Help for dying leaves on tomato plants
QUESTION: My tomatoes have taken on a strong blight all of a sudden. Do you think a dose of tomato fertilizer would help that? Or a fungicide treatment? Or both? The tomatoes had been extremely healthy up until a couple of weeks ago. They are producing beautiful fruit, but the leaves are starting to turn yellow, shriveling up and dying.
ANSWER: If the dying leaves are starting at the base of the plant and have black or brown spots, this could be early or late blight. These are fungal diseases that can usually be stopped from spreading with a fungicide. However, if there are no spots, this could just be the plant rejecting the lower leaves that it no longer needs. By midsummer, plants that are continuing to grow will often kick off excess leaves that they can’t take up enough moisture to support.
QUESTION: I ordered a red
maple tree from the Arbor Foundation and had it planted in my front yard in December 2015. Its branches have grown to what I feel is a length that is too long. I know nothing about proper tree maintenance. I am wondering if any of the branches should be pruned? Also, many of the leaves have black spots. Are these things to be worried about?
ANSWER: Those spots are symptoms of a leaf fungus, probably stimulated by the extremely wet weather in May and June. They are mainly cosmetic and should not do serious harm to the tree. A fungicide might stop it from spreading but won’t cure the leaves that are already infected.
As for the long branches, next winter, after the leaves have dropped, you could head back each branch by 10 to 12 inches by cutting that much off each long branch. That will force more lateral branches to develop, thickening up the canopy and making the limbs stronger, rather than longer.
QUESTION: I have 20-year-old red tips that are about 20 feet tall. They now have the canopy of a huge beech tree overpowering them. They get little sunlight because that side of the house stays in the shade from my neighbor’s tall trees. Is it possible to cut the red tips back to 5 to 6 feet and have them survive? Or should I just cut them down entirely? There are leaves at the top, but they are very spindly and have dead lower limbs.
ANSWER: You can cut them back that far, if you do it in February, before they make their new growth. However, with the overhanging trees around, it looks as if the red tips have outlived their value in your landscape. My suggestion is to get rid of them and consider replacing them with something low-growing that likes full shade. Fall is the ideal time to replace them with something better suited for that area.
QUESTION: Early in the spring, my lawn was mostly lush and green. Now it has a lot of dead grass areas that I think came from the very wet spring. Have you observed that my lawn problem is widespread in the Richmond area? What recommendations can you give me to restore my lawn?
ANSWER: Our high temperatures and high humidity have created the perfect conditions for the brown patch fungus. It shows itself as brown spots about the size of a dinner plate. Eventually, these spots can coalesce into larger irregular areas. The heavy spring rains certainly contributed as can spring nitrogen applications. The lush spring growth is the most susceptible to the disease. The good news is, although it looks bad now, it only affects the blades and not the roots. As a result, once we get into the less humid, lower temps of late summer, you will mow off the infected grass and the new sprouts will fully recover. Fungicides can be used preventatively, if started at the first signs of infection. However, fungicides don’t cure the infected areas, they only help to slow down the spread. This late in the summer, it may be best to live with it and be prepared to do some light overseeding around Labor Day.
Spots on maple leaves can be symptoms of a fungal disease.