How to Grow Bountiful Tomatoes

As you move tomato plants into your garden, here’s some advice to help improve your harvest.
    First, limit the amount of fertilizer and compost you apply when you transplant your tomato plants. Applying too much high-nitrogen fertilizer or high-nitrogen compost will produce extra-large plants and few late tomatoes.
    It’s in the production cycle that tomatoes need nitrogen.
    A fruiting plant must absorb nutrients sufficient not only to produce fruit but also to continue growing, producing more foliage, flowers and fruit. In other words, a mature tomato plant is much like a pregnant woman, eating for two to remain healthy and produce healthy offspring.
    That’s when the tomato plant is most nutritional needy, too. And that’s when early blight strikes.
    For a decade I have been studying methods of preventing early blight. Since 2009, I have had no early blight symptoms. I attribute that success to keeping my tomato plants nutritionally happy. Nitrogen is the key to a plant’s nutritional health.
    Nitrogen passes to upper-growing points or fruit from older leaves. Losing nitrogen makes those leaves susceptible to blight-causing microorganisms. If you supply tomato plants with sufficient nitrogen for the bottom leaves to remain strong and healthy, they are less likely to succumb to infection.
    Thus for the past five years, I’ve scattered a rounded tablespoon of calcium nitrate 15.5-0-0 around the base of each plant as soon as I see the first cluster of tomatoes form. During the growing season, I watch the bottom leaves of the plants closely. When those leaves start to turn yellow-green, I make a repeat application of calcium nitrate. Generally only two applications are needed per growing season.
    I selected calcium nitrate because mature plants absorb nitrate nitrogen more efficiently than they do other sources of nitrogen. Plus, the calcium in calcium nitrate helps build stronger cell walls and prevent blossom-end rot. There is lime in the soil, but the calcium in lime is only four percent soluble while the calcium in calcium nitrate is 100 percent available. Calcium is as important in plants for making strong cell walls as it is in humans and animals in making strong bones and teeth.
    If you are an organic gardener, apply at least two inches of compost around tomato plants as soon as you see the first flowers. Lobster waste or crab waste compost has the highest levels of calcium of all composted products available. Irrigate through the compost.


Ask Dr. Gouin your questions at [email protected]. Please include your name and address.