perennialN. America Native

Painted Trillium

The Story

Plant Bio

Trillium undulatum is an herbaceous woodland perennial that arises from a thick horizontal rhizome to form an unbranched stem topped by three maroon-infused leaves. In mid-spring, a single stalked flower opens directly above the foliage display, featuring three wavy white petals marked with a deep red-pink chevron at the base.

This species is distinguished from other trilliums by its striking V-shaped floral throat markings and strict requirement for cold, strongly acidic soils. Following pollination by native insects, the blooms form bright red berries in late summer before the foliage goes naturally dormant.

Uses & Benefits:

Striking white flowers with magenta throat markings stand out against dark woodland foliage.

Thrives in deep shade and strongly acidic soils where many ornamental perennials fail.

Provides early nectar for native bees and produces elaiosome-bearing seeds dispersed by ants.

Essentials

At a Glance

Plant Type

Perennial

Height

18"

Width

12"

Light

Partial Sun, Shade

Zones

4, 5, 6, 7, 8

Water

Medium to High

Humidity

Moderate to High

Lifespan

Perennial

Native To

North America

Toxicity

Toxic if ingested

Bloom period

Mid spring – Early summer

In flower about 3 months of the year

Planting

How to Grow

Select a deeply shaded site with cool, strongly acidic soil rich in leaf mold.
Plant dormant rhizomes two inches deep and oriented horizontally.
Water thoroughly after planting and maintain consistent moisture through spring and early summer.
Apply an annual top-dressing of shredded oak leaves or pine needles to maintain soil acidity and suppress weeds.

Pro Tip

Maintain a cool, strongly acidic root zone enriched with composted leaf mold, and never remove yellowing summer foliage prematurely while it is recharging the underground rhizome.

Keep It Thriving

Care Guide

Do

Keep soil consistently moist and rich in organic forest humus.
Mulch heavily with acidic leaf mold to keep soil cool.
Protect emerging spring foliage from deer browsing.

Don't

Do not plant in neutral or lime-rich alkaline soils.
Do not allow soil to dry out during the spring growing season.
Do not cut back foliage while leaves remain green.

Seasonal Care Calendar

Task	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Mulch
Pest Check
Plant
Propagate

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

Woodland GardenNative Shade BorderNaturalized Understory

Companion Plants

Cornus canadensis Gaultheria procumbens Polystichum acrostichoides Maianthemum canadense

Multiply

Propagation Methods

Good to Know

Common Questions

Painted Trillium questions

What zones can Painted Trillium grow in?

Painted Trillium is hardy in USDA Zones 4–8. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

Is Painted Trillium deer resistant?

Not reliably. Deer may browse Painted Trillium, especially tender spring growth — plan on repellents or fencing where pressure is high.

When does Painted Trillium bloom?

Painted Trillium typically blooms in mid spring through early summer. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does Painted Trillium need full sun?

Painted Trillium does best in part shade.