Tomatoes are not a low maintenance vegetable. If you want a plentiful and attractive and tasty crop you will need to pay attention to the plant's needs all through the season.
Organic mulches that cover bare soil over plant roots slowly feed the beneficial soil microbes, discourage weeds and help retain soil moisture. They also influence soil temperature by cooling it in the heat of summer to promote tomato plant health. Tomatoes don't like it much when the soil temperature exceeds 85 degrees. That 3 to 4 inches of organic mulch will cool the soil 5 degrees or more in the summer and prevent it from drying out.
What About Plastic Mulches?
Some books recommend using black plastic mulch for giving tomatoes a good start in the early spring. You will also see ads for red plastic mulches which in the commercial sector have proven to help with an earlier and bigger harvest of tomatoes. For the beginning veggie grower we recommend sticking with the organic mulch primarily because it is food for those very important beneficial soil microbes. The plastic mulch heats the soil and keeps down weeds, but is not only not food for those microbes, it serves as a barrier to organic matter.
For complete details see our file Mulching The Vegetable Garden
Tomatoes are picky about water. Too much water rots roots; too little stops fruit production. Consistency is the cry. Try to provide fairly even moisture, rather than allowing the soil to be very dry, then very wet and then very dry again. This stresses the plants, inviting disease and makes them mad.
Tomatoes like a continuous and uniform water supply, but not soggy soil. They need about an inch of water a week from you and the rain in spring and fall, and two inches a week when the summer gets very hot in July and August.
Ideally, water early in the day, soaking the soil, not the leaves. A watering wand works very well in this job. If you can’t get to it till evening go ahead anyway. Let the water trickle slowly so it penetrates the soil to 8 to 10 inches. During periods of sparse rainfall check soil moisture every 3 or 4 days, more often in windy areas and during the hot summer. A layer of mulch will help retain soil moisture. Porous soaker hose systems hooked up to a mechanical or computerized timer are very effective for delivering water properly to the entire vegetable patch.
For more details see our file Watering the Vegetable Garden
To boost the harvest feed tomato plants lightly every month during the growing season. Either sprinkle about a tablespoon of organic granular fertilizer around the base of each plant away from the stem for the rain to soak in or spray plant foliage with liquid organic fertilizer containing kelp diluted according to label instructions.
Pruning or Grooming Tomatoes
If you want to start an argument or at least have a really heated discussion, get two or three tomato gardeners in the same room and try to get agreement about pruning tomatoes. There almost as many opinions as there are tomato gardeners. So consider this task as definitely optional. If you do not prune your tomatoes at all, you will get lots of tomatoes. Those that believe in pruning feel they get bigger and tastier tomatoes.
Only indeterminate types of tomatoes might be pruned if that is your preference. Train the plants to single strong stems by pinching off tiny, young secondary stems, or “suckers,” which develop where leafstalks join the main stem. Pinch them with your fingers rather than use a knife or pruners to minimize the risk of spreading disease. Reducing the number of suckers yields fewer, but larger tomatoes and controls the spread of each plant. Also, remove the bottom branches and leaf stems from staked or caged tomato plants to foster better air circulation. Those branches don’t bear fruit.
An optional measure is to pinch the tops of indeterminate plants to remove their growing tips when they reach the top of their stake or trellis. This encourages larger fruits. Do this about a month before expected first frost in the fall so fruit that is already set will have time to grow and ripen fully.