Crassula tetragona aka Miniature Pine Tree

Crassula tetragona typically reaches up to 1 meter (3.3 feet) in height and a similar spread of 60-90 cm (2-3 feet) wide, forming a polite green bush with a textural silhouette. The plant has erect, decumbent, or prostrate stems that become woody with brown bark as they age. Six subspecies exist with varying sizes: subspecies acutifolia is a carpet-forming variant reaching only 150mm, while subspecies connivens and robusta can grow to 1 meter tall.

Crassula tetragona thrives in temperatures between 50°F (10°C) and 75°F (24°C). It can tolerate brief exposure to temperatures as low as 30°F (-1°C), though some growers report survival in the low 20s°F. Protect from prolonged frost and extreme temperature fluctuations, which can damage leaves and stems. In USDA zones 9-11, it can grow outdoors year-round; in colder climates, bring indoors during winter.

Crassula tetragona can grow outdoors year-round in USDA hardiness zones 9-11 where temperatures stay above 30°F (-1°C). It's excellent for xeriscapes, rock gardens, retaining walls, and as low informal hedging in frost-free regions. In colder climates, grow in containers that can be moved indoors during winter. The plant is native to rocky slopes and dry scrubland in South Africa.

Crassula tetragona propagates easily from stem cuttings. Cut a healthy 5-7cm stem section and let the cut end dry for a day or two to callus over. Plant the cutting in well-draining potting mix and maintain light moisture until roots develop in 2-6 weeks. Buried bands on stems where old leaves attached will generate new roots. Leaf cuttings can also work, though stem cuttings are more reliable. Seeds can be sown in autumn for propagation as well.

Crassula tetragona responds well to pruning and can be shaped for bonsai cultivation. Trim the top to promote branching and bushier growth. As the plant matures, stems become woody, making it ideal for succulent tree forms. Always sanitize pruning tools before cutting, and only prune after the plant has established a stable root system. Spring is the best time for significant pruning. Remove any dead or damaged stems to maintain plant health.

Crassula tetragona does not require frequent repotting—only when it outgrows its current container or the soil becomes compacted. Spring is the best time to repot. Use a slightly larger pot with drainage holes and fresh well-draining soil. Shallow pots work well as the plant has fibrous roots. When repotting, handle the woody stems carefully and allow a few days for any damaged roots to callus before watering.

Crassula tetragona is generally pest-resistant but can occasionally be affected by mealybugs, aphids, and spider mites. Inspect regularly and treat infestations with rubbing alcohol or insecticidal soap. The most common problem is root rot caused by overwatering and poor ventilation—LLifle notes that 'nearly all problems occur as a result of overwatering and poor ventilation.' Ensure well-draining soil and allow it to dry completely between waterings to prevent fungal issues.

Six subspecies of Crassula tetragona are recognized: subspecies acutifolia is a carpet-forming shrublet reaching 150mm; connivens is stiffly upright to 1m with upward-pointing branches; lignescens is the most common, with wiry woody branches to 800mm; robusta is a robust shrubby form to 1m; rudis is sparsely branched to 250mm; and tetragona (the type subspecies) is compact at 100-200mm. Each subspecies has distinct growth habits and geographic distributions across South Africa.

Crassula tetragona has limited documented traditional medicinal use. In South African folk medicine, leaves were historically boiled in milk as a remedy for diarrhea. However, this use is not widely practiced today and the plant is primarily cultivated for ornamental purposes. Given that many Crassula species contain compounds toxic to pets, any medicinal use should be approached with caution.

Crassula tetragona is popular for bonsai cultivation due to its tree-like appearance with woody trunk and needle-like leaves. It's excellent for succulent combination planters, rockery gardens, retaining walls, and as a feature specimen. In frost-free regions, it works well as low informal hedging. The plant is commonly used in xeriscaping and drought-tolerant landscapes due to its minimal water needs. Its unique form also makes it popular for holiday decorative displays as a 'miniature pine tree'.