Saw greenbrier.

At a glance

Care level

Easy

Plant type

Perennial vine

Light

Full sun to partial shade

Indoor light

Bright indirect

Water

Every 7 to 14 days

Mature size

20 to 30 feet

Growth rate

Fast

Hardiness

USDA 6 to 10

Bloom time

Late spring to early summer

Care

This plant is very self sufficient and rarely needs human intervention. Watch for it spreading too aggressively into areas where you do not want it. It thrives in most soil conditions without extra help.

Watering

Water only during extended dry spells once the plant is established.

Feeding

Fertilizing is generally unnecessary for this vigorous native vine.

Pruning

Prune back annually in late winter if you need to control its size or spread.

Repotting

If growing in a container, move to a larger pot every few years when roots become crowded.

Soil

Well draining loam or clay

Soil pH

6.0 to 7.5

Temperature

-15 to 35°C

Humidity

40 to 80%

Safety

People

The plant is generally considered non-toxic, though the thorns can cause significant mechanical injury.

Children

Keep children away from this plant because the sharp, woody thorns can easily scratch or pierce skin.

Contact allergens

The sharp thorns can cause skin punctures and irritation.

Airborne allergens

The pollen may cause mild seasonal allergies in sensitive individuals.

Edibility

While the young shoots are edible, mature leaves and stems are tough and not recommended for consumption.

How to identify it

• Heart shaped leaves with white mottling
• Stems armed with sharp prickles
• Small greenish flowers in clusters
• Dark blue to black berries
• Strong tendrils for climbing

Height

3 to 6m

Spread

2 to 5m

Leaves

green, variegated, semi-evergreen

Flowers

greenish-yellow, 0.5 to 1cm

Fruit

black, Autumn

Problems to watch for

• Leaf SpotCommon
• CaterpillarsUncommon
• Powdery MildewUncommon
• RustUncommon

Growing it

Propagation

seed, division, cuttings

When to plant

spring, autumn

Plant this species only where you want a permanent, impenetrable thicket, as it is difficult to remove once established.

Grows well with

• American Beautyberry · They share similar woodland edge habitat requirements.
• Eastern Red Cedar · It provides a sturdy structure for the vine to climb.

Similar species

• Catbrier · It shares a similar growth habit and thorny stems.

Science

Family

Smilacaceae

Genus

Smilax

Order

Liliales

Class

Liliopsida

Native range

Southeastern and south-central United States.

Conservation

This species is common and widespread throughout its native range and is not of conservation concern.

It thrives in disturbed areas and forest edges where it uses its tendrils to climb over other vegetation for sunlight.

Value to wildlife

nectar source, nesting cover, bird food

Pollinators

bees, butterflies

Uses

natural fencing, wildlife habitat, erosion control

Taxonomy resolved against GBIF.

Questions people ask

Is this plant invasive?

It can be aggressive in garden settings due to its rapid growth and thorny nature.

How do I control it?

Regular pruning and digging out the root crown are necessary to keep it in check.

Where the name comes from

The genus name Smilax comes from the Greek word for a climbing plant, while bona-nox is Latin for good night.

Good to know

• The stems are extremely tough and were historically used for basketry.
• It is a vigorous climber that uses tendrils to scale trees and fences.
• The berries provide a vital winter food source for many bird species.
• It is highly resilient and can regrow from its root system after being cut back.