Cacti (general) care guide
Also known as: Cactus, Cactaceae
Pets and children
Caution advised
Most kinds have no reported toxicity, but spines and tiny glochids pierce skin and mouths, and a few, such as peyote and San Pedro, contain hallucinogenic alkaloids; keep them out of reach and consult a veterinarian or doctor if spines lodge or any is eaten.
How often to water Cacti (general)
- Spring–Summer (Mar–Sep)
- Every 10 days
- Most are summer growers: as a guide, water until it drains from the pot a few days after the soil has dried through, and more lightly in the evening in midsummer.
- Autumn (Oct–Nov)
- Every 14 days
- As it cools, stretch the interval to about one to two weeks after the soil dries.
- Winter (Dec–Feb)
- Every month
- Dormant in winter: keep it nearly dry, moistening lightly about once a month on a warm morning, as a guide.
Light and placement for Cacti (general)
Generally a sunny, airy spot is the guide, though many slow in the Japanese midsummer and behave like spring-and-fall growers, and some, such as chin cacti, prefer partial shade.
Overwintering Cacti (general)
Overwintering guide: 5°C (41°F) or above
Hardiness varies widely, but most types overwinter if kept above about 5°C: rest them dry at a bright window indoors, back from the glass on cold nights, as a guide, and avoid the mix of cold and damp.
Fertilizing and repotting Cacti (general)
Fertilizer
Feed lightly: diluted liquid fertilizer about once a month from April to September, or a small dose of slow-release in spring, and none during dormancy.
When to repot
Spring–Summer (Mar–Sep)
Common problems with Cacti (general)
- Overwatered in winter, the roots rot and the collapse shows only in spring.
- In a dim room it grows thin and tall, and the shape does not recover.
- Water left in the saucer rots the base.
Tips for growing Cacti (general)
- Judge watering by lifting the pot: a light pot is a dry one.
- Repot in spring into dry mix and water a few days later.
- Handle spines with thick gloves or a folded newspaper.
These are AI-generated general guidelines. They vary with the variety, the placement and the pot size. For effects on pets or children, consult a veterinarian or a doctor.
Keep your plant log going
Greenery is a free app that keeps your plant care going, with watering reminders and photo records. Available on iOS and Android.
