How often should I water it?

Water thoroughly when the top few centimeters of soil are dry, but reduce watering significantly in winter.

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

Rattail cactus — Photo by Diana Fuentes (CC BY-SA) via iNaturalist

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.

Another photo of Rat's Tail Cactus — Photo by Peter Quakenbush (CC BY) via gbif

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: Late winter to mid spring

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 30°C
Humidity: 40 to 60%
Drought tolerance: Moderate
Lifespan: Perennial, typically 10 to 20 years with proper care.
Deer and rabbits: Moderate

Signs it needs repotting

Roots growing out of the drainage holes.
Stems looking stunted or failing to grow.
Soil breaking down and losing its structure.

Safety

People: This plant is not considered toxic to humans.
Pets: This plant is generally considered non toxic to cats and dogs.
Children: Keep this plant out of reach of children because the fine spines can cause painful skin punctures.
Contact allergens: The fine, hair like spines can cause mild skin irritation if handled without gloves.
Airborne allergens: There are no known respiratory allergens associated with this plant.
Edibility: While the fruit is technically edible, it is not commonly consumed and lacks significant culinary value.

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: 0.15 to 0.3m
Spread: 0.6 to 1.2m
Leaves: bright green, evergreen
Flowers: pink, magenta, 5 to 8cm
Fruit: red, Late summer

Problems to watch for

MealybugsCommon
Root RotCommon
Fungus GnatsUncommon
Spider MitesUncommon

By symptom

Check your rat's tail cactus from a photo

Pocket Botanist looks at a photo of your plant and tells you what's wrong and what to try first.

Growing it

Propagation: cuttings, seed
When to plant: spring
Overwintering: Move the plant indoors before the first frost. Keep it in a cool, bright spot and water very sparingly to encourage a rest period.
In containers: This plant is perfect for hanging baskets, which allow its long stems to trail naturally without touching the ground.

Stem cuttings

1. Cut a healthy stem segment about 10 to 15 centimeters long.
2. Allow the cut end to callous over for a few days in a dry spot.
3. Insert the calloused end into a well draining cactus potting mix.
4. Keep the soil barely moist until roots develop.

Group this cactus with other epiphytic plants that appreciate good airflow and bright, indirect light.

Grows well with

Orchid Cactus — They share similar light and humidity requirements for indoor display.
Burro's Tail — Both plants look stunning in hanging baskets and enjoy similar watering schedules.

Similar species

Queen of the Night — It is another trailing cactus with impressive, though nocturnal, blooms.

Science

Family: Cactaceae
Genus: Aporocactus
Order: Caryophyllales
Class: Magnoliopsida
Native range: Mexico
Conservation: It is not currently listed as endangered, but wild populations are threatened by habitat loss.

It grows as an epiphyte in its native habitat, clinging to trees and rocks in humid forests.

Value to wildlife: nectar source
Pollinators: hummingbirds
Uses: hanging baskets, indoor specimen, greenhouse display

Through the year

JFMAMJJASOND

Flowering

Fruiting

Foliage

Ecological indicators

Salinity: 2/9
Soil reaction: 6/9
Light: 7/9
Moisture: 3/9
Nutrients: 3/9
Temperature: 8/9

Taxonomy resolved against GBIF.

Questions people ask

How often should I water it?: Water thoroughly when the top few centimeters of soil are dry, but reduce watering significantly in winter.
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, referring to the dense spines, while flagelliformis refers to the whip like shape of the stems.

Good to know

It is commonly called the Rat Tail Cactus because of its long, slender, spiny stems.
The flowers are zygomorphic, meaning they have bilateral symmetry.
It thrives in bright, indirect light but can handle some direct morning sun.
The stems can grow up to 1 meter long in ideal conditions.

Keep your rat's tail cactus growing

This page is a general guide. Save your plant in Pocket Botanist and you get care reminders timed for this plant, plus a care history that shows what worked.

Get the app

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.