Texas Tomato Lover's Handbook

6. Insects, Diseases, Weeds, and Varmints: Tomato Pests

123 I n s e c t s , D I s e A s e s , W e e D s , A n D V A R M I n t s Insects,฀ Diseases, Weeds,฀and Varmints Tomato Pests Gardeners are not the only ones who love tomatoes. Insects and critters love the tomato’s juicy sweetness, diseases thrive on the nutrient-rich plants, and weeds flourish in the high fertility of the soil where tomatoes grow. In a good year, when spring rains don’t fall too frequently and you plant early to avoid the leaf-footed bugs, you will likely harvest a good crop without any spraying. Frequent rains favor the early blight fungus, and by late July the bugs are thriving. A rainy spring almost ensures that you will need to apply a preventive fungicide for disease control. Once the disease is flourishing with lower leaves turning yellow and then brown, it’s too late to control the disease in time to salvage much of a crop. There are some low-toxicity and organic fungicides that can help to save the day. Neem oil, sulfur, and a new bacillus—Bacillus subtilis— should get the job done in all but the worst years. New gardeners and especially those determined to grow organically often suppose that growing organically means no spraying. In most cases, it just means spraying more often with less toxic materials. Of course, t e X A s t o M A t o L o V e R ’ s H A n D B o o K 124 there are other factors. If the gardener is serious about enriching the soil with compost and carefully monitoring the garden to keep ahead of pest problems, he or she may, in fact, grow a super crop of tomatoes with little or no spraying. Regardless, it pays to know what sprays are available— chemical and organic. Just remember that it’s naïve to presume that just because you use compost, the bugs and diseases will stay away. If you follow the label directions, including the days to harvest (after spraying), you don’t need to worry about the quality of tomatoes you harvest. Even with so-called chemical pesticides, the levels are so low at harvest time—assuming you use the correct rate of application and wait the required days to harvest—as to be inconsequential. Remember that it’s the dose that counts. Many of the medicines we take are toxic if taken at high rates. Knowing where to turn to deal with pests and diseases is another important factor. Master Gardening is a volunteer program of Texas A&M University’s AgriLife Extension. Master Gardeners who graduate from the program are available at many local AgriLife Extension offices to answer most of your gardening questions via the telephone, or you can usually bring samples in for analysis. These services are more extensive in the large metropolitan centers, but Master Gardeners are spread across the state. County extension agents can assist with the more difficult or commercial questions, and the Texas A&M specialty staff (entomology, pathology, and weed science) are available via the Internet. Check with your local county extension agent about how to submit samples (good digital photos are often adequate). The following Web sites will prove invaluable: http://aggie-horticulture.tamu.edu/, http://insects.tamu.edu/extension/, http://plantpathology.tamu.edu/extensionprograms/index.htm, and http://soilcrop.tamu.edu/research/weeds/index.html. 125 I n s e c t s , D I s e A s e s , W e e D s , A n D V A R M I n t s Most gardeners take a commonsense approach and use a range of pesticides and fertilizers, both organic and inorganic, with emphasis on low-toxicity materials. t e X A s t o M A t o L o V e R ’ s H A n D B o o K 126 You need a plan if you want to grow a pest-free tomato crop with a minimum number of sprays. The following list summarizes the steps in planning your garden. 1. Prepare a fertile soil bed, rich in organic matter, with a good fertility base. It’s best to fertilize based on a soil test, but 1 to 2 pounds of a complete fertilizer like 15-5-10 per 100 square feet is a good starting point if there is...