Good seedlings make a good crop


Growing your own vegetables is fun and rewarding. Some vegetables we can grow from seed, while others need a small plant or transplant to jump-start the season. Many gardeners have favorite varieties, especially of tomatoes and peppers, but not all varieties are readily available at local nurseries and garden centers. To get specific varieties, you need to grow your own transplants, and that can be easily done.

Inexpensive grow kits with clear coverings help hold in moisture and humidity until seeds germinate.

The formula for successful seedlings involves seeds, soil, water, sunlight and temperature. Seed packets contain a wealth of information. They say how deep to plant seeds and how long it takes from seeding to harvest. As a general rule, it will take a minimum of four to six weeks to grow a quality transplant, and six to eight weeks is even better. Warm-season vegetables like tomatoes, peppers and eggplant don’t go into the garden until mid-to-late April, so there is plenty of time to get started now. 

Almost all containers can be used, but it is best if they are somewhat shallow and have drainage holes, so you don’t overwater seedlings. Make sure containers are clean. You can purchase inexpensive grow kits with clear coverings to help hold in moisture and humidity until seeds germinate and have some size to them. You can use an open tray, individual cell trays or peat pellets. 

Soil and sun

Start with fresh potting soil to avoid bringing any disease into play. Don’t use garden soil, as it is too heavy

Tender plants grown indoors must gradually be exposed to outside conditions.

and can contain pathogens or weed seeds. Moisten potting soil slightly, plant seeds, and lightly water soil. Some gardeners cover the top of pots with plastic wrap to keep moisture in and humidity high. If you don’t cover soil, lightly mist it to keep it moist, but not wet. 

Many gardeners erroneously think if they have a bright, sunny window, they can grow their own seedlings. Typically, unless you have a sunroom or a greenhouse window, you don’t have enough sunlight for a long enough period to use a regular window. Resulting seedlings are usually thin and spindly — not what you are looking for. These days, artificial light sources, from LED light kits to simple shop lights, are readily available. The key is to have light sources within 4-6 inches above seedling trays and on for a minimum of 10-12 hours a day. Seedlings need at least six hours of darkness a night. Gradually raise lights as plants begin to grow, so plants don’t touch lights.

Depending on how warm or cool you keep your house, plants may benefit from a heating mat. Easily found and relatively inexpensive, heating mats act as a waterproof heating pad. Most transplants prefer air temperature between 60 and 80 degrees and soil temperatures between 50 and 85 degrees. Warm temperatures speed up growth, while cool temperatures slow things down. If it is too warm, you may get tall, spindly plants. The light source can make a difference; LED lights don’t generate any heat, while incandescent light bulbs do.

True leaves and transplants

Many gardeners tend to overseed. Once green sprouts emerge, thin out excessive amounts of plants, or

When planting transplants outdoors, try to do so early in the day.

separate them in their own small pots. Remember the first leaves to appear are seed leaves or cotyledons — not the real leaves. They won’t look anything like the second set of leaves, which are the first true leaves on the plant. Wait to transplant to larger pots until they have their true leaves. Upgrade plants slowly. If you move a tiny seedling to a large container, you will have irregular water patterns that won’t aid in root establishment. Once you upgrade the container, use a starter solution of fertilizer; any water-soluble fertilizer diluted to half strength will work fine. Don’t overdo it with fertilizer, or you can burn tender new growth. 

Begin hardening off transplants a couple of weeks before transplanting outside to the garden. Hardening off is a gradual process of taking tender plants that have been indoors and exposing them to outside conditions. Start by moving seedlings outside in a shady spot for a few hours. Each day, expose them to a bit more sunlight, moving them back inside at night. Gradually reduce watering to slow growth, but don’t allow plants to wilt. 

Then it’s time to plant. There are different planting dates for cool-season vegetables and warm-season vegetables. Many gardeners get spring fever when we have a few days of warm weather and want to start planting tomatoes, but don’t jump the gun. You don’t want to lose quality transplants to a late frost. In South Arkansas, gardeners can usually start planting warm-season crops by early April, mid-to-late April for Central Arkansas and late April to early May for the northern tier. But it isn’t a race. Better safe than sorry.

When planting transplants outdoors, try to do so early in the day, and water well after planting. Happy gardening!

Janet B. Carson is a freelance writer specializing in gardening.