Everyone has questions now and then with regards to gardening. It doesn’t matter if you’ve been at it for years or if you’re new to the garden scene. Gardening Know How understands the importance of arming yourself with the right tools in getting the job done so your garden will flourish – and that includes answering those lingering questions that you may have. Tomatoes are one of the most popular crops to grow in the home garden and it isn’t because they are easy to grow.
Growing tomatoes poses many problems, from cultural issues to diseases to pest infestations. Here are some brief answers to the 10 most frequently asked questions regarding tomatoes.
Blossom end rot (BER) is a common occurrence amongst not only tomatoes but peppers, squash and eggplant. The likely reason is because the plant can’t take the calcium out of the soil fast enough to keep up with growth, or stress has caused the plant to be unable to process the calcium. The key to averting BER is to keep the plant from experiencing stress. In the future, be sure to plant your tomatoes in well-draining, organic rich soil, water adequately and, if you fertilize, opt for one lower in nitrogen. As to your current batch of tomatoes, adding some crushed eggshells, limestone or calcium carbonate into the soil may or may not help, but it certainly won’t hurt.
There are numerous tomato diseases that can afflict your plant. It’s important to identify the disease in order to treat it. Tomato diseases generally fall into three categories: fungal, viral or bacterial diseases, which can only be diagnosed through lab testing. It is more important for the gardener to recognize symptoms and categories of disease to learn how to treat it. Fungal diseases may present as mold or mildew on fruit or foliage to yellowing and wilting of the plant or water soaked lesions and rotting vines. Viral diseases are often ‘mosaics,’ which result in deformed fruit, mottled foliage and general stunted growth. Bacterial diseases may also result in wilt or as fruit with raised black spots surrounded by a halo.
Container grown tomatoes require more watering and fertilizing than their brethren in the garden proper. A lack of water can cause blooms to form and then drop, thus no fruit. Tomatoes also need at least 6-8 hours of full sun. Temperature may also be an issue with fruit set. Temps that are too hot or too cool can result in a conditions called blossom drop. Weather is another factor to consider. Cold, windy or wet weather affects the bees and, without bees, there is no pollination and the plant cannot set fruit. If this is the case, you can try hand pollinating the tomato yourself. This is most often the case with potted tomato plants, especially indoors or other enclosed areas where bees are unable to get to them.
If you have some yellowing leaves on your tomato, don’t panic. It may just be the normal maturing of the plant. As the plant gets older and finishes up fruiting, lower leaves may yellow because they are not taking up enough nutrients or they aren’t getting enough sun. A lack of nitrogen in the soil may also result in yellowing. Try fertilizing with a nitrogen rich food and see if the plant doesn’t green up for you. That being said, it is also possible that foliage may be yellowing due to a fungal or bacterial disease, such as Alternaria alternata, which may require further treatment.
If you’re using a drip system, then you’re watering at the roots where it counts. A general rule of thumb for tomatoes is 2 inches of water per week for plants in the ground. Test how much water is running from the system by inserting a line into a cup of water and measuring how long it takes to fill it to 2 inches. This will give you an idea of how long to run the drip system to properly water the tomatoes. Mulching around the plants will also help to retain water. Companion planting with impatiens is ideal, as they’re great indicator plants for gauging how much water to use. The impatiens will wilt if insufficiently irrigated, thus telling you to up your tomato plant watering.
Splitting in tomatoes is called cracking and is the result of temperature and watering fluxes. Be sure to provide your plants with at least 2 inches of water per week (watering at the roots) depending upon rainfall, and mulch around the plants to retain moisture at the root zone. Splitting in fruit usually occurs after heavy amounts of rainfall following a dry spell. The tomato fruit simply cannot hold all the excess moisture, resulting in cracking to relieve the pressure. In addition to watering regularly and mulching, fertilize your tomatoes on a regular basis according to the manufacturer’s instructions. This should help keep them healthy enough to prevent cracking. Additionally, some tomato varieties are simply more prone to cracking than others. Try growing a variety resistant to fruit split whenever possible.
A likely reason for a lack of fruit is a lack of pollination. Cold, windy weather keeps the bees away, resulting in insufficient pollination. You can try your hand at hand pollinating the tomato plant or cross your fingers that the weather will return to warmer conditions and the return of the bees. If your plant has lush foliage and few, if any, blooms, the issue might simply be a result of too much nitrogen. Try adding a high phosphorus fertilizer or bone meal to the soil, which should help encourage blooming. Insufficient light or water can also affect blooming, ergo fruit set.
Each variety of tomato ripens at different times. Smaller varieties mature faster than larger fruited. Also, if you have a bumper crop of tomatoes, ripening of the fruit may take some time, as the plant needs to use lots of energy to ripen the fruit. You may just need to be patient. Otherwise, temperature may play a part in a lack of ripening. If temps are below 50 F. (10 C.) or over 85 F. (29 C.), the ripening process may grind to a halt. If the green tomatoes appear to be fully mature otherwise, you can ripen them off the vine by placing them in a paper bag, which will trap ethylene, the gas responsible for ripening.
Insect pests like your tomatoes just as much as you do. While damage can range from devastating to minimal, there are some things you can do to treat or eradicate these tomato plant pests. Floating row covers protect plants from leafhoppers, predatory mites feed on spider mites, insecticidal soap or neem oil can help with aphids and flea beetles, and caterpillars can often be eradicated with the use of Bacillus thuringiensis or garlic spray. There’s also the good old-fashioned hand picking of larger insects and worms. Pluck them from the plant and drown them in a bucket of soapy water.
Tomatoes need warm temperatures of at least 65 F. (18 C.) with 6-8 hours per day of full sun. A couple of weeks before planting, till and amend the soil with aged manure, compost or fertilizer. Harden off transplants for a week before moving them outside. After the last frost date for your area, when the soil has warmed, transplant seedlings. Plant them 2 feet apart, bury the stems and establish a cage or stakes around each plant to support it as it grows. Keep them well watered for the first few days and thereafter provide them with 2 inches of water per week. Mulch around the plants to retain moisture. Rotate the crop to prevent the transfer of disease.
Looking for additional tips on growing perfect tomatoes? Download our FREE Tomato Growing Guide and learn how to grow delicious tomatoes.
We all have questions now and then, whether long-time gardeners or those just starting out. So if you have a gardening question, get a gardening answer. We’re always here to help.