Cactus Care: Fairy Castle, Spiral, Bunny Ear + More
Indoor desert cacti, including fairy castle (Acanthocereus tetragonus), spiral cactus (Cereus forbesii 'Spiralis') and bunny ear (Opuntia microdasys)
At a glance
| βοΈ Light | As much sun as possible. |
|---|---|
| π§ Water | When the soil is completely dry. Very little in winter. |
| πͺ΄ Soil | Gritty: our Arid Potting Mix. |
| π‘οΈ Temp | 10β30Β°C. Cool winters are good. |
| π¨ Humidity | Dry is perfect. |
| πΎ Pets | Pet safe Most cacti are non-toxic, but spines can hurt. (Euphorbias look like cacti but have toxic sap.) |
| π± Care level | Beginner Needs sun |
| π Grows to | 10 cm to 1 m+, depending on type. |
Cacti are built for sun and drought, which makes them some of the easiest plants to keep alive, as long as you give them light and resist the urge to water. Our best sellers include the turreted fairy castle, the twisting spiral cactus and the polka-dotted bunny ear.
Light + placement
Cacti need your sunniest spot: a south or west window, right up against the glass. A few hours of direct sun every day keeps them compact and healthy. In low light they stretch thin and pale toward the window.
Watering
Water thoroughly until it drains, then let the soil dry out completely. In spring and summer that's roughly every 2β3 weeks. From November to February, water only once a month or less; a cool, dry winter rest encourages flowers.
Soil + repotting
A gritty, fast-draining mix like our Arid Potting Mix in a pot with a drainage hole; terracotta is ideal. Repot every 2β3 years. Wrap the cactus in folded newspaper or use thick gloves to handle it.
Feeding + upkeep
Feeding: We feed with Kelpy, a gentle plant food made from BC kelp. Mix 1 teaspoon into 1 litre of water and use it every other time you water. Kelpy is gentle enough to use year-round. Our rule of thumb: if your plant is putting out new growth, even in winter, keep feeding. If it's resting, you'll be watering less, so it gets fed less too.
A light sprinkle of worm castings on top of the soil every few months gives it a slow, natural boost (keep it thin so the gritty mix still drains fast). Prefer a granular food? BIOS Natural Plant Food mixes into the top layer of soil (about 1 tablespoon per 6-inch pot) once a month while your plant is growing. A little white fuzz on the soil afterwards is normal; it's the helpful fungi at work.
Dust with a soft brush.
Common problems
| What you see | Likely cause | What to do |
|---|---|---|
| Soft, mushy, dark base | Overwatering, rot | Stop watering; cut away rot or take a healthy cutting. |
| Thin, pale, stretched growth | Not enough sun | Move to the sunniest window. |
| Brown or white scorched patches | Sudden strong sun | Increase sun gradually. |
| Shrivelled, wrinkled | Very thirsty | Water deeply. |
| White cottony spots | Mealybugs | Dab with rubbing alcohol; treat with Houseplant Spray. |
Varieties we carry
Same care for our desert cacti. Holiday and jungle cacti like Christmas cactus and rhipsalis need different care. Only what's in stock online right now is shown.
Frequently asked questions
How often should I water a cactus?
Only when the soil is completely dry: every 2β3 weeks in summer, monthly or less in winter.
Are cacti safe for pets?
Most are non-toxic, but the spines can hurt. Euphorbias look similar but have toxic sap.
Can a cactus live in low light?
Not well. Cacti need several hours of direct sun.
How do I get my cactus to flower?
Lots of sun in summer and a cool, dry rest in winter.
Cactus care kit
- Arid Potting Mix: Our fast-draining Soil Bar mix for plants that like to dry out.
- Plant Cleaning Gloves: Protect your hands when handling and repotting spiny plants.
- Kelpy Plant Growth Booster: Gentle BC kelp plant food you can use year-round.
- Worm Castings: A slow, natural boost from our Soil Bar. Top-dress every few months.
Bring your plant (or a photo) to 515 Chatham St #103 and we'll take a look. Open 11β5, 7 days a week, with street parking nearby. Get directions β
More plant care guides
Lithops Β· Indoor Palms Β· Peace Lily Β· Fittonia Β· Pilea Β· Pitcher Plant Β· String of Pearls Β· Olive Tree Β· All plant care β