LITHODORA
At this time of the year, it is hard to curb your enthusiasm. While trolling the local garden centers for interesting pansies and violas, I was nearly overcome by the sight of all the freshly-delivered perennials, annuals, trees and shrubs. If I were either Warren Buffett or a Power Ball Lottery winner, I would have cut to the chase and just made an offer for the entire inventory of my favorite plant emporium. Of course that would have left me with an unconscionable amount of dusty miller, but I am sure I would have found a way to use it.
Plants with true blue–not blue-purple–flowers are among the most desirable and rare in the garden. Members of the borage or Boraginaceae family often boast these true blue blooms. In addition to the herb borage, for which the genus is named, family members include forget-me-not or Myosotis, lungwort, known botanically as Pulmonaria; and bluebells or Mertensia. The flowers are not always large, but they are usually an eye-catching shade of blue.
While staggering through the garden center with flats of early spring annuals, I came face to face with a beautiful borage relative–Lithodora. The flowers reminded me of very large forget-me nots and the small leaves made me think of rosemary or thyme. The plant was a low grower and bore a tag claiming that it would reach no more than twelve inches tall, with a potential spread of up to six feet. Since I have been desperately seeking good groundcovers, I snatched it up.
My new plant is more formally known as Lithodora diffusa ‘Grace Ward’. Its shrubby genus, Lithodora, contains seven species, all native to Eastern Europe. Of those seven, only diffusa is commonly cultivated. In addition to ‘Grace Ward’, there is cultivar called ‘Heavenly Blue’ and another, sold as ‘White Star’. ‘Heavenly Blue’ has an even deeper color than ‘Grace Ward’; while ‘White Star’ is blue with white markings. All three varieties have similar dimensions and cultural requirements.
As is often the case, the Latin name tells a lot about the plant. “Litho” is the Latin word meaning “stone.” Generally plants with “litho” in the name are low-growers that thrive in crevices between stones. They are good rock garden specimens and like the kind of well-drained soil found in alpine situations. Lithodora fills this bill perfectly.
“Odora” is generally associated with fragrance, but the leaves of my ‘Grace Ward’ do not have any discernable scent. Perhaps the species’ foliage is more fragrant.
“Diffusa” signifies that the plant is loosely branched. In the case of Lithodora diffusa, the loose, branching habit is what enables it to spread nimbly along the ground.
The only thing the Latin name does not tell you is whether the plant needs sun or shade. The answer is “sun,” though in southern climates, it may thrive better with a little afternoon shade.
My research suggests that lithodora is easy to grow, but has one potential problem. As it spreads, the plant’s growth can become sparse in the middle. You can disguise this sparseness by planting new lithodora plugs in the bare spots or by combining lithodora with other ground covers. Ajuga, with its blue purple flowers and mat-forming habit would be a nice companion. By choosing a variety of groundcovers that contrast in color and texture, you can fill a large area with a tapestry-like array of plants.
Lithodora blooms in the summer, giving you something to look forward to after the riot of spring flowers is over. It is also, reputedly, deer and critter resistant. I always take such claims with a large grain of salt, but if deer or other varmints are a problem where you live, you might want to try a plant or two and see what happens.
Groundcovers of all kinds are very fashionable, from little mosses to larger species like big leaf geranium. Lawns overall are shrinking and people want low-growing plants that are like perfect spouses–good looking and easy to care for. Lithodora is an ideal choice, as long as no one wants to walk on it.
My ‘Grace Ward’ lithodora was marketed by Monrovia, one of the biggest plant wholesalers and brand leaders in the horticultural world. This means that the plants should be available in large and small nurseries and garden centers this spring. Buy ‘Heavenly Blue’ from White Flower Farm, P.O. Box 50, Route 63, Litchfield, Connecticut 06759;(800) 503-9624; www/whiteflowerfarm.com. Fre