Drosera slackii is a South African perennial with a strong visual identity: broad, often intensely coloured leaves arranged in an open rosette. Close inspection reveals more useful identifying characters than redness alone, while published cultivation reports show why it should not simply receive the summer-dry treatment used for every seasonal Cape sundew.
Recognising the plant
Nigel Hewitt-Cooper describes rosettes reaching about 7.5 cm across, leaves with a narrowed and expanded outline, conspicuous red stipules, and coarse red hairs beneath the leaves. Older plants can develop a pedestal of accumulated leaf remains beneath the living rosette. The species commemorates Adrian Slack and was formally named in 1987. Hewitt-Cooper’s species account
The red stipules and coarse hairs deserve a place in identification photographs. Colour changes with growing conditions; structural characters provide a stronger basis for comparison. Include a view from the side when documenting an older plant so that the living crown and old leaf column are both visible.
Position among the Cape rosettes
The 2018 revision of Western Cape rosette sundews recognises D. slackii and separates it in the identification key using fleshy, deeply divided red stipules and conspicuous dark hairs on the lower leaf surface. These characters help distinguish it from species with pale, papery stipules. Fleischmann’s taxonomic revision
This matters when plants are exchanged under short labels such as “red South African sundew”. Preserve a full botanical name and the supplier’s accession details, even if identification is later revised. Several attractive red rosettes can share a bench without sharing a species identity.
Light, water and seasons
Hewitt-Cooper’s nursery grows the species in strong light, recommends a winter minimum around 7°C, and describes keeping it wet in summer and damp in winter. This is a grower’s working regime rather than an experimentally established tolerance boundary. It does not justify deliberately freezing a plant or drying it as though it were a tuberous sundew. Grower’s cultivation guidance
His longer account describes periodically flushing pots from above with rainwater, following observations of reduced vigour in plants left for years in the same medium. Mineral accumulation was his proposed explanation; the account is observational, not a controlled test of causation. Long-term pot observations
For a home collection, the useful question is whether fresh leaves remain healthy. Record water source, medium age and changes in crown size. A photograph of the newest growth is often more informative than a demand for every old leaf to remain colourful.
An intriguing scent observation
Andreas Fleischmann reported a lemon-like scent from the foliage of cultivated and wild D. slackii. He explicitly distinguished that observation from proof that the scent attracts prey: its relationship to capture had not been established in that account. Firsthand observations of sundew scent
It is an excellent example of how an encyclopedia can describe an interesting feature without turning a plausible explanation into an established mechanism. A scented leaf, a visiting fly and a successful capture are separate observations.
Maintaining useful propagation records
Keep vegetatively produced plants connected to their parent accession, and record seed-grown offspring separately. Two pots originating from one plant do not establish genetic diversity. Likewise, a locality written on a purchased label is provenance to preserve, not proof independently supplied by this article.
Avoid repeatedly stripping the old leaf pedestal for appearance alone. Inspect it as part of the whole plant, and make any cleaning or repotting decision according to the condition of the crown and medium. This species’ mature form can be part of its appeal, provided that the living growth remains sound.
Nano Nursery Drosera Encyclopedia — species profile. Related core chapters: 5, 6 and 29. Reviewed 23 September 2026. Cultivation guidance concerns established plants; recently deflasked plants need separate acclimatisation.
