Crassula muscosa aka Watch Chain

Crassula muscosa is a compact succulent subshrub that typically reaches 25-40cm (10-16 inches) in height with a spread of about 20cm (8 inches). It has a slow growth rate and develops slender, branching stems densely covered with tiny scale-like leaves arranged in four rows, creating a distinctive zipper or watch chain appearance. The stems can be erect to decumbent (trailing) and become slightly woody at the base over time.

Crassula muscosa thrives in temperatures between 60-75°F (15-24°C) with an ideal range around 68-70°F (20-21°C). It is not cold hardy and should not be exposed to temperatures below 50°F (10°C) in winter. In USDA zones 9-11, it can grow outdoors year-round, but in colder climates, it must be kept indoors or protected from frost. Sudden temperature fluctuations should be avoided.

Crassula muscosa produces tiny, pale yellow-green flowers that appear along the stems between the leaves during spring to mid-summer. The miniature five-petalled blooms are easily overlooked due to their small size and start off white before turning brownish as they age. When grown indoors, flowering is less common as the plant needs adequate bright light to trigger blooms. The flowers have a distinctive musty, soapy scent.

The flowers of Crassula muscosa produce a distinctive musty, soapy fragrance that is quite unusual and difficult to compare to other scents. This scent is only noticeable during the blooming period in spring to mid-summer when the tiny yellow-green flowers appear. The foliage itself does not have a noticeable scent.

Several varieties of Crassula muscosa are recognized: var. muscosa (the typical form), var. obtusifolia (with blunter leaves), var. parvula (a smaller form), and var. polpodacea. There is also a popular variegated form (C. lycopodioides var. variegata) with silver-grey foliage, and a fascinating crested form (f. cristata) that develops fan-shaped growth. The species shows natural variation across its native range in South Africa and Namibia.

Crassula muscosa can grow outdoors year-round in USDA hardiness zones 9-11, where temperatures stay above 20°F (-6.7°C). It performs well in partial shade locations and should be protected from intense afternoon sun which can scorch the foliage. The plant has naturalized in Mediterranean climates including parts of Spain, France, Italy, and the Canary Islands. In colder regions, it can be grown outdoors during summer but must be brought inside before frost.

Crassula muscosa propagates easily from stem cuttings. Cut a 2-5cm stem section using a sterile knife, allow the cut end to callous for 1-2 days, then place in clean river sand or well-draining succulent soil. Mist every 3-4 days and roots should develop within 2-3 weeks. The best time to propagate is during spring and summer when the plant is actively growing. A stable temperature of 68-70°F (20-21°C) promotes rapid rooting. While leaf propagation is possible, it is slower and less reliable than stem cuttings.

Crassula muscosa benefits from occasional pruning to maintain its shape and encourage bushier growth. After several years, the plant can become untidy and leggy, at which point it is best to cut back the stems or start fresh from cuttings. Remove any dead or damaged stems as needed. Pruning is best done in spring during active growth. The removed stem cuttings can be used for propagation.

Crassula muscosa has a shallow, fibrous root system and does well in shallow pots. Repot every 2-3 years or when the plant outgrows its container. Use a pot with drainage holes and fresh well-draining succulent or cactus soil mix. Clay pots are ideal as they help excess moisture evaporate. The best time to repot is in spring at the start of the growing season. Avoid overwatering after repotting to prevent root rot.

Due to the densely packed, tiny leaves along its stems, Crassula muscosa can trap dust and debris. Gently rinse the plant under lukewarm water to remove dust, or use a soft brush to clean between the leaves. Avoid using leaf shine products which can clog the stomata. Regular cleaning also helps prevent pest infestations by removing hiding spots for mealybugs and other insects. Allow the plant to dry thoroughly after cleaning.

Crassula muscosa is susceptible to mealybugs, which appear as white cottony masses in leaf joints and around the crown. Aphids and scale insects can also occur. Treat infestations with neem oil mixed with horticultural soap, applied weekly for 6 weeks. The dense leaf structure provides hiding spots for pests, so regular inspection is important. Root rot and fungal diseases occur from overwatering and poor drainage. If root rot develops, take healthy cuttings and restart the plant in fresh soil.

Yellow leaves on Crassula muscosa typically indicate overwatering, which is the most common care mistake with this drought-tolerant succulent. Allow the soil to dry completely between waterings and ensure the pot has adequate drainage. Poor ventilation and humid conditions can exacerbate the problem. If the stem base feels mushy along with yellowing, root rot may have developed. In this case, take healthy cuttings from unaffected parts and repot in fresh, dry soil.

Brown leaves on Crassula muscosa can result from several causes. Sunburn from too much direct sunlight causes brown, scorched patches. Underwatering leads to brown, wrinkled, shriveled leaves. Fungal diseases including powdery mildew can also cause browning. Check light exposure and watering habits first. If browning is extensive, remove affected parts and adjust care accordingly. Deep shade can also cause problems - LLIFLE notes plants get 'weak and leggy and eventually rot' without sufficient light.

Drooping or wilting in Crassula muscosa is usually caused by either underwatering or root rot from overwatering. Check the soil moisture - if bone dry and the plant is wrinkled, water thoroughly. If the soil is wet and stems feel mushy, root rot has likely set in due to overwatering. In the case of root rot, remove the plant, trim away affected roots, allow to dry, and repot in fresh dry soil. Excessive direct sunlight can also cause temporary wilting.

Crassula muscosa is naturally a slow-growing plant, so some patience is needed. However, extremely slow or stalled growth may indicate insufficient light - the plant needs bright indirect light for at least 6 hours daily. Growing in deep shade causes weak, leggy growth and can lead to rot. Nutrient deficiency during the growing season may also slow growth. Apply a diluted liquid cactus fertilizer monthly during spring and summer. Check that the plant isn't rootbound and repot if needed.

Crassula muscosa is native to southern Africa, specifically the Cape Provinces, Free State, and Northern Cape of South Africa, as well as Namaqualand and southern Namibia. It grows in semi-arid and arid karoo regions, particularly in rocky habitats. The species has since naturalized in Mediterranean climates including the Canary Islands, Corsica, France, Italy, Spain, and Tasmania, demonstrating its adaptability to similar dry, warm conditions.