wetland wildflower
Canadian milkvetch
Astragalus canadensis
Also known as Canada Milkvetch, Milk Vetch
1 of 3Native to most of the USA and southern Canada
Southwestern Quebec to Hudson Bay and British Columbia, south to Georgia mountains, Texas, southwestern Utah and northern California
- Light Full sun to part shade Sun tolerance
- Moisture Dry to wet Moisture preference
- Zones 2–9 Cold to heat range
- Bloom May–Jul Flowering time
- Height up to 4 ft to 1.2 m
- Life cycle Perennial Annual to perennial
In the garden
A wetland wildflower for full sun to part shade and wet soil. At up to 4 ft, it suits rain gardens, pond edges, and damp low spots. Hardy in USDA zones 2–9.
Growing conditions
Light
Full sun Partial shade Full shade
Moisture
Dry Moist Wet
Hardiness zones
Find your zone:
Pollinators & wildlife
- Bees Common Eastern Bumble Bee
also Western Honey Bee, Eastern Carpenter Bee, Brown-belted Bumble Bee +30 more
Two-spotted Bumble Bee, American Bumble Bee, Ligated Furrow Bee, Tricolored Bumble Bee, Black-tailed Bumble Bee, Bombus fervidus, Red-belted Bumble Bee, Hunt's Bumble Bee, Two-spotted Longhorn Bee, Fuzzy-Horned Bumble Bee, Black-and-gold Bumble Bee, Yellow-fronted Bumble Bee, Agapostemon texanus, Northern Amber Bumble Bee, Nevada Bumble Bee, Sculptured Resin Bee, Great Basin Bumble Bee, Indiscriminate Cuckoo Bumble Bee, Southern Plains Bumble Bee, White-shouldered Bumble Bee, Parallel-striped Sweat Bee, Colletes simulans, Patchwork Leafcutter Bee, Golden-belted Bumble Bee, Illinois Sweat Bee, Anthidium psoraleae, Band-footed Sweat Bee, Colourful Willow Miner Bee, Coelioxys alternata, Bombus sp. - Flower flies Band-winged Bee Fly also Broad-headed Marsh Fly, Hairy-eyed Flower Fly, White-haired Pithead
- Beetles Onthophagus pennsylvanicus
- Also visited by
- Moths: Boneset Borer Moth
Butterflies that use this plant
Documented host and nectar records. Each links to a planting guide for that butterfly.
- Acmon bluecaterpillar host
- Marine bluecaterpillar host
- Melissa bluecaterpillar host
- Orange sulphurcaterpillar host
- Silvery bluecaterpillar host
Full plant details
Where it grows
- Habitat
- WetlandThe wild plant community it grows in.
- Native range
- Most of the USA and southern CanadaUnited States (42): AL, AR, CA, CO, CT, DC, GA, IA, ID, IL, IN, KS, KY, LA, MD, MI, MN, MO, MS, MT, NC, ND, NE, NJ, NM, NV, NY, OH, OK, OR, PA, SC, SD, TN, TX, UT, VA, VT, WA, WI, WV, WY. Canada (7): AB, BC, MB, NT, ON, QC, SK. Where it grows wild on its own, by state and province.
- Native distribution
- Southwestern Quebec to Hudson Bay and British Columbia, south to Georgia mountains, Texas, southwestern Utah and northern CaliforniaThe same native range, usually more exact than the state list, and often noting where it has spread beyond it.
Growing conditions
- Light
- Full sun to part shadeHow much sun it takes, from full sun to full shade.
- Moisture
- Dry to wetThe soil dampness it prefers, from dry to wet.
- Hardiness zones
- USDA 2–9 · Canadian 1–7The cold-to-heat climate range it survives.
- Soil
- Moist to mesic soilsThe soils it grows in naturally.
- Soil texture
- Light to medium (sandy to loamy)The soil grade it prefers, from sand to clay.
- Soil pH
- 6.0–8.0The acidity to alkalinity it tolerates (7 is neutral).
- Soil quality
- MediumHow rich a soil it needs. Many natives prefer lean soil and flop in rich beds.
- Water use
- MediumHow thirsty it is, a rough guide to how often to water.
- Salinity tolerance
- NoneHow well it copes with salty soil, near roads or the coast.
- Lime (CaCO₃) tolerance
- LowHow well it copes with chalky, lime-rich soil.
Growth & form
- Height
- up to 4 ft (to 1.2 m)Typical mature height.
- Life cycle
- PerennialWhether it lives a single season (annual), two (biennial), or returns for years (perennial).
- Growth rate
- ModerateA relative ranking versus other plants of the same type (USDA), not an absolute rate.
- Shape
- ProstrateIts overall silhouette.
- Root depth
- 10+ in (25+ cm)How far the roots reach, a guide to drought resilience and transplanting.
Flowers, foliage & fruit
- Type
- WildflowerWhat kind of plant it is.
- Bloom
- May–JulWhen it flowers.
- Flower color
- WhiteThe bloom color, or colors.
- Toxicity
- None knownWhether any part is poisonous to people or pets.
Propagation & seed
- Cold stratification
- Not requiredWhether seed needs a cold, moist spell before it will germinate.
- Propagation
- SeedHow to start new plants.
- Seed
- ~0.3 million seeds per poundNotes on the seed and how to sow it.
- Seed spread rate
- SlowHow readily it self-sows. Slow or none means well-behaved, not a spreader.
- Seedling vigor
- MediumHow strongly young seedlings establish.
- Vegetative spread
- SlowWhether it creeps outward or stays put in a clump.