Keep your tomato plants healthy
Growing tomatoes used to be so easy. I would prepare the soil, plant the tomatoes, fertilize, water and in 70 days I would start picking ripe tomatoes — or so I thought! Why does everything have to become so complicated?
Early blight, late blight, tomato leaf spot and, of course, tomato cutworms. How do you determine what is wrong with your tomato plants?
Tomato planting season is here (once the rain stops)! Now is the time that you should have your garden soil prepared. If you tilled your soil last year, then you can rake the soil smooth and add a good quality organic garden fertilizer. If you are tilling it now, be sure to remove all plant debris from last year. But even more importantly, when purchasing tomato plants this year look for healthy plants that are blight resistant.
This year I grew my tomato plants from seed. I found a reputable nursery and chose seeds that are blight, wilt and nematode resistant. These seeds may cost a little more, but if I have a large harvest of red ripe tomatoes, it will be well worth it.
So what are these terrible diseases that are attacking our tomato plants, and what can we do to control them?
The first, and most well known, tomato villain is the tomato cutworm, Feltia Subterranea. Begin watching your plants for a brown or gray moth late in the day into evening; it will be laying the eggs that will become the tomato cutworm. Tomato cutworms can be green, pink or gray and can grow up to two inches in length. The cutworm is easy to identify because it will curl up into a tight C shape when disturbed. Regularly check your plants. Digging gently around the base of each plant will likely expose the cut worms. They are most active in the late afternoon and evening.You can protect your plants by placing a cardboard or foil collar around the plant. Place one end a few inches into the soil and the other end a few inches above. Tilling the soil in fall will destroy cutworm eggs
Tomato plants also are very susceptible to fungus, and there are a few fungi out there that love to feed on tomato plants. I will cover three of them.Tomato leaf spot is caused by the fungus Septoria Lycopersica. This fungus is most active in high humidity. Brown spots will appear on the leaves, striking older foliage first. The spots will be 1/8 inch in diameter with black specks in the center. The leaf will turn yellow and fall off. This fungus does not cause stem or fruit damage, but tomato scald may occur due to lack of protection for the fruit from the sun.The best control for this fungus is to remove infected leaves as they appear on the plant. Keep your garden tools clean to avoid infecting other plants, and water plants only in the morning to allow them to dry. A pack of Clorox wipes works well to keep your equipment clean.
Early blight, Alternaria Solani, is a fungus that is most rampant in wet conditions and on poorly nourished, stressed plants. Circular lesions will appear on leaves up to ½ inch in diameter with dark concentric circles in the center of each lesion and yellow halos around the edges. Damping off, collar rot and stem cankers will appear, and the leaves will wither, die and fall off. The fruit will also rot and fall off.The best control of this fungus is to remove and destroy infected plants at the end of the season.
Late blight, Phytophthora infestan, is a fungus that is also most rampant in wet conditions and was responsible for the potato famine of the 1940s. Pale green water-soaked spots will appear near the tips of the foliage and will turn brown to purplish black. Large brown leathery spots will appear on the fruit. Late blight does not survive over winter in the soil, but it can be present in plant debris that has not been removed and destroyed from the previous year. Any volunteer tomato plants should also be removed and destroyed. Late blight fungus can also be present on new tomato transplants or can be blown in from neighboring gardens ten miles away!Crop rotation is an effective means of control for tomato disease. It is best to plant your tomatoes in a new location every season. When planting your tomatoes, remove the first few rows of leaves from the bottom of the plant to avoid infected water from the soil splashing the plant. Allow good air circulation, water only in the morning and do not wet foliage. Healthy plants with proper nutrition are less likely to become infected. Continue to care for your plants throughout the season! Do not work in the garden when the weather is wet because you are more likely to spread the spores.I prefer to use organic and cultural means to control bugs and diseases in my garden, but sometimes it is necessary to use chemicals. If outbreaks are severe, and you do choose to use a chemical pesticide or fungicide, be sure to read instructions carefully and apply on a dry and still day. Wear the proper clothing to protect yourself from runoff or spray.While it is important to be educated about plant problems, sometimes it can seem overwhelming. The best thing you can do is to follow the above tips to avoid these diseases and keep your plants healthy. When planting your garden this year, prepare your soil properly, purchase disease resistant plants and only plant as many plants as you have the time and ability to properly care for. By planning ahead, you can make gardening less of a chore and more enjoyable.Diane Walczak is a member of the Butler County Master Gardeners
