Brunnera macrophylla goes by several equally prevalent common names, including Siberian bugloss, false forget-me-not, brunnera, large-leaf brunnera, and heartleaf. Whatever you call it, this species has always been a popular shade plant because it has long-lasting sprays of bright blue flowers and because it is so low maintenance.
This clumping perennial spreads from rhizomatous roots and has dark-green heart-shaped leaves. Small blue flowers with white centers rise on stems in spring; the bloom period lasts for about four weeks. Although Siberian bugloss is a slow grower, the green-leaved species will eventually spread out and make a nice ground cover. The flashier variegated varieties are a bit slower to fill out, but provide interest and color all season.
The common name "bugloss" is derived from the Greek words for "ox" and "tongue", as the leaves are thought to resemble an ox tongue. It's easier to see how it got its other common name, "false forget-me-not": The blue flowers may have you doing a double-take with their resemblance to the blooms of the real forget-me-not (Myosotis scorpioides).
Siberian bugloss is generally planted from potted nursery plants in early spring, as soon as the ground can be worked. It grows rather slowly, which is an advantage since it doesn't demand frequent division and rarely becomes invasive.
|Botanical Name||Brunnera macrophylla|
|Common Names||Siberian bugloss, brunnera, large-leaf brunnera, heartleaf, false forget-me-not|
|Plant Type||Herbaceous perennial|
|Mature Size||12 to 18 inches; 18- to 30-inch spread|
|Sun Exposure||Part shade to full shade|
|Soil Type||Medium moisture, well-drained soil|
|Soil pH||No preference|
|Bloom Time||April to May|
|Hardiness Zones||3 to 8 (USDA)|
|Native Area||Caucasus region of Eurasia|
How to Grow Siberian Bugloss
Siberian bugloss is best planted in a part-shade to full-shade location in a good rich soil that has excellent drainage. In a good environment, this is a largely care-free plant that requires little more than division every three or four years.
Since Siberian bugloss prefers cool, moist shade, slugs may become a problem, but varieties with thicker leaves are rarely bothered.
Siberian bugloss prefers shady conditions, though it can survive in full sun if it gets more moisture. But the variegated leaves can easily burn in direct sunlight and plants may go dormant in extremely sunny conditions.
This plant is not particular about soil pH, but it does like rich, moist soil. Lots of organic matter and organic mulch will help it become established quickly and keep it growing well. This plant does not tolerate dry soils.
Keep new plants well watered. While Siberian bugloss plants prefer constant moisture, they will become more drought tolerant once they are established. Mulching will help maintain the cool, moist soil that Brunnera prefers.
Temperature and Humidity
Though rated for zones 3 to 8, Siberian bugloss prefers regions with cool summers. You may have trouble with it in zones that have especially hot and humid summer conditions (zones 7 to 8).
These plants prefer rich soil but do not require supplemental feeding, as long as the soil is not too poor or dry.
Propagating Siberian Bugloss
The best means of propagation is to simply dig up an established clump in early spring, divide it into healthy segments, and replant. Siberian bugloss can be short-lived, and dividing your plants every three to five years will keep them around longer.
Although the named cultivars may self-seed, the volunteers usually do not grow true to the parent plant and are best weeded out if you want to preserve the look of the parent. For example, volunteer seedlings of variegated plants often have solid green leaves.
The older leaves may start to get tattered and can be cut back during the growing season to encourage new leaves to fill in. Don't cut the whole plant back to the ground in the fall—the leaves will help protect the crown during winter and you can easily clean away the old foliage in the spring when the new leaves begin to emerge.
If you do not want your plants to self-seed, deadhead as the flowers start to fade. If you would like to collect the seed to sow, allow the flowers to dry slightly, then cut and let then finish drying in a paper bag. The seeds will fall off as the flowers dry.
Growing in Containers
This plant can be a great choice for containers. The variegated leaf varieties will make a nice filler throughout the season. Many are hardy enough to remain in containers throughout the winter, with a little extra protection.
Varieties of Siberian Bugloss
The species form of B.macrophylla, with solid green leaves, is readily available. It has lovely sprays of blue flowers and is an extremely tough plant. In addition, there are several cultivars available, including:
- 'Diane's Gold' has golden-yellow leaves and blue flowers.
- 'Hadspen Cream' has extra-large leaves with irregular white outer margins.
- 'Jack Frost' has silvery leaves with green veins.
- 'Langtrees' (aka 'Silver Spot') is a very hardy plant with leaves that are dotted with silver.
- 'Looking Glass' has silver leaves that look almost metallic.
Use Siberian bugloss in shade gardens, woodland settings, and near ponds. It can make a great ground cover and looks beautiful lining a path or border, although it can take a while to fill in.
Since deer do not often bother this plant, it makes a nice alternative to hostas. Companions with different textures and leaf shapes include hellebores, iris, hostas, bleeding heart, geraniums, and even late-blooming daffodils.