Parodia concinna
| Light | Bright light with a little shade from harsh summer afternoon sun |
|---|---|
| Water | Regularly in the growing season, letting the soil dry between waterings; keep dry in winter |
| Soil | Fast-draining but slightly retentive mineral mix (see Soil and potting mix) |
| Temperature | Keep above freezing; a cool, dry winter rest around 5–10 °C encourages flowering |
| Propagation | Seed (primary); occasionally by offsets |
| Toxicity | Non-toxic to cats and dogs |
Parodia concinna is a small, flattened, globular South American cactus best known for producing large, glossy yellow flowers that seem oversized against its modest body. Long grown under the name Notocactus concinnus, it is one of the easiest and most reliable of the ball cacti to bring into bloom, which has made it a long-standing favourite with beginners and windowsill growers alike.
Description
Parodia concinna forms a solitary, slightly depressed globe, typically only a few centimetres tall and somewhat wider than it is high. The body is fresh green and divided into numerous low, rounded ribs broken into gentle tubercles. Each areole carries a spreading fan of fine, pale bristly radial spines and a few short, stouter central spines, often faintly yellowish to brown, so that the plant appears combed rather than fierce.
The flowers are the main event. Borne in a cluster from the woolly crown in spring and early summer, they are broad, funnel-shaped and a rich glossy yellow, frequently as wide across as the plant itself. A ring of reddish stigma lobes at the centre provides a striking contrast. Blooms open over several successive days in sunshine and close at night.
Distribution and habitat
The species is native to southern South America, where it grows among grasses and low vegetation on rocky hills and outcrops in southern Brazil and Uruguay. In habitat it experiences warm, moist summers and cooler winters, and often nestles into gritty pockets of soil with some shelter from surrounding plants — conditions worth keeping in mind when it comes to cultivation.
Cultivation
Parodia concinna is an accommodating plant and one of the better Parodia species for a first-time grower. Unlike many desert cacti, it appreciates more regular water through the growing season and dislikes being baked bone-dry for months on end, so a mineral mix with a little more moisture retention suits it well. Water thoroughly whenever the soil has dried, then allow it to approach dryness again; ease off sharply in autumn.
Give it bright light for good flowering and compact growth, with a little shade from the fiercest afternoon summer sun to prevent scorching. The single most important trigger for those big yellow flowers is a cool, dry winter rest — keep the plant cool and essentially unwatered through the coldest months, protected from frost. See Watering and Repotting for general technique.
Propagation
Seed is the usual and most productive method: it germinates readily on a warm, moist mineral surface and young plants grow at a satisfying pace, often flowering while still small. Mature plants may in time produce a few offsets or cluster with age, and these can be removed and rooted once they have calloused. See Propagation — seed for a full walkthrough.
Common problems
- Rot — the most frequent cause of loss, usually from waterlogged soil or winter watering; the base or crown softens and discolours.
- Etiolation — too little light makes the body pale and elongate upward, spoiling its flat, symmetrical shape and reducing flowering.
- Failure to flower — nearly always the result of a warm or wet winter; a genuine cool, dry rest is what sets the buds.
- Pests — mealybugs (white fluff in the areoles) and red spider mites (fine webbing, 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