Boobie Cactus (Fukurokuryuzinboku)

If you like a spiny plant that wants a sunny window and dry soil, the Madagascar palm with its tall spiny trunk fits the same spot and routine.

For a home with cats or dogs, the ponytail palm, listed by the ASPCA as non-toxic to cats and dogs, likes the same bright light and dry soil.

If the unusual shape is what drew you in, the fishbone cactus with its zigzag trailing stems is a cactus for bright rooms without strong direct sun.

It is Myrtillocactus geometrizans 'Fukurokuryuzinboku', a Japanese nursery cultivar of the blue myrtle cactus. In place of the usual straight ribs, its blue-green stems carry rows of rounded bulges, and spines are few or missing on young plants.

Its stems grow about 10 cm thick. Planted in the ground in a warm climate, the species can reach about 4 m, but kept in a pot indoors it stays far smaller and takes years to gain height.

Use a gritty cactus mix with extra perlite, pumice or grit so water drains fast. Our guide to the best soil mix for succulents and cacti shows what to look for, and a clay pot with a drainage hole helps the soil dry out between waterings.

In spring and summer, water until it drains from the bottom of the pot, then wait until the soil is completely dry before watering again. During the heating season in Ontario and Quebec, give only enough water to keep the stems from shrivelling, which can mean once every month or two. Most cactus losses happen in winter from watering too much.

No, a north-facing window does not give it enough light, especially during short Canadian winter days. Place it in a south-facing window, or a west-facing one as the next best choice.

The ASPCA plant database does not list this cactus, so its toxicity is not confirmed and it is safest to treat it as toxic. Keep it on a tall stand or in a room that cats, dogs and small children can't get into, since older plants can also grow short spines.

This is a normal winter rest caused by short days and cooler temperatures, and growth starts again in spring. Keep it bright, dry and above 10°C (50°F), and never leave it on a balcony or in a cold car in late fall, since temperatures below -4°C (25°F) can kill it.

Pests on cacti are most likely in winter, when the plant spends months indoors with the furnace running.

Mealybugs

Looks like: white cottony clumps in the folds between the bulges.

Fix: Dab each clump with a cotton swab dipped in rubbing alcohol.

Scale

Looks like: small brown bumps stuck to the stem.

Fix: Wipe them off with a cotton swab dipped in rubbing alcohol, or use an insecticide labelled for scale.

Short spines

Looks like: small spines at the growing points, more common on older plants kept in full sun.

Fix: Wrap the stem in folded newspaper before you lift or repot it.

Keep any plant with pests away from your other plants until it is clean, and wear gloves when you handle it.