Cacti

Columns, globes or trailers: how to choose

The upright forms carry a whole garden bed on their own. The Cowboy Cactus (Euphorbia acrurensis) makes a classic branched column to about 3m, and the Candelabrum Cactus reaches 4m in a frost free spot. Both are technically succulent euphorbias rather than true cacti, which matters for one reason: their milky sap irritates skin and eyes, so plant them with gloves on. Among the true cacti, the Golden Barrel (Echinocactus grusonii) is the collector's globe, taking decades to reach 0.6m, while Silver Ball and Thimble Cactus stay under 30cm for pots and rockery pockets. The odd one out is the Coral Cactus, a thornless trailing jungle species that suits a hanging basket indoors.

Where cacti grow well in Australia

Desert cacti are built for arid, Mediterranean and warm temperate climates: think Perth, Adelaide and everywhere inland. Most here are frost tender or take light frost only, so in cold districts grow them in pots you can shift under cover for winter. On the humid east coast the enemy is wet feet, not heat; a raised rockery, a north facing wall and gritty free draining mix keep them healthy through a Brisbane or Sydney summer. Half the range also grows well indoors on a bright windowsill, and the wider succulents and cacti collection adds softer companions.

Potting, position and soil

Full sun suits nearly everything here, with the Coral Cactus preferring bright shade. Use a dedicated cactus mix, never garden soil, in a pot only slightly wider than the plant, and unglazed terracotta dries fastest. In the ground, mound the bed 20cm to 30cm above grade and mulch with gravel rather than bark. Keep the fiercely spined Golden Barrel a metre back from paths, and site all spiny varieties out of reach of children and pets.

Watering and feeding

Water deeply, then let the mix dry out completely; in summer that is roughly fortnightly for pots, and in winter most cacti want almost nothing. Soft, discoloured growth means too much water, not too little. Feed once in spring with a half strength low nitrogen fertiliser. Our guide to growing the Cowboy Cactus covers the tall euphorbias in more detail.

Common questions

Are cacti safe around pets?

Two here carry our Pet Friendly flag: the thornless Coral Cactus and the Thimble Cactus, which is non toxic but still spiny. The euphorbias are toxic if chewed and their sap irritates, so keep them out of reach.

Can I grow cacti indoors?

Yes, in the brightest spot you have. Coral Cactus, Silver Ball and Thimble Cactus all handle indoor life beside a sunny window. A column euphorbia will cope indoors for years if it gets several hours of direct sun.

How fast do cacti grow?

Slowly, which is part of the appeal. A Golden Barrel adds only a few centimetres a year, so buy close to the size you want to look at.

How are cacti delivered?

Carefully wrapped and delivered Australia wide, with delivery from $29.95 and no minimum order. Every plant carries our 30 day healthy plant guarantee.