How often should I water it?

Water it thoroughly when the soil is dry to the touch, but let it drain completely.

Does it need direct sun?

It prefers bright, filtered light rather than harsh, direct midday sun.

Plant guide

Rat's Tail Cactus.

Aporocactus flagelliformis

Pronounced dih-so-KAK-tus fla-jel-li-FOR-mis

Also known as rat-tail cactus

Aporocactus flagelliformis — Photo by Peter Quakenbush (CC BY) via gbif

The Rat's Tail Cactus is a stunning trailing succulent known for its long, slender, spiny stems. It produces vibrant, tubular pink to magenta flowers that look amazing in hanging baskets. This plant loves to bask in bright light and makes a fantastic statement piece.

At a glance

Care level: Easy
Plant type: Epiphytic cactus
Light: Bright indirect light with some morning sun
Indoor light: bright-indirect
Water: Every 7 to 14 days
Mature size: 100 to 150 cm long
Growth rate: medium
Hardiness: USDA 10 to 12
Bloom time: Spring to early summer

Care

Keep this cactus in a spot with plenty of bright, indirect light to encourage blooming. Allow the soil to dry out significantly between waterings, as soggy roots will cause trouble. Watch for shriveling stems, which often signal that the plant is thirsty.

Watering: Water thoroughly when the top few inches of soil are dry.
Feeding: Use a balanced liquid fertilizer during the active growing season.
Pruning: Trim back any damaged or overly long stems after the flowering period.
Repotting: Repot only when the plant has clearly outgrown its current container.
Soil: Well draining cactus and succulent mix
Soil pH: 6.0 to 7.5
Temperature: 10 to 27°C
Humidity: 20 to 50%
Drought tolerance: high
Lifespan: Perennial, typically 10 to 20 years.
Deer and rabbits: high

Signs it needs repotting

Roots growing out of the drainage holes.
Stems looking stunted despite proper care.
Soil drying out much faster than usual.

Safety

People: The plant is generally considered non toxic to humans, though the spines can cause mechanical irritation.
Pets: This plant is generally considered non toxic to cats and dogs.
Children: Keep this plant away from small children because the sharp spines can easily pierce delicate skin.
Contact allergens: The fine, hair like spines can cause skin irritation if handled without gloves.
Airborne allergens: There are no known significant respiratory allergens associated with this plant.
Edibility: This plant is not considered edible and should not be consumed.

How to identify it

Long, slender, cylindrical trailing stems
Stems covered in fine, bristly spines
Vibrant magenta or pink tubular flowers
Stems can grow several feet long

Height: 0.1 to 0.2m
Spread: 0.6 to 1.5m
Leaves: green, evergreen
Flowers: pink, magenta, 3 to 5cm
Fruit: red, yellow, Late summer

Common problems

Mealybugs — These small white insects hide in the crevices of the stems and suck plant sap.
Root rot — Overwatering leads to fungal decay of the root system.

Growing it

Propagation: cuttings, seed
When to plant: Spring
Overwintering: Move the plant indoors before the first frost. Reduce watering significantly during the winter months to allow the plant to rest.
In containers: It is perfect for hanging baskets, which allow the long stems to trail naturally without touching the ground.

Stem cuttings

Cut a healthy stem section 4 to 6 inches long.
Let the cut end callous over for a few days in a dry spot.
Insert the calloused end into a well draining cactus mix.
Keep the soil barely moist until roots develop.

Group plants with similar succulent needs to ensure you do not accidentally overwater your cactus.

Grows well with

Christmas Cactus — They share similar light and water requirements for indoor display.
Burro's Tail — Both plants look fantastic in hanging baskets and enjoy similar growing conditions.

Keep away from

Peace Lily — Peace lilies require much higher moisture levels than this cactus.

Similar species

Queen of the Night — It is another trailing epiphyte that produces showy flowers.

Science

Family: Cactaceae
Genus: Aporocactus
Order: Caryophyllales
Class: Magnoliopsida
Native range: Central and southern Mexico.
Conservation: This species is listed under CITES Appendix II, meaning international trade is regulated to prevent overharvesting in the wild.

It grows as an epiphyte on trees or on rocky cliffs in its native habitat.

Value to wildlife: nectar source
Pollinators: hummingbirds
Uses: hanging baskets, ornamental specimen

Through the year

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Flowering

Fruiting

Foliage

Ecological indicators

Salinity: 2/9
Soil reaction: 6/9
Light: 7/9
Temperature: 7/9
Moisture: 3/9
Nutrients: 3/9

Taxonomy resolved against GBIF.

Questions people ask

How often should I water it?: Water it thoroughly when the soil is dry to the touch, but let it drain completely.
Does it need direct sun?: It prefers bright, filtered light rather than harsh, direct midday sun.

Where the name comes from

The name Aporocactus comes from the Greek word aporos, meaning impenetrable, while flagelliformis refers to its whip like stems.

Good to know

It is native to the dry forests of Mexico.
The flowers are a brilliant magenta pink.
It thrives in bright, indirect light.
The stems can grow up to 6 feet long in ideal conditions.

Is your rat's tail cactus looking unwell?

This page is a general guide. Pocket Botanist diagnoses problems from a photo of your actual plant, works out watering for your light and conditions, and reminds you when care is due.

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This guide was generated with AI and checked against GBIF taxonomy. It is general information, not horticultural or veterinary advice. Read about how we build these guides.