This is one of the more popular and well known of the Plectranthus or spurflowers. It is known for its pretty flowers which are larger than those of most other plectranthus.

The genus name Plectranthus means "spur flower" after the spurred corolla tube which is a characteristic of the species. The species name saccatus means "bag-like" and refers to the shape of the flower tube. The large petals distinguish the stoep jacaranda from others in the genus. The flowers bear a vague resemblance to the Jacaranda mimosifolia flower, hence the common name. (It is no relation to the jacaranda). Since it is a shade loving plant, it is often used as a "stoep" (patio) plant. The colour of the flowers is also similar to those of the jacaranda and ranges from blue to lilac and sometimes white. There are a number of different varieties and cultivars of this plant.

Plectranthus saccatus is a soft, semi-succulent with a woody base. The branches are tinged with purple and have soft hairs. The leaves are bright green, have large teeth along the margin and are dotted with transparent gland dots beneath. The shrub reaches a height of about 1.2m. The flowers may have some purple markings and are borne on one side of the stem. Flowering occurs from November to May.

Plectranthus saccatus belongs to the sage or mint family (Lamiaceae) which has a very large representation in the Mediterranean regions. The family is characterised by aromatic leaves arranged in opposite pairs (decussate) and the two-lipped corolla.

This species is found naturally in the Eastern Cape and KwaZulu Natal growing in forests. It also grows in semi-shade and in rocky areas.

Growing Plectranthus saccatus

This plant is very easy to propagate from cuttings - even in a glass on the window-sill! Take softwood cuttings from the tips of healthy plants. They dry out quickly so be careful to keep them moist until you are ready to put them into trays. Work in the shade on a clean surface. Root cuttings in sand or well drained medium to prevent rotting, but do not allow to dry out. No rooting hormone will be required.

The stoep jacaranda is sensitive to frost, however, because it likes a shady position it is usually protected from the worst of the frost and the cold winds. Fortunately flowering has usually finished by the time the first frosts appear. In early spring the shrubs may be cut back to keep them neat and bushy. It is suitable for mass plantings - especially if you mix the white and blue forms. It also makes a lovely container plant for a shady spot.

References

• Codd, L.E. 1985. Flora of Southern Africa. 28:4. Botanical Research
  Institute. Pretoria
• Joffe, P. 1993. The Gardener's Guide to South African Plants. Delos. Cape Town
• Joffe, P. 2001. Creative Gardening with Indigenous Plants: A South African Guide. Briza. Pretoria.
• Pooley, E. 1998. A Field Guide to Wild Flowers of KwaZulu-Natal and the Eastern Region. Natal Flora Publications Trust. Durban.

L. Mashinini and A. Aubrey
Witwatersrand National Botanical Garden
March 2002