Tomato plants can be productive in Louisiana. (Photo by Dan Gill)

Tomatoes can be planted with other vegetables, such as these beans, in raised beds. (Photo by Dan Gill)

For Release On Or After 03/27/15

By Dan Gill
LSU AgCenter Horticulturist

It’s time to plant tomato transplants into the garden, especially in south Louisiana. North Louisiana gardeners may want to wait another couple of weeks to be cautious. Early planted tomatoes produce more and higher-quality tomatoes and benefit from lower pest populations.

Choose varieties with the fruit size, shape, color and flavor you want when deciding on which types to grow. Disease resistance is a real advantage in our climate. Plant growth habit is also an important characteristic to consider. Determinant or bush types stay short, while indeterminate or vine types grow tall.

Although it is fun to try different varieties, the bulk of your tomato planting should be varieties that have been evaluated and recommended by the LSU AgCenter. Here are some varieties in various categories for you to consider:

–Indeterminate (vining): Better Boy, Big Beef, Champion, Jet Star, Pink Girl, Sun Gold, Terrific.

–Determinate (bush): Bella Rosa, BHN 981 and BHN 876, Carolina Gold, Celebrity, Crista, Floralina, Mountain Fresh Plus, Mountain Spring.

–Heat-tolerant (suitable for planting as late as May for summer production): Florida 91, Heatwave II, Phoenix, Solar Set, Sun Leaper, Sun Master, Solar Fire, Talladega.

–Small-fruited: Cupid, Juliet (AAS), Small Fry (AAS), Sweet Million, Sun Gold Cherry.

–Paste tomatoes: Muriel Roma, Picus Roma.

Start off with high-quality transplants. The ideal transplant is a stocky plant – about as wide as it is tall – that is growing actively and has not begun to bloom. The leaves should be deep green, and the stem should be thick enough to support the plant strongly. The roots should be white, and some soil should still be visible between roots when you remove the plant from the pot.

Avoid purchasing transplants that have been crowded together to save space, causing the stems to stretch and become weak, or those that have been grown too long in pots that are too small, making them severely potbound.

Newly purchased transplants are often right out of the greenhouse and may not be ready for the harsher growing conditions of the real-world garden. Harden off the transplants by placing them in a location that receives several hours of morning sun for a couple of days, and gradually introduce them to more sun over a seven-day period. Also, allow the plants to wilt very slightly before watering.

Select a spot to plant your tomato plants that receives full sun – direct sun for eight hours or more. Production will be lower with less light. Tomato plants prefer a fertile, well-drained soil that has high organic matter content. During bed preparation, dig in generous amounts of compost or rotted manure and some general purpose granular fertilizer or organic fertilizer following label directions. Don’t overdo the fertilizer at first – you can always apply more later on.

Plant tomatoes on raised rows in the garden or in raised beds. Tomatoes grow best when spaced at least 18 to 24 inches apart. A common mistake is to plant the small transplants too close together.

You may plant transplants 1 or 2 inches deeper than they were growing in their containers. Do not remove healthy, green leaves to bury the stem deeper because this may actually stunt the plant.

If you purchase a lower-quality transplant that has stretched toward light and has a long stem, you may bury a significant part of the stem underground. Dig a trench about 2 inches deep and about half as long as height of the transplant. Lay the root ball and the lower stem down in the trench, gently bend the upper end of the transplant upright, and cover the root ball and lower stem with soil.

Each tomato transplant should receive about 1 cup of soluble fertilizer or fish emulsion at planting to get it off to a good start. Water regularly until the root system is well-established. And don’t forget to keep your plants mulched with 2 to 3 inches of leaves, pine straw or other materials over the growing season.

Tomatoes are generally trained to grow upright by tying them to stakes using soft fabric. This saves space in the garden and keeps the fruit off of the ground, reducing problems with fruit rot.

Indeterminate types are pruned primarily to make them more manageable to train on stakes, but it also encourages plants to produce larger, higher-quality fruit. Prune your plants to one or two main stems by pinching off the suckers (or side shoots) that grow where a leaf attaches to the main stem. To train a plant to two main stems, allow the first strong sucker to grow, then desucker both main stems as they continue to grow.

Determinate tomatoes may be grown on stakes or in commercial tomato cages and are not desuckered in either case.

After the first tomatoes have reached the size of a quarter, sidedress your plants by sprinkling about one tablespoon of general-purpose granular fertilizer or blood meal under each plant to keep them growing vigorously, and repeat every four weeks.

Be sure to plant earlier rather than later for best results. Tomato planting should finish up by mid- to late April unless you plant the heat-tolerant varieties.

Boy, I can almost taste those vine-ripened tomatoes now.

Rick Bogren