Though it’s still about a month too early to plant tomato plants outdoors here in Pennsylvania, I thought I’d help you get a jump start on the season by offering some tips for planting this year’s tomato crop.
Proper planting starts with the proper timing, of course. Tomato plants don’t like cold soil or cold air temperatures. Waiting until after May 15 to do your planting is a must in our region. Keep an eye on the forecast; if May 15 arrives and the weathermen are still mentioning the threat of frost, hold off on planting your tomatoes for another week or two.
Wait ‘til it’s warm
With tomatoes, it’s always better to wait than to put them in too early. Plus, if the soil is too cold, the plants will just sit there anyway and will not grow the extensive root system they need to support plant growth and fruit production.
Once the danger of frost has completely passed, select a planting site with a minimum of 6 to 8 hours of full sun. Prepare the area by removing any existing weeds or other vegetation, and work 3 to 4 inches of organic matter (aged horse or cow manure, compost or leaf mold) into the soil.
Mature tomato plants can grow quite large, so space the plants a good 4 to 6 feet apart. To simplify the process, you may want to first arrange the still-potted transplants in the garden and move them around until you find the perfect position for each of them.
The planting process is a bit specialized for tomatoes as compared to other vegetable plants. Close examination of a tomato stem reveals thousands of small hair-like projections, each of which can develop into a root. Unlike a pepper or a cabbage, planting tomatoes deeply results in a very extensive root system which is exactly what the plant needs to better withstand drought, anchor itself and acquire nutrients.
To maximize the potential for a healthy root system, there are two effective planting methods:
1. The first tomato-planting method entails pinching off all but the topmost four leaves, digging a large, deep hole, removing the plant from its pot, gently loosening its roots (so they can more readily spread into surrounding soil), placing the plant into the hole up to the lowest leaf and filling the hole back up.
This type of deep planting results in a lush root system and well-anchored plant. Gently press the soil down to ensure good contact with the roots and stem, then water the plant in well. Since the root system on a tomato planted via this technique is so deep, the need for subsequent watering is reduced.
2. A second method, know as trench planting, also begins by removing all but the topmost four leaves. After the lower leaves are removed, dig a 3-inch-deep trench that’s nearly as long as the plant is tall. Loosen the roots with your fingers, and then lay the plant into the trench on its side, with the root system at one end of the trench and the shoot system at the other.
Carefully bend the shoot end upwards so that the lowermost leaf sits just above soil level, being cautious not to snap the stem in half. Backfill the trench and water it along the entire length of the trench.
The biggest benefit of this method is ease of digging. Though the root system will be extensive, it will also be quite shallow, increasing the importance of mulching and watering throughout the remainder of the season.
Now that your tomato crop is settled into its new home, the plants are ready to get growing. But, there are two more helpful steps to take at planting time to aid in seasonal maintenance and production.
Staking: It’s best to stake tomato transplants immediately after planting to prevent driving the stake through the plant’s spreading root system. There are many different staking systems for tomato plants, and all gardeners have their favorites. This is an essential step for reducing diseases, simplifying harvests and conserving space.
Mulching: The final tomato-planting chore is mulching. Add a 2- to 3-inch-thick layer of mulch around the base of your plants to reduce the need for supplemental water, cut down on weeds and help stabilize soil temperatures. Mulch also suppresses soil borne fungal diseases by preventing the spores from splashing up onto the leaves. Organic mulches like grass clippings from an untreated lawn, shredded leaves, straw, compost and leaf mold are terrific choices.