In the Garden
Ralph Purkhiser, Purdue University Master Gardener
Anyone who has been reading the column for very long knows that I am not big on turf lawns. I certainly do not desire a golf course look for my lawn. I actually love having clover, plantain and other broadleaf plants in my lawn. However, I do like for the turf to be healthy enough to maintain some green color over the winter and to have enough grass to keep things from getting muddy. Whatever type of lawn you desire, September may be the most important month for lawn care.
Fertilizing your lawn in the fall is far more important than spring applications. However, the fertilizer used at this time needs to be one with a higher third number, promoting good root growth. Grass needs nitrogen, but at this time, the root growth is more needed than leaf growth. Good roots will get your lawn through the winter. Most lawn-care experts recommend fertilizing in September and again in late October or early November. The lawn will keep growing, even after a frost, until the surface freezes.
If you are looking for that perfect grass lawn, fall is also the time for applying a broadleaf herbicide. Many common lawn weeds actually germinate in the late summer or early fall, then go dormant in the winter and re-awaken in the spring. Such weeds will continue to absorb herbicides until frost.
Fall is also a good time to plant a lawn, whether doing so to thicken an existing lawn or starting a lawn in a new place. Your existing lawn may need more good turf grass. Seeding into existing turf will help thicken a lawn. I recommend aerating the lawn before planting. The seed will make better soil contact with the slits left by aeration. Another good method for over-seeding is to rent a power seeder that will power the seed into the soil. Choose a quality grass seed. Some seed companies have special blends for fall planting. Once seeded, it is important that the lawn be watered frequently if rains are not sufficient. When the new grass is about five inches tall, begin mowing to a 3-inch height and continue to mow until the lawn stops growing.
The other fall lawn task has become a bit more controversial in recent years. Most lawn-care professionals still recommend removing all of the leaves from a lawn. Wet, matted leaves may smother turf if left over the winter. However, many now recommend simply continuing to mow, chopping the leaves into small pieces that will decompose in place, adding organic material to the lawn. As long as the leaf layer is not too thick, this mulching option seems to work well. However, a lawn covered by thick, heavy leaves may need to be raked. Instead of bagging the leaves, though, I recommend raking them into flower beds, where they will compost in place through the winter.
At Sandhill Gardens, the late summer blossoms are beginning to shine. The re-blooming azaleas are doing better than they have ever done. Several patches of colchicums, also known as autumn crocuses, have peeked through this week. Caryopteris, or blue beards, are near peak and the potentillas are full of blooms. It looks like it will be a good late summer/early fall flower show. Coming up on September 28, I will be hosting a Century Celebration at Sandhill Gardens. My maternal grandparents moved to this place October 1, 1924, and several ornamental plants that my grandmother set out then are still thriving. The celebration will not be fancy, but there will be a plant exchange beginning at 10 AM for anyone who wants to trade plants with other gardeners. Fall is a good time to plant perennials. I will have a fire in the fire pit if anyone wishers to bring hotdogs or marshmallows to roast. Otherwise, just come and sit a while in the gardens or watch the sunset from the top of the cliff. If you are in good shape, you may even want to walk down to the cave. It really is a place of unique beauty.