People love growing tomatoes in containers in their homes, and as a general rule, they are easy to grow. Just like with other fruits, tomatoes can have problems at some point either with the leaves or with the fruit itself.
One common problem is the leaves of the plant turning brown, and sometimes they wrinkle and curl up as well. If this happens to you, there’s no need to worry because there are solutions to this problem.
Top Causes of Brown leaves on tomato plants in containers
Here are the top causes of brown leaves on tomato plants in containers and how to solve each one.
1. Lack of water
If your tomato leaves look “crispy” and have brown edges, it simply means the plant isn’t getting enough water.
Tomato plants shouldn’t be soaking wet, but you also don’t want to underwater them, either. If this is the problem, the best thing you can do is learn to water the tomato plants correctly.
Water tomatoes deeply, slowly, and frequently. For the best results, water your plants in the morning while it’s a little cooler outside.
Tomato roots are deep, and the water has to get all the way down to the bottom of those roots
Shallow watering doesn’t work, so make sure the water goes as deep as the roots of the plant.
2. You Might Have Spider Mite
If you notice tiny brown spots on your tomato leaves and see some signs of webbing, you likely have spider mite.
These pests stick to the undersides of the leaves and suck the sap from them. If they do this long enough, the leaves will die.
Sometimes, they turn a reddish-brown or yellow color before they die and fall off the plant.
If you water the plants correctly, you shouldn’t have problems with mites, but if you do, use a little neem oil or insecticidal soap to get rid of them.
If you’ve tried everything and you still can’t get rid of the mites, it might be time to dig up the plants and dispose of them.
3. Your Plants Have Canker
Caused by bacteria, canker is a disease that results in leaf edges that are brown and crunchy and leaves that have huge brown spots on them, often having yellow streaks as well.
The longer your plants have this disease, the weaker the leaves will get until they finally die and fall off altogether.
You have to be careful with canker because this disease can affect the fruit as well as the leaves.
Unfortunately, canker is incurable, so you’ll need to dispose of the plants. To prevent this disease in the first place, make sure to water frequently and correctly, as well as mulch frequently.
Rotate your crops, keep your garden area clean, and buy your seeds only from a reputable source.
4. Your Plants Have Early Blight Disease
Early blight is caused by a fungus and is characterized by brown or yellow spots. As the disease progresses, the spots can become larger, and they can also affect both the leaves and the fruit itself, not to mention the stems.
With early blight, it’s much easier to prevent the disease than to fight it. The only thing you can do when you notice it attacking your tomato plants is to remove the foliage completely.
Even better, make it a habit to check your leaves daily so that you can catch the spots before they become any worse. This is the easiest way to control early blight disease.
To prevent the disease in the first place, you can choose a variety that is resistant to early blight disease, practice crop rotation and use mulch at the base of the plants.
Apply a copper-based fungicide, stake or cage your tomatoes for better air circulation, and water the plants properly.
5. Your Plants Have Late Blight Disease
While both early blight and late blight diseases are fungal in nature, late blight disease causes the plant to die much quicker.
Eventually, the entire plant will consist of tons of spots, and that’s the main characteristic of this disease. The spots start as green but darken until they become almost black. Sometimes, you get white fuzzy mold in addition to the spots.
To prevent this disease, practice the same tips mentioned above for early blight disease. Just keep in mind that late blight disease can get really bad and destroy the entire plant very quickly.
Once it does, your best bet is just to uproot and dispose of it.
6. You Might Have Bacterial Leaf Spot
Bacterial leaf spot is a bacterial disease that affects mostly the leaves of the tomato plants. Brown spots with yellow halos on the leaves are a sure sign that you have this disease.
Eventually, the plant will be inundated with lots of ringed spots that look bad and kill the plant fairly quickly.
To prevent bacterial leaf spot, start by searching for bacteria-free seeds. Always check the seeds carefully before planting them and store them properly. Proper watering also helps, and concentrate your watering at the bottom of the plant and never overhead. Clean and sterilize your tools and keep a clean garden as well.
Unfortunately, these things may not work, and if they don’t you’ll have to discard the plants immediately.
This is partly because bacterial leaf spot can spread quickly and even affect—and kill—many other plants in your garden.
Brown leaves on your tomato plants are usually caused by one of several types of infections, usually either bacterial or fungal in nature. Proper watering of your tomato plants can greatly increase the odds of them remaining healthy and disease-free until they’re ready to pick and eat.
Sometimes, it’s too late for your plants, and you’ll need to dispose of them, but in the meantime, you can try one of the methods listed above, to increase your odds of success.
I am an accredited practicing dietitian, experienced gardener and a dedicated cook. I love writing and sharing my experience so you can learn from my successes and mistakes.