Moon Cactus — Growing reference
| Scientific name | Gymnocalycium mihanovichii |
|---|---|
| Seed germination (days) | 14–30 |
| Soil temperature for germination (°C) | 21.1–26.7 |
| First harvest or flowering (days) | 365–730 |
| Measured from | Transplant |
| Plant spacing (cm) | 10.2–15.2 |
| Mature height (cm) | 7.6–15.2 |
| Mature spread (cm) | 10.2–15.2 |
| USDA hardiness zones | 9–11 |
| Light | Partial sun |
| Water | Low |
| Sowing method | Division |
Growing directions
Grow as a houseplant or xeriscape container in bright, indirect light to partial sun in fast-draining cactus mix; the green species form tolerates more direct sun, while the brightly colored grafted forms sold as 'moon cactus' need protection from intense direct sun. In its natural green form this small, rounded, ribbed cactus from Paraguay and Brazil bears attractive pale pink to white flowers, but it is far better known in cultivation for its chlorophyll-free color mutants — brilliant red, orange, yellow, or pink globes — which lack the green pigment needed to photosynthesize and are grafted as small caps atop a green Hylocereus or Selenicereus cactus rootstock to survive. These colorful grafted 'moon cactus' combinations are common, inexpensive houseplants but are ultimately temporary, since the graft union eventually fails after a few years even with good care, at which point the colorful top can sometimes be re-grafted onto fresh rootstock. Water sparingly, avoid direct hot sun which can scorch the color mutant tops, and expect the brightly colored forms to need eventual regrafting rather than indefinite growth on their own roots.
Source and local conditions
Typical planning ranges from OpenPlantDB (CC0). Cultivar, climate, season and growing method can change these values. Confirm the seed label and local guidance before planting.
Source & verification
OpenPlantDB · CC0