Spotted/yellowed leaves

Asked July 16, 2019, 1:52 PM EDT

Every year about this time, the leaves of my potted tomatoes and hanging basket fuchsia start out nice and green, but then they turn yellow and spotted. Here are a few photos.

Macomb County Michigan

1 Response

The tomato leaf symptoms potentially look like bacterial canker to me. A sample would need to be sent to MSU Plant and Pest Diagnostic Services to determine this for sure. If you are ever interested in that, contact them about sending in a good sample. In the meantime, here are a few resources:

Tomato Disease Identification Key by Affected Plant Part: Leaf Symptoms from Cornell University Vegetable MD Online

Bacterial Canker of Tomato from University of Kentucky Extension

The following article has a lot of good pictures. What I don’t like about it is that is mentions using fungicides to manage bacterial diseases. To me, this is misleading. A straight fungicide (something that only kills or inhibits fungal growth) would not manage bacteria, but they talk about using copper as an active ingredient, which happens to be both a fungicide and bactericide.

Bacterial canker of Tomato from a Cornell University blog

Basically, I would try to make sure your tomatoes are in full sun, have good large pots and consistent watering, so the soil stays moist, but not soaking wet. If possible, I would also water in the morning at the base of the plant and avoid wetting the leaves and upper part of the plant. Also avoid working with the plant when wet.

In the coming years, if you aren’t doing this already, I would put fresh potting media in your pots and clean and sanitize your pots before putting in the fresh potting media. First clean off the pots and remove as much debris as possible then one way to sanitize the pots is by soaking them with a 10% bleach solution (of course being careful of the bleach). Ideally materials would be soaked for 30 minutes to kill the pathogens, though I realize that might be more difficult for large pots. It’s a good idea to sanitize all garden tools and containers, especially if they’re been in contact with potentially diseased plants. Again, clean things off and remove debris first. Note that bleach can be corrosive to metal tools like pruners. Isopropyl alcohol can also be used for sanitation, and the materials can just be sprayed (they don’t have to soak).

Also look for disease-resistant plant varieties and check your transplants for potential disease before bringing them home.

I’m not sure about the Fuchsia. I looked into some different insect and disease pests it might have but did not find something that convinced me it was definitely what you have.

From what I’ve read it sounds like it would be best to keep it in partial shade (unlike the tomato). It seems that while there are some more heat-tolerant varieties, overall Fuchsia plants like weather milder than the hot temperatures we’ve been having in July. Consistent watering and watering in the morning may also be helpful here. You don’t want plants to be water-stressed, but prolonged leaf wetness gives diseases more of a chance to develop.

Some articles:

Annual: Fuchsia: Fuchsia x hybrida from University of Illinois Extension

Fuchsias Then and Now from PennState Extension

Fuchsia from Clemson Cooperative Extension – but when they talk about outdoor timing remember that Clemson is in South Carolina

Please let me know if you have further questions.