Dear Dr. Dirt: Do you know why Oakleaf hydrangeas are not very good this spring? I have lost a mature one — been there for years — and another is looking puny. — Margaret, Indianapolis

Dear Reader: This beautiful shrub is considered hardy in zones 5-9. Central Indiana is in zone 5, which means it would be wise to plant the Oakleaf hydrangea in a somewhat protected area like an east exposure where the soil is moist, well-drained, fertile and 50 percent shade. In February, the temperatures were unseasonably high causing many plants to break dormancy. Then winter returned in March, causing plant injury. Perhaps this is the reason for the failure of the Oakleaf hydrangea. It does have a few pest problems, but none are serious. Fertilize weakened plants now, and during the heat of the summer, do some watering.

Dear Dr. Dirt: Several years ago, I planted a weeping crabapple and it had pea-size fruit. Now, there are some branches with fruit the size of golf balls. What is going on with the tree? — Charles, Indianapolis

Dear Reader: Crabapple trees are grafted. Thus, the top (variety) is different from the roots. If you look closely, you will find that the branches that have large fruit coming up below the graft. Prune away these shoots to maintain the shape and quality of the tree.

Dear Dr. Dirt: We have a little fruit garden and the apple trees are losing a lot of leaves. Everything else seems to be ok. What do the apples need? — Kelly, Carmel

Dear Reader: The apples need some dry weather. The record spring rainfall encouraged the number-one apple pest, which is scab. You will find both apple and crabapple trees dropping leaves. Typically following bloom, apples are protected by five or six cover sprays (fungicide and an insecticide) applied every 10 to 14 days. This year, the rain would have, or did, wash away any sprays. Thus, you are going to have a lousy apple crop. However, the apples probably would make good cider, if you have a cider press.

Dear Dr. Dirt: What is the beautiful red maple in the fall? I would like to plant one. — Joan, Indianapolis

Dear Reader: Just about everyone loves the red fall foliage color, and when it comes to trees, the native red maples, Acer rubrum, are outstanding. For fall foliage, the area to visit is northeast New York and the New England states with red maples and white pines. Red Sunset and Red Pointe are in the 40-by-30-foot size range and they typically have outstanding red fall foliage. You will find small trees at larger garden centers and nurseries. They are relatively easy to transplant and they have a medium growth rate.

Dear Dr. Dirt: I love myrtle, but I can't keep the grass out of it. Is there a spray that will stop the grass and save the myrtle? — Debbie, Indianapolis

Dear Reader: It is often hard to establish low-growing ground covers because of weeds. Ortho Grass B Gon will take care of the grass and not harm the myrtle. It can be sprayed right over the ground cover. However, before using any pesticide, it is always wise to read and follow the product label directions. If you do not mind getting down on your hands and knees, you can apply Roundup individually to the grasses and weeds.

Dear Dr. Dirt: I have been battling lawn diseases for the past 11 years. The lawn gets about eight hours of sun per day. Is there a good disease-resistant grass? — Leslie, Indianapolis

Dear Reader: The newer bluegrass varieties offer the most disease resistance. However, just because they are resistant does not mean they will not have some disease.

If you want to start over, eliminate (Roundup) the existing grass and plant one of the newer turf-type tall fescue grasses. They are deeply rooted and have a wider blade than bluegrass. These fescues do no mix well with bluegrass and ryegrass, because of the wider grass blades.

Dear Dr. Dirt: Suddenly, our lawn has some small pink spots. What do I need to do to fix it? — Julie, Indianapolis

Dear Reader: With all the rain and relatively cool temperatures in April and May, the grasses thrived and actually ran out of gas (fertilizer) in some lawns. As a result of low fertility, the disease Red Thread pops up. An application of turf fertilizer should solve the problem.

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