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flowerPerennial
Milkweed
Asclepias syriaca
Also known as: asclepias, butterfly flower, common milkweed
Essential host plant for monarch butterflies. Fragrant pink-purple flower clusters. Native perennial that spreads by rhizomes.
Growing Requirements
SunFull Sun
WaterLow
Soil Type
Soil Drainage
Soil pH
Plant Spacing18–24″
Row Spacing24–36″
Planting Depth0.25–0.5″
Height36–60″
Spread18–36″
✗ Not Container Friendly✗ Not Raised Bed Friendly
Planting Schedule
Start Indoors
8–10 weeks before last frost
Direct Sow (Spring)
0–9 weeks after last frost
Transplant Outdoors
0–9 weeks after last frost
Germination
10–21 days
Days to Harvest
120–365 days
Zone Suitability
USDA Hardiness Zones
1
2
3
4
5
6
7
8
9
10
11
12
13
Zones 3–9
Can overwinter in appropriate zones
Perennial in zones 3–9
Seeds need cold stratification (30 days). Spreads by rhizomes — give space. Milky sap is a skin irritant.
Companion Plants
No companion data available for this plant yet.