PLANTING

Fall-blooming perennials Add autumn color to flower gardens by transplanting gallon-size perennials into beds, borders, and containers. Good choices include aster (all types), Boltonia asteroides, butterfly weed, Chrysanthemum weyrichii, late-blooming varieties of goldenrod like 'Fireworks' and 'Golden Fleece', Japanese anemone (Anemone x hybrida), Joe Pye weed, Origanum laevigatum 'Herrenhausen' and 'Hopley's', prairie sage (Salvia azurea grandiflora), purple coneflower, sedum 'Autumn Joy', sneezeweed, sunflower ( Helianthus 'Lemon Queen' and H. maximilianii), and willow gentian (Gentiana asclepiadea).

Peonies Where space is tight, plant rock garden peonies, which grow just 15 to 24 inches tall and take up much less space than standard varieties. 'Chameleon' has hot pink flowers and gray-green foliage; 'Little Red Gem' has red flowers and filigreed, cut-leaf foliage; 'Rose Gnome' is rosy pink and sweetly scented; 'Royal Tot' is orchid-cerise and fragrant; and 'Squirt' is pure white with golden stamens. They're available from Klehm's Song Sparrow Farm & Nursery (800/553-3715), which harvests them late this month and sells them bare-root.

Rose of Sharon For reliable bloom in late summer, plant heat-loving deciduous Hibiscus syriacus. An upright shrub, it can reach 10 to 12 feet tall and 6 feet wide, and grows in any soil in full sun. Single and double flowers come in many colors. For a longer blooming season, choose rose-pink 'Aphrodite', white 'Diana', white-and-red 'Helene', or lavender-pink 'Minerva'. Early frosts can damage leaves and flowers, but the woody parts are extremely cold-tolerant.

MAINTENANCE

Fertilize roses and other ornamentals At midmonth, feed permanent plantings for the last time this summer. Use an organic product labeled for general garden purposes, and follow package instructions for application rate. To give plants a chance to harden off (adapt to cooler temperatures) before winter arrives, don't fertilize again until after the first hard frost. Continue to feed annuals.

Gather flowers for drying Collect blooms of ageratum, amaranthus, baby's breath, bells-of-Ireland, celosia, globe amaranth, globe thistle, goldenrod, hydrangea, lavender, marigold, pearly everlasting (Anaphalis margaritacea), sea lavender, strawflower, yarrow, and zinnia. Cut flowers with as much stem as possible just before the blossoms are fully open, then bundle the stems with rubber bands. Hang bunches, with flowers upside down, in a dark place until dry.

Harvest vegetables Pick bell peppers when they reach their mature color, broccoli just before the buds open, cabbage after heads are fully formed, cantaloupes with netted and aromatic skin, carrots when they're finger size, corn when the silk turns brown, eggplant when firm and skin is glossy, kohlrabi at 2 to 2½ inches across, onions after tops fall over, new potatoes after blooms form, spinach at any time, and summer squash and tomatoes at any time after fruit forms and starts to color.

photo by Thomas J. Story

Lime foliage and lemon yellow flowers look especially cool together on a hot August day. To refresh a sunny or partly shaded patio, pot up our favorite "lemonade" combo, with the tallest plant (accent) toward the back of an 18-inch container, the filler in the center, and the spillers around the front edges.

Accent Salvia elegans 'Golden Delicious': chartreuse leaves, red blooms in late summer. 1 plant.

Filler Sweet flag ( Acorus gramineus 'Ogon'): golden yellow leaves. 1 plant.

Spillers Superbells 'Yellow Chiffon' calibrachoa: pale yellow blooms. 3 plants. Creeping jenny ( Lysimachia nummularia 'Goldilocks'): light green leaves. 1 plant.

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