DESIGN AND CONQUER - an astilbe bed all its own
by Ruby Weinberg
Mid-winter is a great time to plan an “all astilbe” garden. Imagine one of your partially shaded beds or borders filled with ferny foliage topped by vividly colored flower plumes of pinks, whites, reds, and lavenders. Just the thought is enough to melt away the snow and ice.
Astilbe cultivars, when planted in a suitable location, are easy to grow. I have found that mixing them with other perennials seems to dilute the intensity of their flower colors, and so, I try to keep my beds pure. However, giving them space all their own requires several considerations:
1. period of bloom
2. variation of height
3. color blending
Bloom: An all astilbe bed could include those that flower from late May through early June followed by some in full flower from mid-June to the end of that month. Then there are others for early July through most of mid-summer with some peaking in August. A few give quite a show in early September.
Height: When designing a bed, the gardener should keep in mind that astilbe cultivars vary in height from dwarfs of 12-15" for edging to those of mid height, 20-24", to the moderately tall, 26-30". Very tall cultivars rise to 36" with one giant reaching 5-6'! In a two sided bed, the central placement of a tall form will balance the planting nicely.
Color Combinations: For some gardeners (I am among them), many flower colors do not blend well together. Dark red blooms, especially, should be carefully placed. I like them best with lots of whites and lavenders. Blooms with peachy tones (such as A. 'Peach Blossom') or salmon pink flowers (such as A. 'Mother Theresa' ) may be lovely in a bed by themselves but with other astilbes, the blooms look to me like bleached laundry.
With all these considerations when planning a superb all astilbe bed, you might be ready to throw in the towel and plant more hostas instead, but consider this:
• Even the tallest astilbes do not require staking.
• The foliage alone is delightful and, in many cases, has lovely bronze tones.
• The flowering stems, when finished blooming, sway in the breeze like slender meadow grasses.
• Deer will usually avoid eating any part of astilbes--unless they are starving.
• Butterflies frequently visit the blossoms.
• Unlike many other perennials, astilbe plants can wait for at least 4 years without needing division.
• Stems of blooming plants make excellent cut flowers.
• Where SOME road salt is present, astilbes do not seem to be adversely affected.
Site: Astilbes are not plants for hot, dry, sunny areas. Light to fairly heavy shade is needed with some peat moss, compost and/or well rotted manure added to the existing soil.
Irrigation: Gardeners are frequently warned that astilbes really need a moist, swampy type of location. The partly shaded area where I have planted my astilbe bed is far from being swampy; however, last summer, 2010, it needed to be watered just once during the entire season. Only if very dry to droughty weather prevails will most astilbes need the extra irrigation.
If your plants are not quite as floriferous as you might wish, then a little more sunshine may be needed. Sometimes, all it takes is trimming the lower branches of a tree near the bed. Just a small amount of extra light may be enough to bring out the best in your plantings. Then, too, several cultivars called 'Visions' are said to tolerate more sun than others and might be plants to try if your proposed planting area has very little shade.
DESIGN AND CONQUER
Careful placement of plants is best accomplished first on paper. In mid-winter, when outdoor gardening projects must wait, time spent designing a part of your garden on paper puts you way ahead on your spring list of projects. Now, if possible, try to get outdoors to measure the size and shape of the proposed bed, and then, back indoors with drawing paper, pencil and eraser, fill in 1/4" circles with coded numbers representing each square foot of space. Repeat groupings of 3 to 6 plants for as many times as you have space in the garden.
Before spring sets in, you can place a mail order to your favorite nursery for bags of astilbes each with 3 bare root divisions. Or, if you prefer, visit one of the better, well stocked garden centers in your area and pre-order 2-quart container plants in time for spring planting. Happily, almost every business selling perennials is certain to stock quite a few named astilbe cultivars and, by ordering early, your preference may influence some of their purchases. Just make sure that it is their practice to carefully label their plants.
Cost is always a consideration, especially these days. If that is a problem for you, plan to first plant a small astilbe bed, and after the second year, you should be able to divide each plant into 3s thus creating more plants for an enlarged bed. Of course, you might also be able to trade cultivars with a friend who grows some of them.
The following, arranged by flower color, height, and season of bloom, are 14 astilbes that I especially like. (There are hundreds more!)
'Bressingham Beauty' 30-36" - mid-summer
'Cattleya' 36-40" - late July/early August
'Visions' 18" - late July-early August
'Pumila' 10-14" - August-September
'Visions in Pink' 18" - late July, early August
'Rhineland' 28" - July, early August
'Purpurkerze' 36" - mid/late August
'Superba' 5'-late August
'Visions in White' 15-18" - mid-summer
'Deutschland' 18-24" - mid spring
'Diamonds and Pearls' 26-30" - July
'Bridal Veil' 30" - July
'Fanal' 24" - June, early July
'Red Sentinel' 24" - June, July; reddish stems
** All photos by Martin Weinberg
More flowers articles
Print this story:
published February 24, 2011