Brief spells of drizzle on summer mornings in late July gave gardeners the illusion that we're not in the dry end of the season. But generally, the rain gauge stays empty during August. If you take a trowel and dig around almost any shrub, you'll find soil dry at the roots.
Don't neglect rhododendrons during August. This time of year, they are setting buds for the spring show, and watering deeply every two weeks will help them "look ahead to bloom." Two times this month, soaking the soil long enough to reach roots, is vital. That's a lot better than dampening the top ¼ by quick watering. It's fun to stand outside on a hot day with a hose in hand, waving water at plants, but this method, though it cools off bare feet, doesn't do much for plant root needs.
August is a good month to take a break from the garden and wander in a nursery
to get new planting ideas. This month finds many of the earlier perennial flowers
gone. Peonies now consist of just bunches of leaves; early poppies are gone.
When you visit the nursery, look for plants to add to pep up the August and
September garden. I always think that a beautiful garden in September takes
more planning than a gorgeous garden in June.
When you get around to planting and transplanting in September and on into fall, don't forget soil preparation. A great benefit to water retention is compost added to the soil, and mulch placed on top. I use 2-3 inches of organic mulch, applied in spring and again in late fall.
Perennial grasses look their best in September and October, especially after
warm weather boosts production of seeds that give the plants their fluffy-topped
beauty. A fine grass, tall enough to be planted in a row for about a 6 foot
screen, is feather reed grass (Calamagrostis acutiflora 'Karl Foerster').
It's drought tolerant, survives local winter weather and has spectacular garden
presence. (Without being a thuggish plant that takes over.)
One more good grass for drier gardens is blue oat grass (Helictotrichon sempervirens) that sets off flowering day lilies or brilliant cosmos. A good new annual cosmos seed, available from Thompson and Morgan, is Cosmos sulphureus 'Polidor,' in surprising shades of orange, lemon yellow, and red. (You might want to think about it for 2003.)
More for fall color? Cape fuchsia, which isn't a fuchsia at all, is a South African native that makes a bushy large plant with brilliant late color, typically bright reddish orange or yellow. The flowers cover tall stalks that can reach 3 or more feet in full sun, with reliable drought tolerance. (Phygelis capensis 'African Queen'). Don't try this one in shade (it will grow but sulk and fail to bloom.) A rowdy companion for this plant is Helen's flower, (Helenium autumnale), with sunflower-like small blooms in yellow or deep burgundy. Helen's a tall girl, reaching 6 feet or more, and she too likes sun.
The champion plants for dry summers include a number of broadleaf evergreen shrubs. If you like a feathery, open plant, consider Nandina domestica, called "heavenly bamboo" though it's not related to the common bamboo. Nandina is available in several different cultivar sizes, from small low growers that almost make a ground cover, ('Nana Compacta,' 'Nana Purpurea') to 6 footers in the standard plant, Nandina domestica. Nandina's beautiful all year round, with pinkish spring growth that becomes green as it matures. Foliage looks bronze in winter, and white flowers ripen to red berries in fall. It's a great plant for flower arrangers, and looks good no matter what the summer hot weather.
Enjoy an August nursery stroll with fall color and water saving in
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