8/11/17: In the garden this week


Some clients resist planting native grasses; resistance usually ends when they see the colors of little bluestem (Schizachyrium scoparium). Look carefully at the blues and purples in this plant, and remember that every plant is slightly different.

We are into what I think of as the summer doldrums, or maybe just a reli=atively q uiet period in the garden. Certainly the prairie perennials continue to bloom with all their might, and there are all the asters to look forward to, but in the ornamental garden there’s not much to do except to keep things tidy (that is, if you like your garden to be tidy).

Still, there’s always something to do in the garden, and here are some suggestions:

water new plantings: unless we get a decent amount of rain this weekend (and forecasts do predict rain), go ahead and water newly planted grasses, shrubs, and woody plants. We received just under an inch of rain so far this week. Remember that perennials and woody plants that you planted this spring or last fall need supplemental water during dry periods throughout this growing season. The rule of thumb is at least an inch of water per week for newly installed plants. In dry weeks throughout the growing season (weeks with less than an inch of rainfall), you need to water all plants installed this spring or last fall. How do you know when we’ve received an inch of rain? You can make a highly sophisticated rain gauge–an old plastic container or tin can placed among the plants. I total the weekly rainfall and decide whether to water my new trees or my clients’ new plantings each week.

— if you intend to plant a second crop of cool-weather vegetables, you should be buying and starting seed. Water the vegetable garden deeply during dry periods, particularly when the weather is hot, and watch carefully for pests and diseases. Removed diseased plants promptly to prevent spread. Continue to remove the flowers from basil plants as they form; you should already have cut down the plants once to make pesto.

— be sure to properly tie, stake, and prune your tomato plants. Most tomato cages are much too small: the plants outgrow them before they start to bear fruit. And unless tomato plants are properly pruned, by pinching out the suckers, they will be so bushy that they’ll be especially susceptible to fungus infections like verticillium wilt. You’ll find general guidelines for growing tomatoes here and specific watering instructions here.

—  It’s too late to plant. Wait until the weather turns cool in fall. During hot weather, plants put their energy into top growth and blooming rather than growing new roots. If you do continue to plant, water very thoroughly and keep an eye on those new plants. They will need extra water during dry periods, as explained above.

it’s a bad time to fertilize your lawn or to reseed bare patches, no matter what your lawn-care service tells you. Lawn grasses are adapted to much cooler summers than we experience. All they want to do during this time of year is go dormant, so they really can’t use any extra nutrients. Here’s a suggestion: don’t feed at all this year. The lawn will look just fine. Or wait until around Labor Day and use one application of a slow-release organic fertilizer. Avoid pesticides, fungicides, and herbicides. Pesticides kill butterfly and firefly larvae and native ground-dwelling bees as well as “bad” insects. And garden chemicals are not so great for kids or pets either; common herbicides, in addition to killing butterfly host plants like violets, are carcinogens. Best to avoid them.

— it’s time to prune woody plants. You want to prune when the plant is relatively quiescent—when it’s not using a great deal of energy growing, flowering, and fruiting that it has little to spare to healing a wound. This will happen between now and leaf drop in fall. Basically, when you see that the plant has finished fruiting and that it has formed next year’s buds, but the leaf color is not fading yet, you have a window of time for pruning. Of course, you should prune diseased or injured plants at any time as well as remove any safety hazards, such as overeager shrub that block sidewalks or diseased trees that might fall down.


A branch of a large native hazelnut shrub (Corylus americana). It has finished setting fruit as well as forming next spring’s flower buds–the tiny things hanging down from the leaf nodes will become the male flowers. The plant is resting before its last remaining task of the year, leaf abscission, so this is a good time to prune.

do not deadhead your perennials. It will soon be time to collect seeds, which represent winter food for birds and other creatures and new plants for you. Store your seeds in a cold place (such as an unheated garage) for next year’s planting or simply scattered on the ground where you want them to grow. Do deadhead potentially  invasive plants like butterfly bush, however.

Enjoy the garden this week!


Rudbeckia triloba is in bloom now and will put on a display through September and into October. This is a short-lived perennial that readily self-seeds, so new plant appear each year. It remains a manageable 3 feet tall and doesn’t spread aggressively. And the flowers are adorable!




Winter color for a gloomy day


Coralberry (Symphoricarpos orbiculatus) will display these gorgeous pink berries for most of the winter. This is a great thicketing shrub for difficult areas–low-growing and tolerant of everything but wet feet.


I planted this dwarf cultivar of Hydrangea quercifolium in a shady spot last spring, and I’m surprised at how pretty it still looks.


This large American holly, Ilex opaca, grows outside my office window, and the bird activity it attracts in winter is continually entertaining. This tree was here when we bought our house, and I don’t know where the male is.


Little bluestem (Schyzachrium scoparium) is beautiful all year, not least in winter. Soon the seeds will be gone; birds visit the plants continually. Notice the Rudbeckia seeds peeping through.


Male catkins of American hazelnut (Corylus americana) are prominent all winter; the tiny, bright red female flowers will be visible for only a few days in early spring.