STREPTOCARPUS (CAPE PRIMROSE)
The Cape of Good Hope section of South Africa is home to many ornamental plants, none more beautiful than the Cape Primrose. But it is not very well known and, as a result, hard to find.
There are three types of Cape Primrose, all very different and all worth growing. One is S. saxorum. It has smaller leaves than the other two; they’re about one inch long, a fuzzy gray green and oval in shape. The leaves overlap to form a low-growing mat. It bears trumpet-shaped lavender flowers and is also called the Dauphin Violet. Though it isn’t a violet, it isn’t a primrose either, being instead a gesneriad related to the African Violet and Gloxinia. It blooms for months, primarily through summer and fall.
Another group is the Wiesmoor Hybrids. The 1 ½ to 2 inch flowers come in white, pink, red, purple, and shades in between, often with markings of contrasting colours. Plants grow 6 to 8 inches tall, leaves are tongue shaped as much as 10 inches long and the wing flower spikes rise above the foliage. They stay in bloom for up to 2 months.
The third group, the Nymph hybrids, bloom over the longest period of either group. They’re larger than the Wiesmoor hybrids, 10 to 12 inches tall with flowers 1 to 2 inches across on slender stems that rise above tongue-shaped foliage. If conditions are ideal, these plants can bloom from May through to October and are available in a variety of blue to purple shades as well as white.
All Cape Primroses need essentially the same care. They require bright, indirect light; a north facing window is perfect. If they don’t get enough light, their leaves become floppy and the flowers droop into the foliage. They are tropical plants, so night temperatures should be in the high 60s and the days 10 degrees warmer. A potting medium providing good drainage is a must. They’re slow growers so they don’t need repotting too often, but when they do, it can be done anytime of the year. All Cape Primroses need to be kept constantly moist and fed monthly through their growing season. For the Saxorum group, which has no rest period, this routine is applied all year. The Wiesmoor and Nymph hybrids go through a semi-rest period after they flower and need less water and no food during that time. Cape Primroses can take quite a bit of punishment. They can wilt down to soil level, which would kill many plants, and completely revive a few hours after a good watering.
The Saxorum plants are best started by stem cuttings, but they can be propagated by seed. The best way to increase a collection of Wiesmoor hybrids is by division, though new plants can be started from seed as well. Keep in mind that the seeds are as fine as dust and can be easily blown away or drown. Seed can be sown either in a mason jar laid on its side in a bed of sand or in a flowerpot. The crucial thing is to keep the container sealed, either with the top of the jar or with a plastic bag over the pot. This ensures that the tiny seeds don’t need water while they are germinating. Keep them in a warm, bright, sunless spot.
The Nymph hybrids can’t be started from seed but can be easily divided, the best time being early spring before new growth starts.
All three types are strategically utilized at Government House when a boost of colour is needed, especially during the fall season of the year.