Red trillium.

At a glance

Care level

Moderate

Plant type

Perennial

Light

Partial shade to full shade

Indoor light

Medium light

Water

Every 5 to 10 days

Mature size

12 to 18 inches

Growth rate

Slow

Hardiness

USDA 4 to 7

Bloom time

Mid to late spring

Care

Plant these in rich, moist, and well draining soil that mimics a woodland environment. Keep an eye out for slugs or snails, as they love to snack on the foliage. Ensure the soil stays consistently damp but never soggy to keep the rhizomes healthy.

Watering

Keep the soil consistently moist but never waterlogged.

Feeding

Apply a light layer of organic compost in early spring.

Pruning

Remove dead foliage only after the leaves have naturally yellowed.

Repotting

These plants prefer to stay undisturbed in the same spot for years.

Soil

Humus rich, moist, well draining soil

Soil pH

Slightly acidic to neutral

Temperature

-30 to 25°C

Humidity

50 to 80%

Safety

People

All parts of the plant contain saponins that can cause irritation if ingested.

Pets

This plant is not well studied in pets, but all parts contain saponins, so cats and dogs that chew the leaves, rhizome or berries may develop mild stomach upset such as vomiting or diarrhea.

Children

Keep children away from the berries, as they are toxic if ingested.

Contact allergens

The sap may cause mild skin irritation in sensitive individuals.

Airborne allergens

There are no notable respiratory allergens associated with this plant.

Edibility

The plant is considered toxic and should not be consumed.

How to identify it

• Three broad, diamond shaped leaves
• Single maroon or brownish red flower
• Flower petals curve slightly backward
• Stems grow directly from rhizomes

Height

0.2 to 0.4m

Spread

0.2 to 0.3m

Leaves

green, deciduous

Flowers

maroon, dark red, 3 to 6cm

Fruit

red, Late summer

Problems to watch for

• Slugs and snails · These pests often feed on the tender foliage in early spring.
• Fungal leaf spot · Occurs primarily in areas with poor air circulation and high humidity.

Growing it

Propagation

division, seed

When to plant

spring, fall

Plant in groups with other spring ephemerals to create a lush forest floor effect before the tree canopy fully leafs out.

Grows well with

• Wild Ginger · They share similar requirements for shade and moist, organic soil.
• Maidenhair Fern · The delicate fronds provide a beautiful textural contrast to the broad leaves.

Similar species

• White Trillium · It is a larger, more common relative with white flowers.
• Yellow Trillium · It features yellow flowers and mottled foliage.

Science

Family

Melanthiaceae

Genus

Trillium

Order

Liliales

Class

Liliopsida

Native range

Eastern North America

Conservation

Avoid purchasing wild-collected plants, as they are slow to recover and often poached from native habitats.

It thrives in the cool, moist, and nutrient-rich soils of deciduous forests.

Value to wildlife

nectar source, seed dispersal by ants

Pollinators

bees, beetles

Uses

woodland garden, shade border, native plant collection

Taxonomy resolved against GBIF.

Questions people ask

Does it need full sun?

No, it prefers deep to partial shade and will burn in direct sun.

How do I propagate it?

Division is easiest, but it must be done carefully while the plant is dormant.

Where the name comes from

The name Trillium refers to the plant's parts occurring in threes, while erectum describes the flower's upright position.

Good to know

• It is commonly known as the stinking Benjamin or wake robin.
• The seeds have a fleshy appendage called an elaiosome that attracts ants, which carry them to their nests.
• It takes several years for a seedling to reach flowering size.
• The plant goes dormant by midsummer, disappearing entirely from the forest floor.

Also in

• Plants toxic to cats and dogs
• Plants for shade