Poison ivy.

At a glance

Care level

Easy

Plant type

Vine or shrub

Light

Full sun to deep shade

Indoor light

Bright indirect

Water

Every 7 to 14 days

Mature size

Up to 30 meters long

Growth rate

Fast

Hardiness

USDA 3 to 10

Bloom time

Late spring to early summer

Care

This plant is highly invasive and typically considered a weed. It requires no care and is best avoided entirely to prevent contact with its irritating oils. If you must remove it, wear protective clothing and never burn the plant material.

Watering

It is highly drought tolerant once established in the wild.

Feeding

This plant does not require any supplemental fertilizer.

Pruning

Pruning is not recommended due to the risk of severe skin contact.

Repotting

This plant is not suitable for container gardening.

Soil

Versatile in most soil types

Soil pH

6.0 to 8.0

Temperature

-30 to 35°C

Humidity

30 to 80%

Safety

People

Contact with any part of the plant causes severe contact dermatitis in most people.

Pets

This plant contains urushiol, which causes severe skin irritation and allergic reactions in humans. Dogs and cats rarely develop a rash because their fur protects them, but they can carry the oil on their coat and pass it to people. Eating the plant may cause mild stomach upset in pets.

Children

Children should be taught to identify and avoid this plant entirely, as even minimal contact with stems or leaves causes severe irritation.

Contact allergens

The plant contains urushiol, a potent resin that causes painful, blistering rashes upon skin contact.

Airborne allergens

Burning the plant releases urushiol into the air, which can cause life threatening lung inflammation if inhaled.

Edibility

All parts of this plant are highly toxic if ingested and can cause severe internal reactions.

How to identify it

• Leaves of three leaflets
• Leaflets have smooth or notched edges
• Central leaflet has a longer stalk
• Hairy appearance on mature vines
• White or greenish berry clusters

Height

0.3 to 15m

Spread

0.3 to 10m

Leaves

green, red, orange, yellow, deciduous

Flowers

white, green, yellow, 0.2 to 0.5cm

Fruit

white, gray, Late summer to winter

Problems to watch for

• Leaf SpotCommon
• Powdery MildewCommon
• CaterpillarsUncommon
• RustUncommon

Growing it

Propagation

seed, rhizomes

When to plant

spring, fall

It is best to avoid planting this species entirely in managed landscapes due to its extreme toxicity.

Grows well with

• Virginia Creeper · They often grow together in the same woodland habitats.

Similar species

• Virginia Creeper · It is often mistaken for poison ivy but has five leaflets instead of three.

Science

Family

Anacardiaceae

Genus

Toxicodendron

Order

Sapindales

Class

Magnoliopsida

Native range

North America

Conservation

This plant is a common native species and is not of conservation concern.

It thrives in disturbed areas and forest edges, often outcompeting other plants by climbing trees to reach sunlight.

Value to wildlife

nectar source, winter food for birds, nesting material

Pollinators

bees, butterflies, beetles

Uses

wildlife habitat, erosion control

Taxonomy resolved against GBIF.

Questions people ask

Will my dog get a rash?

Dogs are generally protected by their fur, but they can carry the oil on their coat and transfer it to you.

How do I kill it?

Manual removal is difficult and risky, so systemic herbicides are often used by professionals.

Where the name comes from

The name Toxicodendron comes from the Greek words for poison and tree, while radicans refers to its rooting stems.

Good to know

• Poison ivy is not a true ivy but a member of the cashew family.
• The plant can grow as a ground cover, a shrub, or a high climbing vine.
• Urushiol oil is so potent that only a microscopic amount is needed to trigger a reaction.
• Birds eat the berries and disperse the seeds without being affected by the toxins.

Also in

• Plants toxic to cats and dogs