the seedlings are pricked out of the flats and transferred to larger growing containers.
Germination flats can be used with most warm and cool season vegetables. For other types of containers, individual seeds can be sown directly into the germination media.
Small seeds, such as lettuce, can be seeded 1/8 -1/4 inch deep. Larger seed vegetables are seeded about ¼ to ½ inch deep. Seeds should not be planted too deep. Large seeds, such as tomatoes and melons, are seeded in individual cells or containers. Seed 2-3 seeds per cell and when they emerge, thin to the most vigorous seedling.
Tomatoes, melons and peppers do very well when grown in relatively large planting containers. After the seeds have been sown, the germination mix should be thoroughly watered. Make sure the germination mix does not dry out.
Proper temperature is required for good germination. Heating or germination mats will provide bottom heat and accelerate germination. Plastic tops can be placed over the trays to trap heat. Until emergence, the trays should be placed in the warmest area available. After emergence, the seedlings can be moved to a cooler (65-70F day; 55-60°F night) environment. Bright light will accelerate even growth, so a south facing window or supplemental lights will be useful.
Supplemental lights can be used for 16 hours per day. Avoid over watering the seedlings as this will make the plants spindly and create disease problems.
A weak fertilizer solution can be used to provide nutrients to the plants each week. About 2 weeks before transplanting in the garden the transplants should be hardened off to reduce stress of transplanting. Hardening off can be accomplished by placing the young transplants in a cold frame or taken outside for a couple hours each day.