Crassula perfoliata aka Red Treasure

Crassula perfoliata is an easy-to-grow succulent that tolerates neglect and is well-suited for beginners. It requires minimal watering, thrives in sunny positions with well-drained soil, and has few pest problems. As long as you avoid overwatering — the primary cause of failure with this plant — it will reward you with striking architectural foliage and, in mature specimens, clusters of colourful summer flowers.

Crassula perfoliata prefers warm conditions and should be protected from frost. It can tolerate brief cold snaps down to about −5°C (23°F) if the soil is kept completely dry, but prolonged freezing will damage or kill the plant. In its native South African habitat, average daily temperatures range from about 10°C (50°F) at night to 25°C (77°F) during the day. Indoors, normal room temperatures are fine, but avoid placing it near cold drafts or heating vents.

Crassula perfoliata is a slow-growing succulent subshrub that takes 5–10 years to reach its full size. The species is variable depending on the variety: var. perfoliata can reach up to 1.3 metres tall, var. falcata grows 0.5–1 metre tall and about as wide, and var. minor stays more compact at around 0.5 metres. The growth habit is erect and sparingly branched, with thick, fleshy leaves arranged in striking opposite pairs along the stems.

Crassula perfoliata can be propagated by leaf cuttings, stem cuttings, division, or seed. Stem cuttings are the fastest method for a decent-sized plant — take a cutting and allow the cut end to callus over for a few days before inserting into well-drained sandy soil. Leaf cuttings are the easiest method: simply lay a healthy leaf on moist sand in spring or summer. Seeds can be sown in spring at 15–18°C and typically germinate within three weeks, though seed-grown plants may take four years to flower. Apply a fungicide such as sulphur powder to any cut surfaces to prevent rot.

Yes, Crassula perfoliata produces clusters of flowers in summer. The flower colour varies by variety: var. perfoliata has small white blooms, var. falcata produces spectacular dense cymes of bright scarlet-red to orange-red florets in heads 8–12 cm across, and var. coccinea has deep red flowers. The flowers of var. falcata are sweetly fragrant with a cinnamon-like scent and typically last 6–8 weeks, attracting butterfly pollinators. Seed-grown plants may take up to four years to produce their first flowers.

The flowers of Crassula perfoliata var. falcata are sweetly fragrant with a distinctive cinnamon-like scent. This fragrance is quite noticeable when the plant is in full bloom during summer and typically lasts for 6–8 weeks. The scent attracts butterfly pollinators. Other varieties (var. perfoliata, var. coccinea) are described as having sweet-scented flowers but are less strongly fragrant.

Crassula perfoliata has four recognized varieties. Var. perfoliata is the type variety, growing to 1.3m with lanceolate leaves and white flowers. Var. falcata (the Airplane Plant) is the most popular in cultivation, recognised by its grey-teal sickle-shaped leaves and brilliant scarlet flower clusters — it holds the RHS Award of Garden Merit. Var. coccinea has deep red flowers and erect, channelled leaves. Var. heterotricha is a smaller form at about 40 cm. Notable hybrids include 'Buddha's Temple' (× C. pyramidalis) and 'Morgan's Beauty' (× C. mesembryanthemopsis).

Crassula perfoliata grows well outdoors in USDA zones 9b–11b, where minimum winter temperatures stay above about −4°C (25°F). It's excellent in rockeries, succulent borders, and dry garden beds, preferring a spot with full sun and well-drained soil. In cooler climates, grow it in containers that can be moved indoors for winter. It can survive brief frosts down to −5°C if kept very dry, but prolonged cold or wet winter conditions will be fatal.

Yes, care should change with the seasons. In spring and summer (the active growing season), water moderately using the soak-and-dry method and feed monthly with a diluted balanced fertiliser. This is also the best time for repotting and taking cuttings. In autumn, gradually reduce watering. During winter dormancy, water sparingly — just enough to prevent the leaves from shrivelling — and stop fertilising entirely. If growing outdoors in borderline climates, bring potted plants indoors before the first frost.

Repot Crassula perfoliata in spring at the beginning of the active growing season, and only when the plant has outgrown its current container. Make sure the soil is completely dry before repotting, then wait a week before watering the newly repotted plant to allow any damaged roots to heal. Use a well-draining succulent or cactus mix, and choose a pot with drainage holes — terracotta or unglazed clay pots are ideal as they allow excess moisture to evaporate.

Crassula perfoliata requires no regular pruning. The RHS confirms 'no pruning required' for this species. You can remove spent flower stalks after blooming to keep the plant tidy, and trim any dead or damaged leaves as needed. If the plant becomes leggy or top-heavy, you can cut back stems to encourage bushier growth — the cuttings can be used for propagation.

Crassula perfoliata is generally disease-free but susceptible to a few common pests. Mealybugs are the most frequent problem, appearing as white cottony masses in leaf axils and on stems. Vine weevil and aphids can also be an issue. Overwatering is the primary cause of disease, leading to root rot and fungal infections. Ensure good air circulation and well-drained soil to prevent these problems. Treat mealybug infestations with rubbing alcohol applied directly to affected areas or with an appropriate insecticidal soap.

Crassula perfoliata is endemic to southern Africa, distributed across South Africa (primarily the Eastern Cape, but also KwaZulu-Natal, Cape Provinces, and Northern Provinces), Eswatini, Mozambique, and Zimbabwe. It grows mainly on dry, partially exposed lower slopes and canyon walls, confined to outcrops of quartzitic sandstone at altitudes of 250–1,000 metres. Its natural habitats include Fynbos and Albany Thicket biomes, where it typically occurs on rocky cliff exposures along dry river valleys.

Yellow leaves on Crassula perfoliata are most commonly caused by overwatering, which leads to root rot and prevents the roots from absorbing nutrients. Check that the soil is drying completely between waterings and that the pot has adequate drainage. Other causes include insufficient light (the plant needs at least 6 hours of direct sun), nutrient deficiency from exhausted soil, or natural ageing of lower leaves. If the stems feel mushy or the soil smells sour, root rot is likely — unpot the plant, remove any rotten roots, let it dry, and repot in fresh dry succulent mix.

Crassula perfoliata is primarily pollinated by insects, particularly butterflies. The fragrant flowers (especially the cinnamon-scented blooms of var. falcata) attract these pollinators during the summer flowering period. After pollination, the plant produces tiny seeds that are dispersed by wind. The species can also be hand-pollinated for seed production, though vegetative propagation via leaf or stem cuttings is far more practical for most growers.

Red Treasure does best in dry soil and should only be watered sparingly.

To ensure the health of your Red Treasure, it's crucial to use a potting soil that won't hold too much moisture. A soil that drains well and contains perlite or vermiculite for drainage and organic matter for nutrition is ideal. Adding a few handfuls of perlite to store-bought cactus soil is an easy way to create this type of soil mix.

Red Treasure thrives in bright and direct sunlight. To ensure your plant receives enough light to survive, place it less than one foot from a window. The current weather in your area may affect the placement in your home. For example, if you live in a region that has longer and more intense periods of sunlight, then you may want to place the plant farther away from the window to avoid direct sunlight and reduce the risk of sunburn. Alternatively, if you live in a region with relatively milder temperatures and less intense sunlight, then you may be able to place the plant closer to the window for increased exposure. Ultimately, the current weather in your area should be taken into consideration when determining the best placement for your Airplane Plant.

Red Treasure prefers dry environments, so misting the plant to provide extra humidity and allow water to linger on the leaves can create an ideal environment for fungi that can be harmful.

The growth rate of Red Treasure is slow and it doesn't necessitate additional fertilizing. By changing the soil in its pot annually, the plant should be provided with adequate nutrition. It is crucial to keep in mind that plants derive their energy from the sun, not fertilizers.

The toxicity level of this plant has not been officially confirmed by Ploi. If there is a possibility of ingestion of plant material with an uncertain toxicity by you, a family member, or a pet, it is advisable to seek the assistance of a medical professional.