A LUST FOR LAVENDER
I once attended a bridal shower in a most unusual home—one where everything was purple. I had never before seen such a commitment to decorating with a single color, and the effect was profound. The same concept actually works rather well in the garden, when balanced with a variety of shades from light to dark, along with touches of white, orange or chartreuse for punctuation. A horticulturist friend has designed landscape in gentle shades of lavender and celadon green—a most restful and serene retreat. Lavender is a natural color for many flowers, as well as the name of a favorite fragrant herb, and offers a wide selection of plants for an all-purple border.
The most vivid purple flower in the garden must be Petunia ‘Wave Purple.’ The classic electric purple form of this fast-growing, carpetforming annual has received the All America Selections (AAS) winner and now has a sister hybrid called ‘Wave Purple Improved.’ The ‘Wave’ series is great for landscaping, with disease resistance, heat tolerance and long flower production. Use in hanging baskets or as a groundcover for summer.
The old-fashioned, rosy-toned species cleomes (spider flowers) my grandmother grew reached head high and planted themselves wherever they wanted. They would spring up to fill any vacancy if she left them on their own. I still invite them into my garden, but there are newer, shorter, lavender choices like ‘Violet Queen’ and ‘Senorita Rosalita’ which are great to grow from seed. ‘Spirit Violetta’ and ‘Spirit Merlot’ are light and dark shades of spider being trialed at Kemper and worth checking out right now.
Julie is particularly fond of Gomphrena globosa ‘Buddy,’ with its tight, bright magenta, cone-like flowers. It sprawls and spreads to weave itself into floral knitwear with striking punctuation. She also likes cupflower (Nierembergia scoparia ‘Purple Robe’) which has—you guessed it—cup-shaped flowers in a wonderful blue violet. It is only about 8 inches high and spreading, so it is great for window boxes, edging and bedding. Isotoma axillaris, the Australian laurentia, is another tender perennial grown as an annual bedding plant here. The lavender to blue flowers continue all summer.
Native to Mexico and Texas, mealycup sage (Salvia farinacea) has long been a popular tender perennial that we grow as an annual. The variety ‘Victoria Blue’ is a gracious middle-of-the-border shrubby plant that may reach 3 feet in a good season. Another hot zone plant, the Mexican petunia (Ruellia brittoniana) is also a tender perennial grown as an annual in our climate. ‘Purple Showers’ is a more compact species, with mid-tone flowers that last only a day, but are borne in profusion, providing constant bloom until frost. One of the most heat tolerant plants I know is Verbena. The cultivar ‘Imaginatio’ has powerful blue-violet flower clusters on broad reaching feathery stems.
For foliage color, most gardeners rely on coleus. The varieties shift from year to year, but I am fond of ‘Trailing Plum Brocade,’ with dark purple leaves edged with a narrow border of shocking violet. ‘Gold Brocade’ is a shocking yellow gold with amethyst purple veins. My late summer florals depend on coleus as a colorful fill. Julie just loves Persian shield (Strobilanthes dyerianus) with vivid purple foliage highlighted with subtle silvery patches. In a happy place with a little late afternoon shelter, Persian shield may shrub up to 3 or 4 feet in a season. With great long stems, it is fabulous for cutting. Both coleus and Persian shield benefit from conditioning in tepid water for several hours to help them last well.
Filled with purple, yellow and white, the crocus lawn at the Missouri Botanical Garden is an awesome spring delight. In late spring, the giant globe alliums lining the front entry always make a strong purple statement, but I adore the smaller forms of flowering onion, too. My grandmother grew Allium senescens, the twisted onion, but it self-seeded all over the garden. There is a wellbehaved A. nutans cultivar, ‘Millennium,’ in the same foot-tall size range that doesn’t stray, with lots of 2-inch rosy lavender spheres, clusters of tiny individual flowers rising on slender stems. The Star of Persia, A. cristophii, offers more drama with striking mauve shooting-star flowers in broader, 8-inch umbels rising up on 18-inch stems. The visual impact lingers as the seed-heads dry to straw, still remarkable for texture even into the winter garden.
With many vegetables moving to the front border, it’s fun to have some handsome varieties to show off. While regular beets would fit into the purple plan with their deep mahogany veins and roots, there is a fancy maroon cultivar called ‘Bull’s Blood,’ a Plant of Merit (POM) that makes an outstanding dark, red-purple row. The roots, when sliced, show more color demarcation in the rings and are delicious when sliced for salads with very thin, raw slivers used in place of radishes. Another vivid foliage choice is Brassica oleracea ‘Redbor,’ a magnificent, deep, red-purple kale. It makes a knee-high color statement for the border or the salad plate and weaves well with sprawling, trailing bedders. My kale is one of the last soldiers standing in the December garden. Look for it now to include in your fall planting.
For beginning gardeners, ornamental hot peppers are easy-to-grow plants that offer both visual and culinary reward. Capsicum annuum ‘Black Pearl’ (POM) has been around for years, is reliable and offers striking color. The very dark, satiny purple-black leaves frame fruits that start green and pass through red as they ripen to a darker purple. The new variety Capsicum annuum ‘Purple Flash,’ a 2011 POM, has deliciously violet fruits on purple, slightly variegated foliage. Both peppers are good for the middle of the border or large containers. Caution: The fruits of both are edible but very hot.
Regular readers already know that Julie and I both adore a host of lavenders and purples with coneflowers, dianthus, irises, veronicas, hostas, Russian sage and hollyhocks among our special treasures. All of these have great selections with lavender or purple flowers.
For spring gardens, there is a lovely jewel-toned columbine called ‘Clementine Dark Purple’ that has deeply double powder-puff flowers. Lamium maculatum ‘Purple Dragon’ is a new archangel with silvered leaves and deep hued flowers. Put these along with catmint and you have a lovely seasonal combo.
The summer garden also boasts a great purple variety of bachelor’s button (Centaurea montana ‘Amethyst Dream’) with luscious, lacy deep maroon flowers. The daylily hybrid ‘Purple D’ Ora’ has bronzy red-purple tones overlaid on golden petals. There must be a million penstemons for the garden or in the wild. From a distance, they resemble the thin, delicate, open-faced snapdragons of which they are relatives. A great choice for our climate is Penstemon x mexicali ‘Pikes Peak Purple’ with regal purple petals and white-streaked throats. It is a recurrent bloomer, so if you cut for flowers, more will come.
Hardy geraniums are a great addition for low color in the summer border. I have several varieties, ranging in color from magenta to pale lavender blue. The English cultivar ‘Rozanne,’ with large violet-blue flowers, is a sterile hybrid that behaves well and blooms from early summer to frost. The common name cranesbill refers to the shape of the long seed pods.
A late summer into autumn garden special is the genus Aster. One of my longtime native favorites is New England aster, A. novaeangliae. It can shoot up shoulder-high floral sprays if it is in the right spot. A much more docile mound-forming cultivar is ‘Purple Dome.’ Much smaller is A. dumosus ‘Woods Purple,’ a grape-colored, mildew-resistant selection that stays under a foot and is suitable for containers or border planting. No fall garden is complete without asters. And my Peter chimed in with his recommendation of Callistephus, the purple Chinese aster.
Magnificent rich purple rhododendrons are great eye candy, but are a challenge to grow in St. Louis with our lime-laced soils. The ones at the Missouri Botanical Garden that look lush and bloom so well are supported by an acidifiedwater irrigation system, not a small investment for a garden. Heaths and heathers are also hard to grow here for the same pH reasons. Several popular purple garden plants are very invasive species and should be removed from our gardens. These include exotics like purple loosestrife, Lythrum salicaria, a federally listed noxious weed; the lovely but naughty tall verbena, Verbena bonariensis; and—you’ll hate me for this—our favorite purple butterfly bush, Buddleia. All of these exotics get seriously out of bounds in some regions of the U.S. and contribute to pressures on our rare and endangered native flora.
Visit the Missouri Botanical Garden website, mobot.org/gardeninghelp, for more selections.