Growing Your Own Transplants

— Written By Mary Hollingsworth and last updated by

The photographs of the beautiful red tomatoes in the seed catalogs make me think about gardening.  It is too early to start seeds for transplants of warm season crops such as tomatoes and peppers, but it is time to plan and collect supplies.  Cool season vegetables such as cabbage can be started now.  Growing your own transplants requires the ability to control the temperature, light, moisture, and ventilation, which are crucial for producing quality plants.

Seeds of cool season crops such as cabbage, lettuce, and broccoli can be started five to seven weeks before transplanting to the garden.  Cabbage and lettuce seed started now can be transplanted outside about March 15.  Plant broccoli seeds two weeks later for a March 30 planting target.

Eggplant and pepper transplants are ready for the garden six to eight weeks after seeding. They can be started around March 12.  These warm-season crops do not tolerate frost. They are best transplanted into the garden the first week of May, since they are very sensitive to cool soil and air temperatures.

Tomato seeds planted around March 22 will be ready for the garden four to six weeks after seeding. Tomato plants can be transplanted into the garden starting the last week in April. Like eggplants and peppers, tomatoes are a warm-season crop.   You may need to cover them if a frost is predicted when the plants are in the garden.

Cucumber, muskmelon, squash, and watermelon can be started around April 12 and will be ready to transplant in two to three weeks. Transplant these into the garden after May 1 since they require warm temperatures to grow.

You can buy all the materials needed for starting transplants from local garden centers or through seed and garden supply catalogs. For starting eggplant, pepper, and tomato use an artificial growing medium of peat moss and perlite or a commercial seedling mix available at garden centers. Purchased artificial growing medium and commercial mixes are sterile, which means less risk of losing the seedlings to disease.

Fill a plastic tray with the moistened medium. Dry medium is difficult to moisten evenly after it is placed in the plastic tray. Sow the seeds in rows within the tray or broadcast the seeds over the growing medium. Lightly cover the seed with growing medium to moisten the soil with water. Next, place the seeded trays in a plastic bag to keep the top of the growing medium from drying out quickly. Keep trays at room temperature until the seedlings begin to emerge.  Then remove the plastic bag and transfer the trays to suitable growing areas.

While the seedlings are still small, about one to two weeks after they emerge, transplant the seedlings into 3- to 4-inch plastic pots, cell packs, Styrofoam cups, paper cups, milk cartons, or small peat pots which are filled with a commercial potting mix.  Make sure the containers have holes in the bottom for good water drainage. If the seedlings are not transplanted into individual packs or containers, the roots will be tangled together and severely damaged when transplanted into the garden.  Put individual pots or packs in plastic or metal trays for growing and for convenience when you water and handle them. Place the trays back under the lights.  Remove excess water from the trays so the seedlings will not rot.  To save time with transplanting seedlings, eggplant, pepper, and tomato seeds can be planted directly into individual containers.

Start cucumber, muskmelon, squash, and watermelon seeds in individual peat pots or peat pellets because their roots do not like to be disturbed after germination.  Roots can grow through the peat pot or pellets and the peat pot or pellets can be planted with the plant. Tear off the top edge of the peat pot when planting.  If the top of the pot is above the soil the peat pot will dry out and damage roots near the pot’s edge.

Fertilize the plants when the second true leaves appear.  Use a fertilizer such as 20-20-20 at rates recommended on the package. Fertilize again in another week or two.

One week before transplanting the plants into the garden, harden off the plants by placing them in a cool spot and reducing the amount of water; don’t allow them to dry out and wilt.  This hardening off process helps the plants to acclimate to outside conditions.

If you can’t provide good growing conditions, the quality of your homegrown plants may not be desirable.  Quality transplants are needed for quality vegetables and good yields.

If you would like to gain valuable information on how to germinate seeds contact Mary Hollingsworth, North Carolina Cooperative Extension horticulture agent,  at the Hoke County Center at 910-875-3461 or by E-mail at mary_hollingsworth@ncsu.edu.

Written By

Photo of Mary HollingsworthMary HollingsworthExtension Agent, Agriculture - Horticulture (910) 875-3461 (Office) mary_hollingsworth@ncsu.eduHoke County, North Carolina
Updated on Sep 24, 2013
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