Bonus Gardening Questions
Melinda answers more summer gardening questions.
My hibiscus hasn't bloomed in the 5 years I've had it. I bring it indoors for winter and take it back outside in summer. What else should I be doing? —Deb Schroeder, Stillwater, Minnesota
Melinda: You might want to try using a flowering plant fertilizer beginning in spring through late summer. These fertilizers contain high levels of phosphorus that help promote blooming. Also make sure your hibiscus is growing in full sun or another bright location outdoors. Limit pruning to fall through late winter. Pruning it at other times can delay or even prevent blossoming.
Will the high iron content of our well water harm y perennials, shrubs and vegetables if I regular water during the growing season? —Karen Fiebig, Waterbury, Vermont
Melinda: The iron content in well water usually isn't harmful to common landscape plants. This is especially true where the soil pH is 7.0 (neutral) or higher (alkaline). Iron toxicity is more likely to occur, if at all, in acid soils. If you want to be sure, have your soil tested to determine its pH, especially if you notice unexplained brown spots on your plants. Contact your local county Extension office for soil test information.
I'm worried about two old daylilies in my garden. They've thrived since 1921, but haven't bloomed for the last several years. What can I do to save them? —Marguerite Harrison, Dyer, Tennessee
Melinda: Start by evaluating the growing conditions. Daylilies grow best in full to partial sun, so move them to a different location if necessary. Also check the fertilizers you're using—high nitrogen content can prevent flowering. If neither of these factors is the problem, the daylilies may be getting overcrowded. Give them more room by dividing crowded plants—just dig, divide the clump and replant smaller pieces in several areas. The divisions should bloom for you next season.
I can't seem to grow anything in our lousy soil. I've enhanced it with topsoil and water frequently, but even wildflowers refuse to sprout. What can I do? —Norman Rosenberg, Incline Village, Nevada
Melinda: Try using compost. It will add organice matter to the soil, which improves drainage and increases the soil's ability to hold water. You can make your own compost or purchase it at a garden center. Work several inches of it into the top 6 to 12 inches of your garden soil. You should see improvement during the first growing season, but it takes years to build good garden soil. If you don't want to wait, try creating raised beds instead. Use lumber, plastic timbers or large stones to build a raised garden, then fill it with 6 to 12 inches of quality topsoil. Voila! An instant garden!
After borers destroyed my roses, I decided to start over. How can I keep these pests from attacking my new plants? —Ann Zelonis, Warminster, Pennsylvania
Melinda: Maintaining healthy plants will help prevent borers and other insects. But there are a couple of control measures. For instance, pith borers burrow into rose canes through the pruning cuts. To prevent this, place a drop of white school or household glue on the cut surface.
Stem-girdling borers, on the other hand, are more troublesome. As your new plants grow, try pruning out the older canes (3 years and older). This allows the younger canes, which are less susceptible to borers, to thrive.