The following question and answer columns are currently written by B. Rosie Lerner, Purdue Consumer Horticulture Extension Specialist and are distributed to news media around the state by the Purdue University Agricultural Communications. Columns from June 1995 - January 2006 were authored by Bev Shaw, Advanced Master Gardener.
Q. I have four large trees in my backyard, causing quite a bit of shade. There is a pine, an oak, ash an and a maple. The lawn is too dark for grass, and the quantity of leaves is overwhelming in the fall. I’d like to take down one tree but can’t decide which one. I don’t feel particularly attached to any, although the pine screens the neighbor’s yard somewhat. All seem to be roughly […]
Q. I have a problem weed. It is rubbery with teardrop-shaped leaves. I’ve noticed it will reroot itself when thrown on the ground. It is very hard to kill. In fact, I think it thrives on Round-Up. Can you help? — Teresa Allman, United REMC A. The green, rubbery leaves of purslane are one-half to 1.5 inches long on thick, reddish-green stems. It sometimes bears yellow flowers, and the seeds are borne in a small […]
Q. My Siberian iris plants grow and bloom well, but the plants have a dead spot in the center of each clump. What do I do? — Caryn Hildreth, Lafayette, Ind. A. Many perennials, including iris, grow in an expanding circular pattern. This is their way of spreading to new locations. This growth pattern usually leaves behind a dead center, which works to the benefit of the plant since the new growth is more vigorous […]
Q. How deep should mulch be at the base of a tree? I usually put a light coating around the trunk, in a circle, but I see some professional landscapers making big mounds. Does that keep more moisture in? — Shirley North, South Bend, Ind. A. Generally, a layer of mulch should be 3-6 inches deep, not a volcanic pile like you see around some trees! Even at this reduced depth, it should be pulled […]
Q. My iris were beautiful with lots of flower buds this year, but just about the time they were in full bloom, the heavy rains came and knocked all the tall, blooming stems to the ground. Is there any way to prevent this? — Wendy Lacrosse, Fort Wayne, Ind. A. Many plants can be pinched early in the season to increase branching and reduce lodging, which is the fancy word for crashing to the ground. […]
Q. I have 6-year-old flowering dogwood trees that have never bloomed. The foliage looks healthy each year. What do you suggest? — Carrie Ehresman, West Lafayette, Ind. A. It does take a dogwood a few years to become established, and we don’t make the job any easier for them. Drive through Southern Indiana and notice where the dogwoods are growing. They’re nestled into the edge of the woods where they receive shade and protection from […]
Q. My bearded iris looked big and healthy but barely bloomed. What could be wrong? — Melissa Eddy, Lafayette, Ind. A. Several factors may contribute to a lack of iris flowers. The most surprising is that the rhizomes have to be exposed to sun. They should be planted horizontally, with only the lower half in the soil. It’s easiest to dig a hole and then create a ridge for the rhizome to lay on. Cover […]
Q. For the last 5 years or so my zucchinis have failed to set fruit. They blossom prolifically, but show no sign of fruiting. I have tried different varieties, different environments (even planted one-half mile away) with the same result. No one seems to have heard of this problem. I have tried insecticides, no insecticides, lots of water, little water but still no results. I used to always have a huge crop. — Bill Michaels, […]
Q. I have a small greenhouse that I use to winter over plants and to start new ones from seed in the spring. Each year I get whiteflies. I have bought commercial sprays from lawn and garden departments, but even with repeated applications, the whiteflies seem to persist. What is the best method to rid my greenhouse of these pests? Is there a prevention I should implement? Are there certain plants that attract whiteflies? — […]
Q. We decided to build a sunroom this winter. Unfortunately, this means moving some hosta. Can I transplant them at this time of year? Some others are planted where they will be run over by heavy machinery. Since they’re dormant, will they survive? — Jeff All, West Lafayette, Ind. A. Transplanting in the winter can be hard, cold work. If the ground is not frozen, dig up each hosta clump, and sink it in the ground […]