By Pete Prown
Mid-summer is a notoriously tough time in the garden, the moment when your ornamental plants show early signs of stress and heat damage. But there is hope. Bill Thomas, executive director at Chanticleer Garden in Wayne, Pa., once told me that the best strategy for mid-summer color involves, “The three H’s – hydrangea, hibiscus, and heptacodium.” These are all tough performers that can beat the heat and produce much-needed color in July and August. Other choices include daylilies, St. John’s wort, buddleja, smoke bush, crape myrtle, and a host of other heat seekers.
Your May plantings of annuals should be reaching their zenith, especially since we’ve had a steady cycle of rain, followed by heat and sun, in Delaware County. If you were lucky enough to visit the Swarthmore Horticultural Society’s salvia sale in spring, you’re likely reaping the fruits of your labors, as both the annual and perennial cultivars they offered are blooming wildly now. If you missed it, make sure to grab some new salvias for your 2017 garden, either perennials to plant this fall or new ones for next year. Salvias are superior and rugged summer champions.
You may notice, however, that even with regular deadheading, some tender annuals such as petunias are starting to get leggy in the heat. At this point, you may want to bite the bullet and cut them back, hoping for a Labor Day comeback. Or do what many garden professionals do — throw them on the compost pile and replant with fresh annuals.
You may think that this is the expensive and wasteful option, but if you’ve ever been to a public garden and wondered how they keep their beds, pots, and baskets blooming so profusely all summer long, this is the secret. Local garden centers like Mostardi Nursery, Wolfe’s Apple House, and Linvilla should all have new, colorful annuals available for mid-to-late season replanting. Also check the Swarthmore Co-op.
Now the bad news: weeding. With the regular rain and warmth this month, we’ve seen explosive weed and invasive vine growth in our landscapes. There are precious few shortcuts for weed management, aside from mowing the lawn and deploying the weed-whacker.
The best strategy is to stay on top of the growth with regular effort, pulling ground weeds, cutting down fast-growing vines, and watching out for poison ivy. Even if you just put in a half-hour once or twice per week, you’ll make a difference.
For you vegetable gardeners, a good rule of thumb is to pull a few weeds every time you water or harvest delicious edibles. Before you grab that new eggplant or cucumber and proudly dash to the kitchen, grab a few handfuls of green invaders and compost ’em.
At this time of year, you’ll also want to be handy with the hose. Those trees, shrubs, and perennials you planted in the luxury of spring need an extra drink of water — make sure it’s a generous one, as even a little heat stress in July can conceivably kill them this winter. Same in the veggie garden — don’t assume a passing thunder shower will adequately water the plants. Often, rain doesn’t penetrate very deeply, which is why you need to keep that hose or watering can ready at all times. Certainly, a rain barrel makes practical sense, too.
Last thought — if you’re going on vacation, ask a friend or hire a neighborhood kid to keep watering your tender or newer plants. They’ll thank you for it later on.