Time to plant cool-season vegetables
Cool-season lettuces, mesclun mixes and other greens that were planted in early spring may be planted again. If the weather is unusually hot, plant these greens in partial shade or wait a few days until there is a cooler forecast.
• Peonies are dependable, long-living, hardy perennials. Their neat foliage stays green from spring until frost and follows large, showy blooms. They do best in full sun, although they can tolerate partial shade. Flowering is reduced if placed in the shade.
September into early October is a good time to plant peonies, as well as divide and transplant existing ones. Lift the roots carefully and use a sharp tool to cut the large, fleshy roots into smaller pieces. Be careful not to make these pieces too small as each section should have at least three eyes. The eyes are reddish, growing buds that emerge from the top of the roots. You will find them in spring and fall. Set these divisions an inch or two below ground.
• Plants that prefer acidic soil conditions like rhododendrons and azaleas can benefit from an application of granular sulfur to the soil in fall. If your blue hydrangeas have turned pink, then sulfur applications may return the flower color to blue.
Avoid contact with the sulfur by wearing latex gloves and keeping dust out of your eyes. Apply to the soil and gently scratch in. Sulfur works slowly in the soil and repeated applications may be necessary from year to year.
• Allium or ornamental onions are some of the best for resistance to animal browsing and come in many varieties. Try the popular June-blooming Globemaster with a 10-inch pinkish-purple flower on a 2- to 3-foot stem; it lasts up to a month.
The drumstick onion, Allium sphaerocephalon, has reliable burgundy blossoms about 1-inch wide. Allium moly, lily leek, is a small species that is 10 to 14 inches tall with yellow flowers.
These are just a few of the many alliums that will succeed with little effort in Midwest gardens if planted this fall.
• Daffodils are also easy to grow and are resistant to animal browsing while tulips and crocuses are readily eaten.
• Tim Johnson is director of horticulture at Chicago Botanic Garden, chicagobotanic.org.