Here are this week’s gardening questions and answers, provided by Parker County Master Gardeners. To submit a question, send it to firstname.lastname@example.org. For more information about Parker County Master Gardeners, or to become a member, call 817-598-6096 or visit www.pcmg-texas.org.
I have beautiful caladiums; what do I do to save them for next year?
As your caladiums begin to fade in the fall carefully dig up the tubers with a shovel or garden fork, taking care not to injure them. Gently shake the soil off and stack them by variety in a cool, dry place for two weeks. You might want to put a label with the variety name on each pile. Cut the wilted leaves off just above the tuber.
Place them in ventilated cardboard boxes and cover with dry, milled sphagnum peat moss. Gently shake the box so that all tubers are surrounded by moss. Store them in a cool, dry room with a temperature between 60-75 degrees Fahrenheit over the winter. Plant them in late spring or early summer.
Note: special thanks to Steven Chamblee, chief horticulturist, Chandor Gardens.
What is causing brown spots on the leaves of my bougainvillea?
Leaf spots on your bougainvillea can be caused by fungus. Remove all affected parts of the plant, as well as any leaves that have fallen at the base of the plant. Spray the plant with copper sulfate or other fungicide appropriate for bougainvillea. When watering, focus the spray on the soil rather than the leaves, and maintain good air circulation for the plant.
What is causing bark to fall off of my post oak tree?
Hypoxylon canker is a fungus that is present in most hardwood trees, but can become problematic for stressed or damaged post oaks. The fungus infects the circulating cells of the tree and can cause death fairly quickly. As the disease progresses, large patches of bark will fall from the tree. After death, you may see the fungal spores in areas where the bark is removed.
There is no known control for Hypoxylon canker other than maintaining healthy trees. Trees that have died of the disease should be removed. Wood of a dead tree is much lighter and will break during wind, snow or ice.
Note: special thanks to Dr. Jerral Johnson, professor emeritus, Plant Pathology and Microbiology, Texas A&M University.