Jalapeno Hot pepper plant disease diagnosis



I am growing Jalapeno hot pepper plants indoors on the ledge of an east facing window with grow lights overhead in potting soil.

The grow lights are run when the window isn’t in sunlight – 1pm to 9pm. I use 5-10-10 fertilizer occasionally.

I’m trying to figure out which disease the plants have. The production is low – only 1 to 2 peppers per plant so far.

I’ve attached a file with a few images. They’re more yellow in real life and there’s some “webby stuff” on the tops of the leafs. Don’t see any insects.

I removed the worst leaves and treated twice so far with safer’s 3 in 1 garden spray which includes insecticidal soap and sulfur based fungicide.

It doesn’t seem to work very well.

Do you know what’s wrong with these plants? Any treatment suggestions.

Thanks very much.


Thank you for contacting the Toronto Master Gardeners with your inquiry.

Mature jalapeno peppers require at least 8-10 hours of direct sunlight daily. Mature plants also prefer moist well-drained soil. Excessive moisture can lead to fungal diseases on plants. If you have yellowing leaves that drop and poor growth, you’re plant probably has a fungus.

One of the more common bacterial infections that affect peppers is bacterial leaf spot caused by the bacterium Xanthomonas campestris pv. Vesicatoria.

Leaves affected by bacterial leaf spots exhibit small yellowish spots. These spots may become brown or enlarge, leading to leaf drop. This diseases is spread by plant debris in the soil and through infected seeds. Once the symptoms of bacterial leaf spot begin to appear on your pepper plants, it’s usually too late to save them. Most newer varieties of peppers have disease resistant to bacterial leaf spots. Jalafeugo, Emerald Fire, Jaloro are just some exampes of resistant varieties.