Curio repens
Family: Asteraceae​
Synonym: Kleinia repens, Senecio serpens
​Common Name: blue chalk sticks, snake ragwort
Origin: Curio repens is endemic to the Western Cape of South Africa, however it has been introduced and is widespread in New Zealand (1).
Description: Curio repens is a sprawling succulent shrub that has a creeping habit (1). This plant can grow to heights of 6-8 inches and spreads up to 3 feet, with roots forming at each stem node as they touch the ground (3,4,5,6). Leaves are 1-2 inch long, and slender with a silvery blue-green hue (6). Its cylindrical leaves are fleshy and angled upwards like blue-grey tapered candles (6). This plant develops discoid flowers (groups of disk flowers) organized into an inflorescence called a corymb, with each head in the corymb being a compound flower comprised of many tiny white disk flowers (5,7,8). When successfully pollinated, the flowers produce a dry dehiscent fruit that splits to release the seeds, each of which have a feathery white pappus to facilitate wind dispersal (3).
 
Interesting Features:
  • Curio repens is designated as a fire-resistant plant, making it a strategic addition to landscapes in areas with high risk of wildfire, and it is also popular for its ability to tolerate salty soils (3,5,10).
  • Uses:  Curio repens is solely used for ornamental purposes, however due to its toxicity, care should be taken to keep it out of reach from children and pets (6,7). This plant is commonly used as a ground cover, due to its thick, mat-like growing habit (4,6,7). It is often chosen for its versatility and ability to stylistically blend well within both southwestern or Mediterranean themed gardens, as well as its addition as a striking silver blue accent color (4).

Cultivation and Care:
  • Watering: Low
    • Although this plant is considered low water use, a frequent watering schedule may be needed during the hottest part of summer, with very infrequent watering in the winter.
    • Avoid overwatering and allow the soil medium to dry out between waterings.​
  • ​Soil: This plant prefers sandy soil with good drainage, a potting medium formulated for succulents would be suitable (4,5,6).
  • Lighting: This plant prefers full sun to thrive, however it can tolerate part-shade and may actually benefit from part-shade in very intense heat (4,6,8).
  • Propagation:  This plant can be propagated by seed, however propagation vegetatively is more effective (3,8)
  • Cold Tolerance: 30°F, USDA hardiness zones 9b and greater. Intolerant of frost, protection from exposure is needed.
  • Special Accommodations: This plant is often afflicted by pests, including aphids, spider mites, and white flies (8). These problems are less troubling when grown in suitable conditions.
    • It generally does not require pruning, however removing the shoot tips can promote denser, more branched growth (8).

Sources:
  1. Curio repens (L.) P. V. Heath articles - Encyclopedia of Life (eol.org)
  2. Curio repens (L.) P.V.Heath | Plants of the World Online | Kew Science
  3. Blue Chalksticks (Curio repens) - Garden.org
  4. Blue chalksticks - Inland Valley Garden Planner
  5. Curio repens (Blue Chalksticks) - World of Succulents
  6. Senecio groundcovers – PlantRight
  7. Senecio serpens - How to grow & care (growplants.org)
  8. Senecio Serpens — SLO Botanical Garden (slobg.org)
  9. Leon, G. (April 1st, 2021). Plant: House plants: choosing, styling, caring. Octopus.
  10. Senecio serpens (botanicgardens.sa.gov.au)​