By Vanessa Richins
Reader Lynn S. writes:
“I have tomato plants that are getting black on the tips of their leaves. I have been spraying water on the leaves, right now I have them inside but plan on planting them today in my garden.
Are these black tips from putting too much water on them? Please help, I have never had my plants do this but I have never sprayed them with water either. Thank you for your help.”
Hi. There are at least a few possibilities for why your leaf tips are turning black.
The water on the leaves definitely could be the source of the problem. When leaves stay wet for some time, it’s an opportunity for fungal diseases to develop. It wouldn’t be quite as much as a problem if they had been outside, since the sun would dry the moisture. Since they are inside, though, the water is likely to sit on the leaf surface longer.
Water at the base, not on the leaves. In addition, try to water in the morning so there is more time for the moisture to dry if some leaves do happen to get wet.
It could also be a bacterial problem. For example, bacterial canker will turn the edges of leaves brown.
Have you been fertilizing your tomatoes? Since they are in pots, it’s very possible that too much fertilizer salts can accumulate and burn the leaves, especially if the leaves are being watered more than the soil.
Do you have many plants that are very close together? If there is not enough room for air to flow through, that could also encourage diseases.
If possible, you could send in a picture of your tomatoes so we can better see what is going on. You could also take it in to your local extension office to see if they know of problems specific to your area.
You can see if any of the pictures at the following websites match your situation:
Good luck with figuring out what is happening!