Summer Gardening Tips: When to Prune, Mulch and Plant

article image
Learn from last summer's mistakes with these summer gardening tips.

After a season of drought, the water in my pond has dropped by several feet, stranding the Louisiana irises that grow around its former edge. The water lilies have become land lilies. To make up for the lack of rainfall, I have been watering the herb garden all summer. The herbs have been responding joyfully, flopping this way and that. Everything desperately needs to be cut back. Low holly hedges surrounding the herb garden are twice as wide as they should be.

As summer wanes, I see lots of steps I could have taken to prevent the current wild look. A “stitch in time” would have made all the difference, and I’d be looking out over a well-groomed garden now.

If I could do it all over again . . .

I would mulch.

When the herbs are still pushing up and I’ve finished pulling the chickweed, I can actually see the ground to apply mulch. This late in the summer, it’s hard to push sprawling catmint (Nepeta ‘Six Hills Giant’) or overgrown feverfew (Tanacetum parthenium) out of the way to get wood chips or pine straw on the soil. Mulch would have helped ­conserve moisture and moderate soil temperature as well as unifying the plantings visually. I like to apply 2 to 3 inches of light summer mulch early in the year, but this year I never got around to it.

I would edge.

Spring is the best time to cut a sharp edge between the borders and the lawn. When the soil is moist, it’s much easier to cut into the sod, and the resulting edge stays sharp with just minor touch-ups during the summer. Now, the soil has baked dry, and I find myself wishing I had a brick cutter instead of an edger to do the job I put off last spring.

I would prune.

My dwarf yaupon holly (Ilex vomitoria ‘Schillings’) is no longer just encircling my herb garden; it’s encroaching on the herbs. I should have pruned the hedges back severely last February or March. Drastic pruning this late in the season will encourage new growth that may not be properly hardened off by the time the first frost rolls in. I’ve marked next year’s calendar for the first balmy day after Valentine’s Day; I’m renting a gas-powered hedge trimmer to shape things up in a hurry.

I would stake.

If only I had pushed some bamboo stakes down into the earth when I planted my lily bulbs last spring and fitted some tomato cages around the young growth of thalictrums, angelicas and delphiniums when they were still small. It’s difficult to go in after the fact and “corset up” mature plants. Some of the lilies have soared to 5 and 6 feet in height. When they’re upright, they look grand, but a windstorm or a severe thunderstorm can break the stalks. Early staking could have prevented this heartache.

I would plant more herbs.

At the end of August, the prettiest sight in the herb garden at the ­Birmingham Bo­tanical Garden in ­Alabama is a brilliant display of flaming red pineapple sage (Salvia elegans), hot yellow Mexican mint marigold (Tagetes lucida), and bright purple velvet sage (S. leucantha). I know just the spot for that vibrant combination in my garden next year.

I also intend to include more of the unbelievably fragrant flowering ginger to sweeten up my garden. It’s hardy in Atlanta and spreads easily when planted in a moist location. Although it’s rated hardy only to Zone 9, I’ve grown the white Hedychium coronarium in my Zone 7 garden for years. Now I want the red H. coccineum as well.

I would plant more annuals.

Although annuals have fallen out of favor with some gardeners, you just can’t beat them for providing color from one end of the summer to the other. Fan flower, globe amaranth and dwarf pink cockscomb all add a certain oomph when planted among the more sedate herbs. Wave petunias from Australia, tough enough to withstand any drought once established, are a sea of colorful trumpets in hot pink or royal blue throughout summer’s hottest weeks.

In August and September, deep blue flowering sage (Salvia guaranitica ‘Black and Blue’) comes into its own. In fact, if I had put some in last spring, I would be enjoying their fireworks now. S. uliginosa is a powder blue nonstop bloomer: S. ¥sylvestris ‘Mainacht’ has deep, dark ­violet-blue flowers that bloom all summer.

I would plant vines.

I wish I had a white cloud of sweet autumn clematis (Clematis terniflora) festooned over my arbor. It grows so rapidly that it would probably be blooming now if I had planted it last spring. It’s a sentimental favorite: my two sons were born in August, and my husband brought sprigs of clematis vine to the hospital both times. At least, my golden hop (Humulus lupulus ‘Aureus’) looks good as it covers the arbor with its papery, shrimplike blooms.

I would plant sage. All is not lost –I can plant bulbs.

At last, bulb houses are advertising fall-blooming bulbs in their spring catalogs, and there’s still time to plant some for bloom later this fall. I’ve just ordered three dozen bulbs of saffron crocus (Crocus sativus). The light purple blossoms with their valuable orange stigmas will peek out from beneath pink Japanese anemones (Anemone tomentosa ‘Robus­tissima’) next to a clump of society garlic (Tulbaghia violacea). I’m planting Colchicum ‘Waterlily’ and plenty of naked ladies (Lycoris radiata, L. squamigera), so called because they send up flower stalks bearing lilylike trumpets but devoid of leaves. In later winter, naked lady bulbs send up leaves that persist until summer.

I’m also adding an Oregon native camas, Camassia cusickii, which I spotted in a friend’s garden in Nashville last spring. It will add lovely blue spikes to the April herb garden.

I can plant annuals now.

Now is the time to start seeds of ­biennials so that they will overwinter as rosettes and throw tall flower spikes next spring. The soft pink foxgloves ­Digitalis purpurea ‘Apricot’ perfectly match the color and bloom time of my climbing ‘New Dawn’ rose, but I’ve never seen the plants for sale so I’ll start seeds now and move the transplants into the garden. Dame’s rocket (Hesperis mat­ronalis) and hollyhocks (Alcea rosea) are best started now, either in flats or sown directly in the garden. Clary sage (Salvia sclarea) grows luxuriantly if started in ­August, and this year I’m planting curly parsley (Petroselenum crispum ‘Champion Moss Curled’) in with my pansies for a spot of bright green.

With the best of intentions, Geri Laufer juggles family, writing and gardening at Frog Holler outside of Atlanta.

Mother Earth Living
Mother Earth Living
The ultimate guide to living the good life!