White trillium
Trillium grandiflorum · Melanthiaceae
Three leaves, three petals: large, pure white flowers that age to pink, held above a whorl of broad leaves in spring. It takes years to flower from seed, and lives for decades.
- Size
- 16 in tall, 12 in wide
- Zones
- 4 to 8
- Light
- Part shade to shade
- Flowers
- Mid April to mid May
- Pets
- Toxic to people
- Job in a bed
- Drift
A bed built around white trillium
The planner designed this bed around white trillium when this page was made: a 12 × 6 ft (3.7 × 1.8 m) naturalistic planting in zone 6, part shade. It chose the other plants from the 513 that suit those conditions, and says below why white trillium stands where it does.
The plants
- 1 White trillium × 8, white
- 2 Green-and-gold × 15, yellow
- 3 Dwarf goat's beard × 7, cream
- 4 Gray's sedge × 3, green
- 5 Log fern × 3, dark green leaves
- 6 Mountain hydrangea 'Tuff Stuff' × 1, pink
- 7 Giant snowdrop × 10, white
- 8 Hardy cyclamen × 5, pink
Why this plant
- The only open bowls. The others are daisies, plumes, globes and others. Shape reads at a distance, where colours blur.
Why here
- In the middle. At 16 in it stands ahead of log fern (3½ ft) without hiding it.
- A step in the back row. Next to log fern (3½ ft) and mountain hydrangea 'Tuff Stuff' (2½ ft): no two neighbours there are the same height, so the back steps up and down like a skyline.
- 8 plants in one group. Massed, one kind reads as a single shape. Scattered, it would look spotty.
Why now
- In flower for five weeks. From mid April to mid May.
- Fills a gap. For one of those weeks nothing else on the plan is in flower.
- Leaves gone by midsummer. They die back and leave bare ground. A perennial that comes up late stands beside it, and grows over the gap.
Planned as a naturalistic planting: low grasses and groundcovers, the matrix, make up 43% of the planted ground. The most in flower at one time is 3 kinds, from late May. The scheme leans cool (pink) and uses yellow for warmth, with white, cream and green to calm things between them.
The planner's own design check: 11 Excellent, 5 Good, 1 Satisfactory. It flags one thing to watch: Nothing on this plan is highly poisonous or an aggressive spreader.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where white trillium goes in a border
At 16 in it belongs at the front of a bed. In the planner's ten height classes it is short (12 to 18 in).
Its job: drift. Planted in a small group of three or five, and repeated further along in the other number.
Buy only nursery-propagated plants; wild-dug trilliums rarely survive, and collecting is destroying wild colonies. Leave the leaves until they die back, and never pick the flower with its leaves.
- The showpiece of a native woodland garden
- Under deciduous trees
- Long-lived spring colour
What to plant with white trillium
Plants recorded as good partners for it, and what each pairing does:
- Christmas fern: its dark green leaves are a setting for the flowers, before and after.
- Wild ginger: its green leaves are a setting for the flowers, before and after; bold leaves against its medium ones; low enough (6 in) to stand in front of it.
- Foamflower: in flower together for four weeks, from late April; happy in the same moist soil.
Questions about white trillium
Does white trillium need sun or shade?
White trillium grows in part shade (2 to 4 hours of sun, mostly in the morning) and shade (less than 2 hours of direct sun, or bright dappled light).
It wants soil that stays evenly moist, rich in organic matter, and a good soak in dry spells.
What zones does white trillium grow in?
USDA zones 4 to 8. It is hardy to zone 4, which means it survives winter nights down to about −20 °F (−29 °C).
Above zone 8 it struggles: the zones measure winter cold, but a plant's top zone usually means the summers are too hot or the winters too mild for it to rest.
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
When does white trillium flower in my zone?
In zone 5 it flowers mid April to mid May. As a spring flower it moves about a week for every zone: earlier where it is warmer, later where it is colder.
| Zone 4 | Late April to late May |
|---|---|
| Zone 5 | Mid April to mid May |
| Zone 6 | Mid April to early May |
| Zone 7 | Early April to early May |
| Zone 8 | Late March to late April |
Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.
How far apart should white trillium be planted?
12 in (30 cm) apart, from the middle of one plant to the middle of the next. That is about its full width, so each plant keeps its own outline.
It grows 16 in (40 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many white trillium plants do I need?
At 12 in apart, set out in staggered rows:
- 12 to fill 10 square feet (about 1 m²)
- 11 for a single row 10 ft (3 m) long
- 38 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as a group of three or five, with a second group further along in the other number.
In the bed above, the planner used eight in one group.
Is white trillium poisonous?
Yes: mild toxicity to people. May cause mild stomach upset if eaten.
Rated from NC State Extension. Where references disagree, the more cautious rating is used.
Do deer eat white trillium?
They may. NC State does not list it as resistant to deer or rabbits. Where they visit, protect it, or plant it among ones they avoid.
What flowers after white trillium?
White trillium is over by mid May. These start as it finishes and carry the same spot on, so it never goes flat:
- Sweet woodruff: from early May to early June, 8 in tall, to stand in front of it and cover its fading stems.
- Lady's mantle: from late May to early July, 18 in tall.
- Columbine: from early May to mid June, 24 in tall.
What does white trillium look like in winter?
White trillium has long gone by winter: it dies down in summer, soon after flowering, and comes back in spring.
Is white trillium good for bees and butterflies?
White trillium is visited by pollinators, bees and moths.
It is a host plant: the caterpillars of black-patched clepsis and american angle shades feed on its leaves. A butterfly can only lay its eggs on its host plants, so these do more for it than any nectar flower.
It is native to the United States and Canada.
More Trillium
- Red trillium Trillium erectum
In these guides
- Native perennials for pollinators
- Native plants for shade
- Garden plants native to Canada
- Plants for butterflies
- Plants for bees
- Plants for a white garden
Every fact on record
- Type
- Perennial
- Size
- 16 in (40 cm) tall, 12 in (30 cm) wide
- Plant
- 12 in (30 cm) apart
- Height class
- Short (12 to 18 in)
- Place in the bed
- Front
- Flowers
- Mid April to mid May; open bowls; white
- Leaves
- Medium texture, summer-dormant; green
- Shape
- Upright, clumping
- Hardy in
- USDA zones 4 to 8
- Light
- Part shade, shade
- Soil
- Rich, evenly moist
- Water
- Moderate
- Feeding
- Light, in spring
- Family
- Melanthiaceae
- Comes from
- Eastern North America
- Attracts
- Pollinators, bees, moths
- Host plant for
- Black-patched clepsis, American angle shades
Checked against NC State Extension. Flowering times are for zone 5: later in colder zones, earlier in warmer ones. Toxicity and spread information is a general gardening guide, not veterinary or medical advice, and invasive status varies by region. If a person or pet eats a plant, contact poison control or a vet. Check your local invasive species list before planting anything with a spread warning.