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Ultimate Guide to Growing Tomatoes – Part 3: Tomato Plant Troubleshooting

Most tomato problems stem from poor tomato care. As we covered in part 2, if you follow a proper watering schedule, provide enough light, and give your plants the proper nutrients, you can avoid things like splitting or cracking, yellowing leaves and blossom end rot. Outside of proper plant care, there are certain steps you can take to prevent disease and pests in your tomato plants.

Common Tomato Pests

Pestrap™ Insect TrapsThe most important part of pest prevention is diligence. Watch for pests daily. Spot them before they become a problem. Look under the leaves and inside buds. Use a magnifying glass as they are often very tiny. Monitor your sticky cards. Remember, these are indicators only, they are meant to let you know of pest problems that may be present in your greenhouse or garden. They will not and are not meant to control pests.

Ladybug on Tomato PlantThe most common pests you’ll find on your tomatoes are nematodes, aphids, and the nasty tomato hornworm. If aphids appear on your tomato plants, spray them with an insecticide (there are organic insecticides out there). To prevent harmful nematodes, along with other garden pests, add marigolds to your garden. They not only deter pests, they add a nice splash of color as well. If your marigolds do not deter nematodes, unfortunately the only solution is to pull the crop and start again. For more color and to prevent aphids and whitefly, try adding nasturtiums. Ladybugs love to munch on aphids, so keeping some around your tomato plants is a natural way to control these pests. Then there are the dreaded Tomato Horn Worms. I absolutely hate Tomato Horn Worms. When you find one of these bad boys in your garden, there is no mistaking it. They are big enough to pick up and dispose of by hand, which is exactly how you get rid of them. Those ladybugs you have hanging around eating up aphids, will also eat hornworm larvae.

Tomato HornwormTo prevent an array of tomato pests, we suggest you try organic pest control. There are lots of organic products available such as Neem Oil that control a wide variety of pests. Personally, I use Azitan, Marathon II, Botanigard and Ultra-Pure Horticultural Oil.

Outside of insects, you’ll likely find some larger critters, like squirrels, rabbits, even deer, getting into your garden. The best prevention for larger pests, is a good fence and repellent.

Common Tomato Diseases

Late Tomato BlightWhen it comes to disease control with plants, an ounce of prevention is worth a pound of cure. Choose varieties that are resistant to common diseases. Keep your planting and growing area clean and free of plant debris. Plant debris left in the growing range and near the healthy plants often harbor disease and insect pests. Get debris to the compost pile ASAP. Fungal diseases are the most common problems you will have. They include early blight, late blight, and fusarium and verticillium wilt. Good air circulation helps keep fungal diseases at bay. I have used Sodium Bicarbonate, Root Shield, and Ultra-Pure Horticultural Oil in my arsenal against fungal diseases in the garden and greenhouse.

It is also vital to rotate your crops to break the disease cycle. If you planted your tomatoes in one spot last year, choose another next year. This also helps soil nutrient depletion.

Over the past three weeks we’ve covered Tomato Basics, Tomato Care, and now Tomato Troubleshooting. Seems like we’ve covered everything tomatoes, right? There’s still just a little more. The conclusion of our series, Part 4, will cover Fancy Tomatoes: A guide to heirloom and organic tomatoes. Stay tuned and happy growing (tomatoes!).

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