Helichrysum petiolare

licorice plant

Ratings

This plant has a Plant Risk Evaluator rating of High Potential Risk
This plant has been rated Limited by the California Invasive Plant Council

Description

Licorice plant comes from the drier locations in the Cape of South Africa. It is a clambering shrub that will creep up anything that gives it support up to 30 ft. tall or will grow unsupported to form a shrub 6 ft. tall by 10 ft. wide. It has aromatic woolly, silver-white leaves. It reproduces by seed and can also grow vegetatively from stem fragments. The naturalized populations do not appear to be spreading very rapidly. CalWeedMapper shows its current distribution in California outside of cultivation.

Several cultivars exist with different colored leaves. 'Limelight' has chartreuse to yellow leaves. 'Lemon Licorice' yellow-green leaves, and 'Licorice Splash' has variegated green and green-yellow leaves.

This plant has done a bit too well in the San Francisco Bay area, and has displaced native plants in the Golden Gate National Recreation Area and other sensitive coastal habitats. For that reason, San Marcos Growers discontinued selling this plant. 'Limelight' rarely flowers. More research on cultivars of Helichrysum petiolare is needed to determine if they are safe to use as alternatives to the parent species.

Why is this plant not included on the invasive plant list?

Licorice plant was considered for addition to the plant list from 2012-2014, and was included in the 2017 nursery survey. Including this plant in the survey as well as Plecostachys serpyllifolia helped us find occurrences of P. serpyllifolia that were likely not recorded last year because P. serpyllifolia is often sold as Helichrysum petiolare 'Petite Licorice'.

During the 2017 nursery survey, Helichrysum petiolare was found at 9.3% of nurseries. A few cultivars were found, including 'Limelight', 'Lemon Licorice', 'Licorice White', and 'Licorice Splash'. The invasive potential of these cultivars relative to the parent species is unclear. Also, Helichrysum petiolare has become invasive primarily in the San Francisco Bay Area and on Santa Cruz Island, and not really anywhere else in California. Based on these factors, we decided that it did not warrant addition to the plant list and being a Plant to Watch is sufficient for now.