Q: We can spend just two months at our vacation home on the New Jersey shore. Which sunny plants can tolerate 10 months of neglect and still flower in July and August? — Carol Mays, Philadelphia, Pa.
A: The dog days of summer are a challenge for any garden. The only truly no-maintenance summer bloomers I can suggest for you are blush-pink summer sweet (Clethra alnifolia) and rugosa roses, both fabulously fragrant. Since you won’t be there to put in and care for annuals, consider planting perennials for mid-summer and late-summer color, and try what I call “prubs,” semiwoody shrubs that should be cut down to the ground each year like perennials because they flower on the wood produced that growing season. However, even the toughest, least demanding of these plants will need a little cleanup work in early spring to look and grow their best. (Try to arrange for a local yard service to come over for a day to prep the area for you.) With just a few hours of work in the spring you can have beautiful summer blossoms from colorful native plants and a few introduced ones that have adapted to the area.
Your soil is probably sandy, nutrient-poor and somewhat acidic; dig in some compost, well-rotted manure and perhaps a little lime before planting. Orange butterfly weed (Asclepias tuberosa), the red and gold daisylike Indian blanket flower (Gaillardia x grandiflora ‘Goblin’) and the deep blue spikes of long-flowering Veronica alpina ‘Goodness Grows’ make a rich summer composition, with the burgundy foliage of crimson barberry (Berberis thunbergii ‘Atropurpurea’) as background. A bit later, the brassy daisylike heads of Rudbeckia fulgida var. sullivantii ‘Goldsturm’ and the reddish-purple spikes of gayfeather (Liatris spicata ‘Kobold’) will echo the textures and colors of America’s late-summer wildflowers. If cool colors are more to your taste, let prairie winecups (Callirhoe involucrata) sprawl through powder blue Stokes’ aster (Stokesia laevis). A backdrop of fragrant prubs might include purple butterfly bush (Buddleia davidii cultivars), blue chaste tree (Vitex negundo) and the lavender-blue haze of Russian sage (Perovskia atriplicifolia). Allow the native lipstick-pink beach pea (Lathyrus maritimus) to clamber through them. With a bit of extra water, the great trusses of garden phlox could be a standout. Phlox maculata ‘Alpha,’ ‘Omega’ and ‘Rosalinde’ are your best bets for mildew resistance. Consider a native coastal mallow just recently “discovered” for garden use, Kosteletzkya virginica. It has huge, luscious, pink hibiscuslike flowers and, miraculously, doesn’t get devoured by those metallic orgiasts, Japanese beetles. Self-sowing annuals such as the tiny-flowered signet marigolds, moss rose, California poppies, cleome, old-fashioned seed petunias and Verbena bonariensis can help out with their delightful colors in the most unexpected new spots each year.