Trilliums - Fascinating Flowers for a Woodland Garden

Trillium grandiflorum - Great White Trillium
Trillium grandiflorum is right at home in a woodland or woodland garden. Photo: © Marie Iannotti

Overview and Description

Trilliums are low growing woodland flowers. Most are native to the U.S. and you will often stumble upon a patch of trillium while walking in the woods. Different species favor different areas. Some are more showy than others, but what they all share are 3 leaves, 3 petals and 3 sepals.

Once established, trilliums are not difficult to grow. However they are particular about their growing conditions and can be very slow to reproduce.

 Trilliums spread by underground rhizomes and eventually can form a dense mat. During warm or dry summers, the plants may go dormant and die back to the ground.

Don't be tempted to take a plant from the wild. Many species are protected and some are endangered. Luckily more trilliums are finding their way into nurseries and catalogs.

Trillium are members of the lily family. Although they vary widely in height, form and color, they can all be identified by their 3 leaves and 3 flower petals.

  • Leaves: Leaves can be oval, elliptical, lance or diamond shaped, in solid green, mottled or with red veining. The meet in a point, on the stem, and whorl out around it.
  • Flowers: Each flower has three petals. The flowers can be tubular or cupped shaped and may be held erect on a stem or stemless.

Botanical Name

Trillium spp. and cvs.

Common Names

Trilliums, Wake Robin, Trinity Flower, Triplet Lily

Hardiness Zones

Hardiness will vary with the variety you are growing, but most trillium plants are reliably perennial in USDA Hardiness Zones 3 - 9.

Exposure

Trillium plants are woodland flowers and they do best in partial to full shade.

Mature Plant Size

The plants are low growing, reaching a mature height of about 12 - 15 inches (h) x 12 - 18 inches (w)

Bloom Period

Trilliums are early bloomers. Most varieties will put on their best show in mid-Spring

Suggested Varieties

  • Trillium grandiflorum, Great White Trillium - Showy white petals fade to pink, as they age. Nice for eastern U.S. Zones 4–7
  • Trillium erectum, Stinking Benjamin - The fragrance isn't sweet, but it's not strong. This is a tall Trillium with red or white flowers(var. album). Good for eastern and northern gardens. Zones 4–7/li>
  • Trillium vaseyi Sweet Beth - Almost 2' tall with 4" maroon flowers. Nice choice for southern gardeners. Zones 5–8/li>/li>/li>
  • Trillium chloropetalum - Giant Trillium - Very showy, with 7" long mottled leaves and flower colors from white to mahogany. West coast native, particularly the northwest. Zones 6–9

Design Suggestions

Trillium plants belong in a shaded woodland setting, where their quiet elegance commands attention. Plant them among ferns, gingers, columbines, Solomon's seal and spring blooming bulbs like scilla and cyclamen. They also make a nice front edge to a woodland walk, where you're sure to see and enjoy them while in bloom.

Don't plant them too close to shallow rooted trees and shrubs that will compete for moisture.

Start them in planting pockets enriched with humus and look for spots under deeper rooted trees, such as magnolias. Some of the smaller species are also suitable for alpine or rock gardens.

Trillium Growing Tips

Soil: Trillium plants prefer a neutral to slightly acidic soil pH. They also need a soil rich in organic matter that holds moisture well, much like they'd have growing wild on the forest floor.

Planting: Trilliums are usually started by division. The best time to divide or plant trillium is late summer to early fall. Be sure to mark the spot, so you'll look for them to emerge next spring.

You can start trillium from seed, but it's a slow process. It can take up to two years for the seed to germinate and up to another seven years for the flowers to bloom. This helps explain why you don't see more trillium for sale and why they cost so much.

Caring for Trillium Plants

Give them plenty of organic matter and water and your Trillium plants should take care of themselves. Leaf mold is the perfect side dressing for Trillium. Adding a light layer in spring, fall, and perhaps mid-summer is all the food they should need.

Pests & Problems of Trillium Plants

The biggest pest of trilliums is deer. They don't usually eat them all, but they will stop by for a light snack.