Parodia werneri
| Light | Bright light with some protection from the harshest afternoon sun |
|---|---|
| Water | Regular in the growing season; keep drier and cool in winter |
| Soil | Free-draining mineral-rich mix (see Soil and potting mix) |
| Temperature | Keep above freezing; roughly USDA zones 9b–11 |
| Propagation | Seed (primary); occasionally from offsets |
| Toxicity | Non-toxic to cats and dogs |
Parodia werneri is a small, globular cactus from southern Brazil, best known for its unusually coloured flowers — a rich purple-red to magenta that is uncommon among cacti. A yellow-flowered form also occurs naturally and is widely grown in collections. It belongs to the genus Parodia, and older references may list it under its former name Notocactus uebelmannianus, or under other names in the genus Notocactus.
Description
Parodia werneri forms a solitary, somewhat depressed-globular body, usually flattened at the top and broader than it is tall. The glossy dark green stem is divided into a moderate number of low, rounded ribs, along which sit woolly areoles bearing short, fine, appressed spines that are more decorative than fierce; a nearly spineless form is also known. Young plants stay compact, and the species tends to remain single rather than clustering, though it can offset occasionally.
The flowers appear near the crown in spring and early summer. They are moderately sized — around 5 cm across — and open into a short, glossy funnel. Their colour is the notable feature: in the type form a rich purple-red to magenta, a shade unusual among cacti, while the well-known yellow form produces bright golden blooms.
Distribution and habitat
The species is native to southern Brazil, in the state of Rio Grande do Sul, where it grows in grassland and among rocky outcrops. Plants typically root in gritty, well-drained ground, often nestled among low vegetation and rocks that give a little shade and shelter. Much of its natural range has been converted to arable farming and grazing pasture, and the species is considered threatened in the wild. The regional climate brings a warm, moist growing season and cooler, drier conditions in winter — a rhythm worth mimicking in cultivation.
Cultivation
Parodia werneri is an easy, forgiving cactus that tolerates a beginner's mistakes. Plant it in a free-draining, mostly mineral mix and give it bright light, with a little protection from the fiercest afternoon sun to keep the body from scorching. During the warm months it appreciates more generous watering than many desert cacti, always allowing the mix to dry before watering again.
Through winter, keep the plant cool and dry to encourage a proper rest and reliable flowering the following season. A cold, dry winter rest is one of the surer ways to bring on those blooms. See Repotting for general potting technique.
Propagation
Seed is the usual and most reliable method, and it is how both the purple-red and yellow forms are typically raised. The fine seed germinates well on a warm, moist mineral surface and seedlings grow at a reasonable pace. Where a plant produces offsets, these can be removed and rooted as a vegetative alternative. See Propagation — seed and Propagation — offsets for full technique.
Common problems
- Rot — the commonest cause of loss, almost always from a slow-draining mix or overwatering, especially if the plant is watered while cold in winter.
- Etiolation — too little light makes the flattened body dome upward and pale, spoiling its neat symmetry.
- Pests — mealybugs (white fluff in the areoles and around the roots) and red spider mites (fine webbing and a bronzed skin) are the usual offenders; see Pests and diseases.
See also
- Parodia — the genus overview
- Soil and potting mix · Watering · Repotting · Propagation — seed · Propagation — offsets