Q. I have some yucca that has turned yellow and has little black bugs on it. What can I do? It starts out green, then turns in the middle of summer. – Grace Griffin, Memphis, Ind.
A. The yucca plant bug is a small blue-black bug with a reddish head. The adults and nymphs hurt the leaves by sucking the plant sap, causing the leaves to turn yellow and stippled. Treat with insecticidal soap, horticultural oil or malathion. Always read and follow label directions, rates and timing of applications.
Q. We have red rhubarb plants that have problems. We transplanted and fertilized them. They grow in spring, then something starts to sting them and they deteriorate. We do have bee hives, but we never see bees on them. We would like them to produce better. – Mrs. Glen Morehouse, Milford, Ind.
A. Rhubarb is sometimes attacked by rhubarb curculio. These rusty-colored snout beetles bore into stalks, crown and roots, leaving spots. Keep beds well cultivated, because curly dock harbors the rhubarb curculio. Removing weeds should control the stalk borer and curculio, both of which work in the stem of the rhubarb plant.
Follow good cultural practices (proper water, fertilizer and weeding) to encourage abundant foliage growth after the harvest season. This is an important plant growth period, because the food manufactured in the leaves is moved and stored in the roots for the following year’s growth.
Q. We just moved into a townhouse so space is at a premium. The backyard is 23 feet in length and is very soggy. Part of it is deck, but a large part is grass. We have a large dog that stays in one corner but walks around the perimeter of the yard. The sun does not reach the yard. Do you have any suggestions regarding landscaping around the fence? What plants and grass will grow in such an environment? -via e-mail
A. There are plants to choose from that will tolerate the moisture and shade. There are thousands of cultivars of hosta with a variety of variegated leaves, corrugated foliage and fragrance. You should have a good time selecting ones that you like. Most hosta achieve full leaf size and interest after growing in your garden for several years, so look at photographs of mature clumps, instead of the foliage in a pot at the garden center, when you make your choices.
Goatsbeard (Aruncus), Pigsqueak (Bergenia), Bugbane (Cimicifuga), Solomon seal (Polygonatum) and Hellebore (Helleborus) and many ferns are perennials that will tolerate your light and moisture conditions and bring interest and texture to your garden. Shrubs for the yard include willows, dogwoods, and summersweet (Clethra). As you can see, the moisture and shade leave you with an acceptable list of plants.
The tricky parts are the grass and the dog. If you want grass, seed the lawn area with a seed mix specifically designed for shade, and consider limbing up overhead branches to increase the available sunlight. If the shade is unavoidable, you may need to overseed on an annual basis, or consider a groundcover, like chameleon plant (Houttuynia) or ribbon grass (Phalaris), if the dog won’t damage it.
If the dog actively lives in the space, it’s almost impossible to garden as well as you might hope. Consider a large, mulched oval in the center of the yard, surrounded by shrubs and perennials for interest, instead of trying to keep the dog off the groundcover or grass.