Wednesday, May 13, 2009
You get what you pay for
John Arbogast
Landscape consultant John Arbogast answers your questions every Thursday. Send questions about your lawn, garden, plants, or insects to:
Dear John
5102 Greenfield St. SW
Roanoke, Va. 24018
Or send an e-mail. Answers will be given only in this column. Please don't send pictures or samples.
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The lawn is 5 years old now. This off-brand weed and feed appears to have eradicated the clover amazingly enough but now I am left with patches of light green grass in its place. Is this just new grass that will green up throughout the summer? Or, do I have a new problem? The rest of the lawn is a nice dark green except in these light green patches.
Do I need to use something like Ironite? Which I read is full of lovely chemicals.
A: Your light green grass that will not turn dark green with an application of iron.
My first recommendation is that you take a complete sample of this light green grass to a local turf expert to have the type of grass identified and get recommendations made on how to deal with it in your lawn.
There are some weedy grasses that have an apple-green or light green color by nature. One of these could have taken over the bare places in your yard where the clover used to be.
Because this light grass came in so quickly following the death of your clover, it might be Poa annua. The seeds of this weed grass germinate readily when sunlight becomes available. Poa annua loves to grow with short mowing height, so raise the cutting height of your lawn mower.
Poa annua also loves to grow on wet, compacted soils, which are conditions that clover also likes. Poa annua occurs in cool temperatures, which we have had here in Roanoke this spring.
Or -- this light weed grass could be what is called “rough bluegrass,” which has a shallow root system and can grow on wet, poorly drained sites.
Follow recommendations that come from your local expert. It is difficult to eradicate an unwanted type of established grass that is growing in another established grass. Poa annua is especially difficult to get rid of, as golf course greens keepers can attest.
You should core aerate your lawn in the early fall. Remove grass clippings from mowing when any weed seed heads are present. Poa annua is a prolific seeder. Take soil tests from your lawn, especially to check for an adequate level of phosphorus.
Q: I want to plant a few shrubs near my driveway, but the soil where I will plant drains poorly. It obviously is a heavy clay soil. What can I do?
A: Don't dig the shrubs' hole as deep as the root ball. Make it only deep enough to leave about one-third to one-half of the root ball will be above the ground.
After placing each root ball into such a hole, pull soil up around the root ball to create a little mound. Mulch that soil with 2 to 2-1/2 inches of organic mulch.
Try to divert rain and irrigation water from the shrubs. Use lines of black corrugated tubes that can carry water off a wet site to a proper outlet.
