7/28/17: In the garden this week


This plant combinations says “the height of summer” in no uncertain terms. The Rudbeckia will be in bloom until September, but the Vernonia (ironweed) will only last a few weeks.

Who says there are only four seasons? To me, we are transitioning from early summer to what I think of as the height of summer: the brightest-colored flowers are blooming, native fruits are ripening fast, fall bloomers such as asters are showing buds, and some late-summer plants, such as great blue lobelia, are coming into bloom. And of course, tomatoes are beginning to ripen fast in the vegetable garden. Here are some not-too-strenuous garden chores for this hot weather (in addition to weeding, made necessary by a season of normal rainfall, in contrast to the past couple of years of drought.

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. 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.

— all vegetables, including tender crops like tomatoes and peppers and corn, should be planted out by now, and it’s time to remove early greens like lettuce and spinach. In fact, if you intend to plant a second crop of cool-weather vegetables, you should be buying seed. Water 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 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 col in fall. Once the weather turns hot, 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 too late to fertilize your lawn or to reseed bare patches, no matter what your lawn-care service tells you. 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 almost 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.

Enjoy the garden this week!


The first blossoms of Hibiscus moscheutos, rose mallow, opened this week in my garden. This native hibiscus is a short-lived perennial that self seeds readily, produces flowers of different colors, and is very easy to grow.