Question
I have recently planted (a few weeks ago) a small 1 foot tomato plant. I put it in good soil and have spaced it well with other herbs for my herb garden. I also water it frequently.

I have recently noticed that the plant is beginning to get white spots on the leaves all over the shrub. Also, the bottom leaves are turning a lime green while the top leaves are still the rich green color. In addition, the bottom leaves are beginning to get holes in them with a diseased appearance.

The surrounding herbs appear fine. This is my first attempt at gardening although I would consider myself a possessor of a green thumb, at least. I do not know what could be causing the blight. My guess could be over-watering or some sort of pest infestation? Since I noticed the white spots I have stopped watering the plant.

What should I do?

Thanks.

Answer
Watering in the evening can cause various fungus diseases, including blight and powdery mildew. This is due to the water staying on the plant rather than evaporating from the sun. You also need to spray the plants with a copper-based fungicide to help control the disease from spreading.

In the future, be sure to water in the morning, and only a couple of times per week. Always water deeply, so that the water penetrates well into the soil. This will cause the roots to reach straight down rather than to the surface, which weakens the plant. You also want to mulch the plants with shredded leaves, compost, or straw to help retain moisture and cool the soil.

In regard to fungicides, I personally use a product called Soap Shield from a web company named Gardens Alive. Your local garden center will also carry products to combat these conditions.

Finally, attempt to grow hybrids that have been bred to resist disease. Many of the older heirlooms are extremely susceptible, especially in wet, humid conditions.

I hope this answered your question. Please write again if I can ever provide assistance.

Regards,

Mike