Question: I have a friend who would like to know the best time to prune his crape myrtles. I told him about February. Is this correct?
Answer: Pruning crape myrtles is always a hot topic. Some gardeners like to do very limited pruning, while others do very little at all. This is the story. Crape myrtles don’t seem to care about how you prune them. Some gardeners cut back to the same spot each year, while others remove old seed heads and shorten the stem length somewhat. Many gardeners simply remove suckers from the base of shrubs and tree forms and remove tangled branches and branches that can affect movement around the plant. And here’s the good news. Crape myrtle usually resumes growth in the spring and produces many flowers. After heavy pruning, flowers are more concentrated in clusters on branches. Light pruning will distribute the flowers more openly throughout the plant. Mid-to-late January or February is usually the time to do any necessary pruning.
Q: My crape myrtles are growing in a nearby oak tree that provides shade and fewer flowers. Will it produce more flowers if I cut it back?
A: Unfortunately, the crape myrtles are now covered in shade, so they probably won’t become good flowering shrubs again. These are sun-loving plants that gradually decline in shade. In most cases, you will need to replace the branches when they become loose and no longer produce flowers.
Q: Some of my dwarf yaupon holly is turning brown. What is killing them?
A: There is a fungus lurking inside the holly. Compact, frequently pruned dwarf yaupon hollies commonly have one of several fungal organisms. The fungus invades the stem and causes parts of the plant to decline. Try pruning dead areas back to green stems and spraying the plant with a systemic fungicide according to label directions. Giving these shrubs a more open growth habit with less pruning can reduce fungal activity. During dry periods, reduce watering to only when necessary, and during rainy seasons, do not water at all.
Q: My large hibiscus shrub was damaged by roof cleaning chemicals. I washed it off with a hose, but all the leaves died. I watered it abundantly. Is there anything else I can do?
Botany Doctor: What does bougainvillea need to bloom well?
A: Losing your plants is unfortunate, but this can happen when bleach or similar cleaning products come into contact with your plants. You have done everything you can to save Hibiscus. Refrain from watering until the soil is dry. Further heavy watering can lead to root rot and further plant decline. Hopefully the chemicals will bind or break down in the soil. Scratch the hibiscus stem regularly to see if it remains green and alive. It may take several weeks for new buds to form and open.
Q: Should I be concerned about flat gray growths forming on the branches of my grapefruit tree? Does it look like lichen?
A: We were able to successfully diagnose this concern. This is a lichen that grows on the surface of grapefruit bark. It is very flat and has a bluish-gray color. Lichens do not harm plants and are a combination of fungi and algae that grow symbiotically. If you have problems with other plants, lichens can grow very aggressively, but this is not the case with your tree. There is no need to worry or seek treatment.
Q: I’m getting restless about heavily pruning my approximately 10-foot-tall Florida anise and currently blooming red cordyline. I want to cut each half in half. Is now a good time?
A: Could you please take some time to do some research in a good gardening book, plant some transplant seeds, or pull some weeds? The best time to prune is about a month away. is. Anise probably won’t mind hard pruning, but perhaps Cordyline, a titanium plant, won’t be happy. Anise shrubs that can grow into a tree are hardy and will not be affected by the cold weather that may be coming. Cordyline is cold sensitive, so it is probably more likely to be damaged by winter weather. We recommend delaying pruning this shrubby perennial until early or mid-March.
January in Central Florida Gardens
McCubbin offers advice on Florida gardening, including caring for crape myrtles, dwarf yaupon holly, hibiscus, lichens, anise, cordyline, tomatoes and aglaonemas. Maccubbin includes crape myrtle, dwarf yaupon holly, hibiscus, lichen, anise, cordyline, tomato, and aglaonema.
Q: Hurricane Milton slowed the growth of my tomatoes, but they are finally starting to ripen. When it turns red, insects dig holes in the sides. How can I harvest delicious tomatoes?
A: That caterpillar is here again. Just because it’s winter doesn’t mean you can’t enjoy these ready-to-eat fruits either. Another option is to stare at the critters and remove them from the plant, but that is not easy as many critters are fused into parts of the plant. Perhaps a more practical method is to use products containing Toricide or Spinosad, which are less toxic natural caterpillar killers. Both can be purchased at independent garden centers. Control caterpillars according to the label of your chosen product and start harvesting intact fruit.
Q: The leaves of the Aglaonema plant I am growing on my patio suddenly turned yellow. Can you see what happened?
A: Aglaonemas, often sold as varieties such as Silver Queen, Maria, and Emerald Beauty, dislike cold weather. When temperatures drop below 50 degrees, you can expect yellow leaves to appear. Remove damaged leaves and bring indoors during the cooler months. Plants need warm weather to regrow new green leaves.
Tom McCubbin is an emeritus urban horticulturist for the University of Florida Cooperative Extension Service. Write to Orlando Sentinel, PO Box 2833, Orlando, FL. 32802. Email: TomMac1996@aol.com.
First published: January 18, 2025 at 5:00 AM EST