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.
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.
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. 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.
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.
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.
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.
Temperature and Humidity
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.
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.
Varieties of Licorice Plants
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: A very elegant silver-gray that complements other colorsLimelight: Not as fast a grower as the species, with chartreuse-colored leavesWhite Licorice: A cultivar with a more pronounced frosted effect
Growing From Seeds
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.
Common 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.
Design Tips
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.
