Fishbone cactus care guide

The fishbone cactus grows flat, zigzag stems that look like fish skeletons or ric rac trim. It has no real spines. It is a jungle cactus from Mexico that grows on trees, not in the desert. The stems arch up, then trail down, which makes it a great hanging plant. It is easy to grow and easy to share.

Light

Give it bright indirect light. An east window is ideal. A few hours of soft morning sun is fine and can blush the stems purple.

Hot afternoon sun yellows and scorches the stems. In low light, new stems grow thin and round instead of flat.

Water

This is a jungle cactus. It needs more water than a desert cactus. Water when the top half of the soil is dry. Water until it drains, then empty the saucer.

In winter, let it dry a bit more. Soggy soil rots the roots. Read how to tell if a houseplant is overwatered or underwatered.

Soil and potting

Use a chunky mix of cactus soil and orchid bark. Its roots need air.

It likes a snug pot. Repot every two to three years in spring. See how to repot a houseplant step by step.

Humidity and temperature

Average room air is fine. It grows faster with more humidity.

Keep it between 16 and 27°C (60 and 80°F), and above 10°C (50°F).

Feeding

Feed monthly in spring and summer with a balanced liquid fertilizer at half strength. Skip feeding in fall and winter.

Flowers

A mature fishbone cactus can bloom in fall with large, white, sweet-smelling flowers. They open at night and last a day or two. Indoor plants do not bloom often. A cooler, drier rest in winter, around 13 to 16°C (55 to 60°F), and bright light in summer give it the best chance.

Aerial roots

Thin brown roots may grow from the stems. They help it climb in the wild. Leave them, or trim them if you like. They do not harm the plant.

Pruning

Cut long or untidy stems at a joint with clean scissors. Use the cuttings to grow new plants.

Propagation

Cut a stem section 10 to 15 cm (4 to 6 in) long. Let the cut end dry for a day. Push the cut end 2 cm (1 in) into moist, chunky mix. Keep it in bright indirect light and water when the mix is half dry. Roots form in two to four weeks.

Problems

What you see	Most likely cause
Shriveled, limp stems	Thirst, or roots rotted from too much water
Mushy stem base	Rot from soggy soil
Yellow, scorched stems	Too much direct sun
Thin, round new stems	Not enough light
Purple or red blush	Strong light. This is normal.
White, cottony spots	Mealybugs

Pests

Mealybugs and scale are the most common pests. Check the notches along the stems. Dab them with rubbing alcohol on a cotton swab. Fungus gnats can show up in soil that stays wet.

Pet safety

Fishbone cactus is not on the ASPCA list of toxic plants. It is often sold as pet safe. Its jungle cactus cousins, such as Christmas cactus and mistletoe cactus, are on the ASPCA non-toxic list.

Varieties

• Disocactus anguliger has flat, rounded zigzag lobes. It is the common fishbone cactus.
• Selenicereus anthonyanus, also sold as ric rac cactus, has larger, pointed lobes and big pink flowers. It grows larger and needs more room.
• Fernleaf cactus, Selenicereus chrysocardium, has wide, deep-cut stems like fern fronds. It grows huge.