What’s Wrong With My Tomato Plants?

Caring for your Tomatoes.

You’ve carefully brought your plants home from The Greenhouse, you’ve waited till there’s no chance of a frost and lovingly planted them outside in the warm soil. The companion plants in your vegetable patch are perfectly chosen;
borage, chive, nasturtium, basil, carrot, sage, onion, garlic, lettuce, asparagus, bean, cucumber, mint and parsley are thriving. Water has been generously applied and the liquid fertilizer has flowed in just the right amount.

But! Your tomatoes are not happy.

Unfortunately tomato plants can suffer from a multitude of things, aphids, flea beetles, tomato hornworm, whiteflies, blossom-end rot, late blight, mosaic virus, cracking…to name but a few of the most common. The critters are dealt with in The Greenhouse’s other post: “Insects: The Good The Bad and The Ugly” so we’ll just talk about the other problems.

Lets start with a quick word about: Prevention.

  • Because tomatoes are so disease prone, it is important to water from the ground and avoid sprinkling the leaves. Soaker hoses are most effective as they will not splash dirt onto the stems of the tomatoes. By keeping their stems clean, you are lessening their chance at picking up diseases.
  • You’ll need to stake or cage your tomatoes. This will help support them and keep the fruit and stems off of the ground.
  • Mulch. It’ll help with moisture control and keep those stems clean.


Blossom End Rot
Basically, what happens is the fruit turns back on the bottom. It begins to rot from the bottom up. It is very difficult to save any fruit that has this on it. Caused by lack of calcium usually DUE TO IMPROPER WATERING. The best way to fix this problem is regular watering so the plant can uptake nitrogen through the ground water. Also consider sure you fertilizer about once a month.



Image result for tobacco mosaic virus tomatoTobacco Mosaic Virus
You know you have this when your tomatoes become yellow and green spotted. They may even develop brown patches on them as well. If you are a smoker, be sure to wash your hands thoroughly before touching your tomato plants.
Also, be sure not to plant where any infected tomato or tobacco plants were planted previously. If you find it hard to eradicate, look for resistant varieties.



Image result for radial cracking tomatoRadial Cracking
When the top of the tomato begins to crack and split. Majority of the tomato is still salvageable, but it is a pain nonetheless. The best thing you can do is select varieties that don’t do this. Unfortunately it’s common in most larger varieties.
You can also help prevent this by watering consistently and stopping large changes in moisture by mulching.



sour_rotSour Rot/White Mold
This is when your tomato cracks and has white, scummy fungus coming out of it. Destroy the affected fruit and improve conditions. The best thing you can do is to not wet the surface of the tomatoes when watering and be sure to stake your tomatoes properly to keep the fruit off the soil.





Image result for tomato alternaria spotAlternaria
You know you have this when your green fruit starts to have gray sunken spots on it. Be careful not to damage your plant when pruning. Also, water by ground irrigation instead of using a sprinkling method.



See the source imageAnthracnose is a fungi that causes fruit rot. There are many types of rot that can affect tomatoes, but anthracnose is especially prevalent. The fungus survives and even overwinters in old plant debris but can also be contained in seeds. Wet weather or splashing from irrigation provides ideal conditions for disease development, as do temperatures of 80 degrees Fahrenheit (27 C.) or more. Remove and destroy infected fruit. Ensure ground watering, mulching and keep fruit and leaves off the soil. Rotate crops and keep soil weed free. Use an organic fungicidal product.



This is where older leaves on the tomato plant begin to turn yellow and brown. They will eventually wilt. This happens mainly during colder weather. The only way to prevent this from happening is buying a variety of plant that is resistant to it.



Image result for early blight tomatoEarly Blight
This is when the fruit appears with dark and leathery lesions on the skin near the stem. This can be prevented with organic fungicide sprays and by rotating your crops.