Question:
We have an oak tree (about 4′) that is growing from a seed transplant. It has had a tremendous growth spurt this spring, adding at least half its height. A powdery substance started first on the new growth at the top of the tree, but is gradually spreading to older leaves. It is causing deformity of the leaves. What do you recommend?
Answer:
This sounds like powdery mildew. It is not life threatening but if you want to control it get any fungicide that is labeled for powdery mildew and spray the plant with it. Go to your favorite nursery and ask their assistance in selecting one.

Question:
I have about 50-60 giant liriope. The majority of them have leaves turning gold, then brown. These leaves fall off the plant. I Googled it and found out that this liriope rot. Are you familiar with this rot, and if so, how does one solve this?
Answer:
There will normally be some dying leaves on all perennial plants. Giant liriope is no exception. Unless the entire plant is turning yellow (and brown) I would not worry about it. Liriope looks best when cut to the ground in early spring and before new growth commences each year.

Question:
At our farm, we planted Celebrity tomatoes and 444. The tomatoes are mottled with yellow spots. When I cut into the tomato there is white mottling inside. What is my problem? Also, they are not as sweet as I would haves expected.
Answer:
Your tomatoes have been attacked by squash bugs and/or leaf-footed bugs. These are bugs which have shield shaped bodies and feed on the tomato fruit. They are sucking insects which stick their ‘sucker’ into the fruit and feed. This makes the yellow spots and the white spots in the flesh. They are difficult to control. The application of one of the vegetable insecticide dusts will help and spraying with liquid Sevin also helps. The taste is likely due to the bugs somewhat, but also, the weather we have had, has not been ideal for tomato growth.

Question:
I’m originally from Wisconsin and miss all the Hydrangea trees and bushes. Are there any that will grow in the Texas (San Antonio) climate?
Answer:
There are none that will prosper and be long lived here because of our alkaline soil and water as well as the intense summer heat.

Question:
What type of annual flowers can I plant during the month of August in San Antonio, TX?
Answer:
You can plant periwinkles (Cora vinca), moss rose, purslane, cosmos, and zinnia to name a few.

Question:
We have what looks like black soot on the leaves of our tree. What causes this and how can we correct it. It makes a mess when rain blows through the tree on to the car port. Most of the older leaves are almost covered with this substance; it rubs off easily but an impossible task to clean each leaf. Thank you for your assistance.
Answer:
Your tree is infested with a sap sucking insect such as aphids, leaf hoppers, mealy bugs or scale. They suck the sap and excrete a sugary substance commonly called ‘honeydew’. It drops down onto the upper surface of the leaves where it attracts the sooty mold. If you get rid of the insects, you will get rid of the problem. The sooty mold will remain on the leaves until it wears off or the tree replaces those leaves. Identify which insect(s) you have then go to your favorite nursery for an insecticide that they can recommend.

Question:
How do I know when to water an aloe vera plant? I think they already have a lot of moisture, and need bright light. Is this correct?
Answer:
The aloe only need sufficient moisture to keep its leaves turgid. Fortunately, it is very difficult to kill one for lack of moisture. If the leaves start to shrivel, water it.