Jeff Green | Mar 27, 2008
Master Gardeners - March 27, 2008
Back toHomeMaster Gardeners - March 27, 2008 Sneaking a peek at summer-long perennials Kathleen Lang, Lanark County Master Gardeners
Many gardeners have commented that the only thing that they have against perennials is that each one blooms only at a certain time and one must have such a grand variety of plants to have blooms all summer. In this column, I would like to profile a couple of plants that will give you pleasure all summer long, both with their lovely foliage and long bloom times.
Alchemilla mollis, or Lady's Mantle, is a plant that no garden should be without. The name is derived from the shape of the leaves, which are roughly circular with a wavy, toothed edge and veins, forming deep folds or pleats. The leaves are also hairy and this quality, plus the folds, often causes them to hold quicksilver droplets of water, which make them such an admirable target for photographers. The light green leaves are topped by froths of yellowish-green flowers. Lady’s Mantle is equally at home in formal plantings or a wild garden and combines well with a variety of colors. The flowers have a curious aromatic fragrance which is quite pleasant and it makes an excellent cut flower, especially with blue sweet peas.
This plant is at home in either sun or shade. It will grow in any ordinary soil; however, in hot, dry climates it prefers an adequate moisture supply. It is attractive when used as an edging plant, in the border, rock garden or as a groundcover or pond accent.
Heuchera "Palace Purple' is a stunning addition to most any landscape. The most striking feature of 'Palace Purple' is its reddish-bronze foliage which, on a sunny day, grabs your attention from across the yard. Foliage height is usually not more than 12 inches, but when the plant produces sprays of small, off-white flowers in summer, expect those to stand about 18 inches tall. Heuchera is an adaptable plant that performs well in our area in a variety of soil types, although it will not thrive in heavy clay. The addition of generous amounts of organic matter to any soil is an important step to growing top-quality specimens. In areas with long, hot, humid summers, this plant needs some degree of protection from the sun. Most desirable would be afternoon shade when the sun's rays are most intense.
Perovskia atriplicifolia, commonly known as Russian Sage, grows best in sunny dry locations and is one of the most heat resistant and drought resistant perennials available. It has silver stems and small, greyish foliage and small light blue to lavender flowers that are arranged in whorls along the stem. The spikes are often 12 inches or longer. Perovskia begins flowering in July and often continues well into September or even October. It is easily grown in our hardiness zone. In shaded areas the plant will grow, but tends to be leggy and sprawling. The only condition that Perovskia resents is poor drainage, especially in winter. For best results plants should be cut back nearly to the ground each spring before new growth begins.
In the garden, Perovskia's bright blue flowers are particularly striking when planted with white flowering species such as Phlox paniculata 'David' or 'Mt Fuji'. Perovskia also makes a pleasant cut flower. Other uses include massing in the border as welI as separating two very dominant colors.
For those who have very shady gardens or who are blessed with a woody segment to their property, ferns offer color, texture and variety. Adiantum pedatum (Northern Maidenhair Fern) is very hardy. Its fan-shaped airy fronds change from light green in spring to gold in fall.
Another delightful fern for your collection is Athyrium niponicum 'Pictum; (Japanese painted fern.) This plant offers an exotic coloration: stems pink to burgundy, green to grey fronds with blue and pink highlights. It is very hardy and best placed close up, so its color variations can be best observed.
Coreopsis 'Moonbeam' is one of the most easily grown and longest blooming perennials. The clumps impart a very fine textured clump covered in creamy yellow daisy-like flowers throughout the summer and into the fall. Well-drained soils are the key to success, so heavy clay soils need to be amended with very generous amounts of organic matter. 'Moonbeam' is fairly drought-tolerant. For the maximum amount of bloom and the most attractive growth habit, plant in full sun. East-facing locations also give good results.
Veronica 'Sunny Border Blue' is a lovely plant valued for its ease of growth and long bloom season. It has luxurious, dark green rounded leaves and dark violet-blue flowers that are borne in erect spikes up to 18-24 inches tall.
Besides making a fine show in any border, it is also a highly prized cut flower. 'Sunny Border Blue' will bloom throughout the summer and into early fall. Although it will tolerate very light shade, the best results are obtained in full sun. This Veronica combines well with a number of garden perennials and looks especially pleasing with white, pink or yellow-flowered plants.
For more gardening information, phone Kathleen Lang at 613-283-5982.