Hard to believe August is right around the corner. Here’s your garden checklist for the month.
Woody plant care
Now that the many rain storms that we saw earlier in this season have reduced in frequency, it is important to remember to keep our woody landscape plants supplied with adequate water. Weekly watering of newly planted trees and shrubs is necessary if natural rainfall is insufficient. Watch closely for signs of scorch (browning) on tender new foliage.
Monitor newly planted trees and shrubs for insects and diseases. Succulent new growth is very attractive to insects. Any late-flowering shrubs should be pruned immediately after flowering. No other pruning is recommended in August.
By mid-August, the fertilizing of roses should be stopped.
Annuals and perennials
Deadheading of annuals and perennials is very important this month as it encourages the continuation of their flowering.
Container gardens and hanging baskets will need to be watered frequently during the hot weather. To increase blooming and produce lush foliage, fertilize twice a month with a quarter-strength liquid balanced fertilizer.
Yellowed and dried stems and flower stalks of Asiatic lilies should be removed by gently pulling or clipping to separate them from the underground bulb.
August is a good time to assess your current garden and make plans for next year’s garden design. When planning your next garden, remember to take into account the ease and sustainability of perennial native plants.
In 2010, I planted a half mile of roadside wildflowers during a road construction project in our neighborhood. Little by little the previously established grasses began to reclaim the area. However after three years, it is becoming apparent that the grasses are in for a fight as the newer native plants continue to appear in ever-increasing numbers each year. Native plants are tenacious. The primroses, wild phlox, coneflowers and black-eyed Susans are thriving in large clusters. If they can survive in a roadside situation, just think how successful they will be in a home garden. Native plants carry the added bonus of being a major attractant for the butterfly populations that pass though our yards in July and August.
Mid-to-late August is the best time to seed bare areas in your lawn. The approved seed for most lawns in northern Illinois is a mix of Kentucky blue grass, perennial rye and fescue. Keep the area moist until seeds germinate.
Do not fertilize lawns until September.
Fruit, vegetable and herb care
Snap beans, broccoli, cabbages, cauliflower, carrots, spinach and radishes can be planted during the first week of August for autumn harvest.
To increase flavor, harvest squash before they become too large.
Monitor edible crops for insects and disease but avoid strong insecticides and fungicides on food products.
You may have noticed in your own yard or elsewhere in the area that pine trees are turning brown and dying. What is causing this sudden death of pine trees? It is a disease called pine wilt.
Pine wilt has been fairly recently diagnosed. The disease is caused by the pinewood nematode. Illinois is experiencing a dramatic increase in the numbers of cases of this disease. Pine wilt in Illinois is most common in Scotch pine but also has affected arborvitae trees.
Pine wilt presents as a sudden decline followed by the death of the entire tree within a few weeks or months. Needles turn from a gray green to yellow to a total brown during the late summer and into the late fall.
Remove dead trees to the ground and destroy. Do not store the wood from diseased trees for firewood or use as a mulch for your gardens. This will break the disease cycle and prevent further spread of the problem.
When planting new conifer trees, select Norway or blue spruce, Douglas fir, cedar or hemlock as they are immune to the pine wilt disease.
• The Master Gardeners are available to answer your gardening questions from 9 a.m. to noon Monday through Friday at the University of Illinois Extension DeKalb County office located in the Farm Bureau Center for Agriculture, 350 E. Prairie Drive, Sycamore. Call 815-758-8194 or email DeKalb_mg@extension.uiuc.edu. Walk-ins are welcome.