varieties

LifeLife AFTERDayLaborDayLabor September 3rd needn’t look like D-Day for fall sales. Here are 12 perennial varieties that will keep your customers’ autumn borders performing through October.

By Ann Hancock

n late August, September and October, there isn’t a lot hap- duced a with deep coloration. This sets off the thousands of pening in most perennial borders. Even the long bloomers, tiny, white, starry flowers that blanket the plant. The petals Isuch as coreopsis, are winding down. While the spring flow- have faint purple tips with centers that are yellow to pink in ers slide into their time of rest and relaxation, the challenge for color. Our are next to a group of Sedum ‘Autumn Joy’ — many of your customers is to get out of the mum mold — to find a the bold foliage and flower clusters of the sedum next to the few plants that don’t look like the expected. There’s a market for aster’s fine texture make a nice pairing and would create an the unconventional, and you can take advantage of it by offering effective display combination in your store. A. lateriflorus is a more fall perennials than just Sedum ‘Autumn Joy’. There are a native plant and has not been troubled by any foliar diseases or number of attractive, late-blooming plants you can offer, and with insect pests. proper marketing, well-organized displays and knowledgable staff to support them, you needn’t despair — there is indeed “Life after A STER TATARICUS ‘JIN DAI’ Labor Day.” This aster is native to Siberia, giving it a The following species have all performed well good hardiness rating. It is a large plant, up to in the demonstration gardens at Michigan State six feet tall, with large . The foliage is University (MSU). Among other things, we are unlike that of many asters, as it consists main- trying some less-common species of aster, ly of a rosette of large, basal leaves (Allan moving away from the rust-prone types that we Armitage has likened them to Swiss chard). In have grown in the past. Some of these plants Michigan, the plant blooms in late September have been featured in previous G P N articles on and October. The flowers are a very attractive, the perennial trials at Michigan State; these medium purple with bright gold centers. Jin plants, as well as a few bulbs, have really Dai, at 3-5 feet, is shorter than the straight impressed me with their long bloom period, and species, making it a bit easier to use in the they deserve inclusion as components of a fall border. The one drawback we’ve found with this planting. Many late-blooming native plants have plant is that meadow voles find the roots deli - also been selected and bred for superior flower cious. and color and production. Finally, while I will not emphasize them in this article, tender A STER LAEVIS ‘BLUEBIRD’ perennials, such as cannas and dahlias (partic- Smooth aster is a native species that seems ularly those with colored foliage), are wonder- remarkably disease free in our garden. The ful, easy-care workhorses in any border and do performance of this aster was good for the first a good job of bridging flowering gaps during the two years, but when it bloomed in its third season. year, Bluebird stopped visitors in their tracks. So many flowers were produced that no foliage A STER LATERIFLORUS was visible, and the display was effective for This plant’s shrubby habit gives it a nice three weeks. We have found that rabbits like presence in the border even when not in this species, so we cage the plants. The leaves, bloom. The foliage is fine-textured, a deep as implied by the name, are not hairy, and are Clockwise from top left: Aster lateriflorus; Aster laevis ‘Bluebird’; green color touched with purple. In Aster tataricus ‘Jin Dai’; Eupatorium coelestinum and Conoclinum a fine, deep green. Garden designer Laura Coit such as ‘Lady in Black’, breeders have pro- coelestinum. (All photos courtesy of Ann Hancock.) reports that Bluebird is far superior to the

58 GPN September 2001 varieties

straight species, even in cultivation. RUDBECKIA TRILOBA COLCHICUM AUTUMNALE Though not a long-lived perennial (some This tough bulb not only blooms in the classify it as a biennial), this plant has fall, but is also unattractive to deer and been overlooked for too long. Until recent- rodents because it is poisonous. The large ly, it was difficult to find it commercially, bulbs increase gratifyingly in a location but when the Georgia Gold Medal for where they are happy. They produce a lush Outstanding Garden Merit accorded it some crop of large, ribbed leaves early in the long-overdue recognition in 1996, the spring, which wither and disappear in the picture changed for this native of the cen - summer. Then in the fall, the plant produces tral and southeastern United States. The a cluster of pink, goblet-shaped first difference you’ll notice are the lobed flowers. More flowers appear for lower leaves (hence the name ‘triloba’). 1-2 weeks, so the display usually The flower stalk is also highly branched, lasts for 2-3 weeks. It is particu- giving the whole plant a much airier look larly effective when paired with than many coneflowers. The flowers are Scabiosa ‘Pink Mist’, as the two far smaller than other species, with shades of pink form a very satis- appealing little petals and a chubby, fying color echo. chocolate-purple eye. I find them to be nice cut flowers as well; they look partic- EUPATORIUM COELESTINUM Clockwise from top left: Eupatorium rugosium ularly good with purple New England / C ONOCLINUM ‘Chocolate’; Rudbeckia triloba; Rudbeckia nitida Asters, as well as , and are a COELESTINUM ‘Herbstonne’; Erigeron ‘Prosperity’. knockout with spires of Verbena bonar- Hardy ageratum is the common iensis punctuating the display. name for this species, and that is exactly what it resembles. The RUDBECKIA NITIDA ‘H ERBSTONNE’ habit is taller than that of most annual ageratums, but you can At 5-7 feet, this is not a plant for the faint of heart. prune the plant early in the summer to produce branching; left However, in a large border, it makes a spectacular anchor. The unpinched, plant height is approximately 24 inches. This species exact species of this is subject to debate; Allan should probably be considered a ground cover, as it is rhizomatous Armitage reports that it is probably a hybrid between R. and will wander through the garden. This habit can actually produce laciniata and R. nitida . It is a sturdy plant despite its height: In some serendipitous associations that turn out to be very attractive the face of our often violent thunderstorms, it remains upright — one of our plants stealthily inserted itself into a nearby edging of and strong. The flowers, a clear lemon yellow with a prominent sweet alyssum, a combination that is much nicer than either alone. green cone, are large and borne over an exceptionally long Eupatorium coelestinum is a native plant, untroubled by pests. It is bloom period. Stretching until well after Labor Day, this lofty available in violet and white. flower display helps fill the border. No major insect pests seem to bother it. Rabbits are interested in the young plants, EUPATORIUM RUGOSUM ‘CHOCOLATE’ so some protection may be useful in the spring. Another eupatorium that has been improved through breeding is Eupatorium rugosum. The culti - SCABIOSA COLUMBARIA var Chocolate, a selection of the older ‘Braunlaub’, ‘PINK M IST ’ has deep, bronzy-green leaves that pair well with This plant is one of the longest-blooming other plants, making it a valuable contrast plant in perennials in our display garden. The display the border. It has not proven to be totally hardy in starts in July and goes until very hard frosts. Michigan and is probably best considered a zone 6 Deadheading may increase the number of plant. I had it planted next to Gaura ‘Siskiyou Pink’ flowers, but the display continues whether or whose pink flowers, combined with the bronze not the blooms are removed. One of my foliage and white flowers of the eupatorium, made an favorite associations in the garden is Autumn outstanding association. It has also proven to be an Crocus Colchicum autumnale and this plant. excellent container plant. A short-day plant, The color echo is lovely, and the show contin- Chocolate is in its glory after Labor Day; a mature ues for several weeks. plant in bloom is absolutely drenched in flowers. SOLIDAGO RUGOSA ‘FIREWORKS’ ERIGERON ‘PROSPERITY’ I wish U.S. gardeners enjoyed goldenrod more. I This erigeron was a test item in the MSU am sure the aversion stems from deeply ingrained Perennial Trials for three years and performed beliefs that goldenrod causes hay fever (I even had a admirably, blooming all summer until frost. In our physician ask me about this once; he had always 2000 trials, the first flowers were produced May thought goldenrod was allergenic). However, with 31, and the plant was still in bloom October 4. The the breeding work being done in Europe, much bet- plant’s habit is mounding, and the flowers, borne in ter varieties have been developed. One such selec- loose clusters, are a rich violet with gold centers. It tion is Solidago rugosa ‘Fireworks’. This plant has is not palatable to Japanese Beetles, though it does spectacularly long-arched flower plumes that seem to get some light flecking each year from an remind one of exploding fireworks. While it does unseen insect pest on the foliage. Plants expand to travel a bit, it is much better behaved than its form a large continuous group but do not self-seed rampaging cousin. The graceful gold flowers look or spread by rhizomes. This is a great alternative to Top to bottom: Colchicum autumnale and Scabiosa very nice with ornamental grasses and red sedums. asters when customers are looking for summer Columbaria; Solidago rugosa ‘Fireworks’; Geranium No pests or diseases have affected it. through fall performance. ‘Rozanne’.

September 2001 GPN 59