The licorice plant (Helichrysum petiolare) has been enthusiastically embraced by gardeners for its frosted, felt-like leaves and its gently spreading growth habit. Although not large, the licorice plant makes a strong impact with its unique texture, form, and color, and makes a great groundcover or trailing plant for containers. It gets the name "licorice" plant because many varieties have a licorice scent, although the plants are not edible and are not used for making licorice. The species is listed as invasive in some areas where it is perennial.
- Botanical Name: Helichrysum petiolare
- Common Names: Licorice Plant, Liquorice Plant, Silver Bush, Trailing Dusty Miller
- Plant Type: Perennial
- Soil Type: Most well-drained soils
- pH: Any
- Light Exposure: Sun to partial shade
- Hardiness Zones: 9–11
- Mature Size: 12–18 inches high, 24–36 inches wide
- Leaves: The small, roundish leaves are covered in soft, gray hairs, giving them both a velvety or felt-like feel and an iridescent look. Although they are most commonly found in shades of silver and gray, there are newer cultivars that offer golden and white options. The leaves give off a subtle licorice scent, but no flavor.
- Flowers: The flowers are small and insignificant. In areas where it is grown as an annual, the plants will probably not flower at all. Licorice Plant is grown specifically for its foliage.
The licorice plant is a tropical perennial and is only hardy in USDA Zones 9 – 11. However, they are easily grown as annuals, elsewhere. Licorice Plant also makes a nice houseplant, if you can give it plenty of light.
A full sun site is best for growing the licorice plant. However, since they are not grown for their flowers, they will also do well in partial shade. The plants will be a little less vigorous in partial shade, but in areas with excessive heat, the leaves may stay more attractive when they are given some relief from the hot sun.
The licorice plant is a mounding plant that creeps or trails. Expect it to reach a mature size of about 12–18 inches (30–45 centimeters) high and 24–36 inches (60–90 cm) wide.
If grown as an annual plant, do not expect to see any flowers. Even where it is perennial, the flowers are so small and insignificant; you may not notice them. If you like, you can cut or prune them back to keep the plant's energy going into the leaves.
Licorice Plant Growing Tips
Soil: The licorice plant will grow in most soil, but it can develop root rot in soils that retain water, so a well-draining site or container is best. It is not particular about soil pH.
Starting from Seed: You may be able to find the seed of the species (Helichrysum petiolare), but most other cultivars will need to be propagated from stem cuttings. You can also purchase plants as seedlings, in containers, and sometimes as houseplants.
Planting: Licorice plants cannot handle any frost. In general, wait until it is warm enough to plant tomatoes and peppers, before putting your licorice plant outdoors.
Caring for Licorice Plant
Water: The licorice plant is very drought tolerant, but it grows best with regular watering. Make sure the excess water drains and the plants are not sitting in wet soil, or the roots will rot. It is time to water again when the top 1 -2 inches of soil are dry.
Fertilizer: Licorice plants are not heavy feeders. If your soil is poor, add some compost or other organic materials. This will add some trace nutrients as well as improve drainage.
When grown as an annual, you can also apply a balanced fertilizer mid-season, for an extra boost. If your plants are perennial, a dose of fertilizer once or twice a year may be needed.
Caring for Licorice Plants
The licorice plant is drought tolerant, once it becomes established. It is easier to kill with too much water than with too little, but regular water is still necessary. Just make certain the water is allowed to drain, not puddle.
You may want to do cut back some of the older licorice plant stems, as they start to brown, just to keep the plants attractive. You can also pinch back the stems if you want a fuller or smaller plant.
Pests and Problems
As with most fuzzy-leaved plants, the licorice plant is virtually pest and disease free. Even deer avoid it. The most common problem is rotting if the soil becomes too wet. The leaves can also become scorched if the plants are grown in hot, direct sun and not given enough water.
Licorice plants add softness to combinations and blend especially well with pastel flowers. The licorice plant can be used along edges, in containers, or as an underplanting. Licorice plants make a nice filler under roses or other leggy shrubs.
New cultivars of licorice plants are slowly starting to be introduced to the market, and new varieties often push the older varieties out of cultivation. Often, there are only subtle differences, as they are all bred for the color of their leaves.
- Helichrysum petiolare: The species is a very elegant silver-gray that complements other colors.
- Limelight: Not as fast a grower as the species, with chartreuse colored leaves.
- White Licorice: A cultivar with a more pronounced frosted effect.