Gymnocalycium

Family Cactaceae. Native range - Bolivia, Paraguay, southern Brazil, Uruguay and Argentina.

The genus name comes from the Greek words gymnos - 'naked' and calyx - 'cup'. This extensive South American genus comprises about 100 species and numerous varieties of cacti. Gymnocalycium grows solitary or in groups. These stem succulents are found in Argentina, Brazil, Bolivia, Uruguay and Paraguay. Stems are globular, green. With age the number of ribs and spines changes. Spines most often grow in a spider-like fashion, pressed to the stem. Flowers are white or pinkish.

According to different authors, the number of species ranges from 60 to 80. In nature they occur on plains and ascend into mountains up to 1000 m. They grow among grasses and rocks on well-drained soil. Gymnocalyciums are notable specimens in the world of cacti. They are stately and robust; their globular stems with large ribs and often very beautiful spines inspire confidence and calm. The beautiful silky flowers of various shades are so characteristic that anyone who has seen them once can easily distinguish Gymnocalycium from other cactus genera.

Gymnocalyciums are undemanding in cultivation, easily grow on their own roots, resistant to pests and diseases and are less demanding in light than most other cacti.

Cacti of this genus prefer nutritious loose soil, poorly tolerate intense heat and excess moisture. They respond well to the humid warmth of cloches and greenhouses.

Temperature: 7-30 °C, in winter 15 °C

Light: bright, shading necessary on sunny days.

Humidity: low.

Watering: regular during the growing season, limited in winter.

Fertilization: every 2-3 weeks with a half-strength flowering fertilizer in spring and summer.

Propagation: by offsets from late spring to early summer at 21-22 °C

Soil: a mix of leaf soil, topsoil, humus, peat, sand (1:1:1:1:1) or a special cactus substrate.

Possible problems: mealybugs.

Use: on south-facing windowsills and in hanging baskets. Used for indoor greening of various rooms, in floral compositions with other succulents.