Asclepias Hirtella
Tall Green Milkweed for Monarch Caterpillars
Asclepias hirtella common names: Green milkweed, Hirtella milkweed, Prairie milkweed, Tall green milkweed
Tall Green Milkweed Plant Specs
- Perennial Zone: USDA hardiness zones 4-9 (lows -34.4 °C or -30 °F)
- Native Plant Range Map: Central US and Eastern Canada ( Al, Ar, Ga, Il, In, Ia, Ks, Ky, La, Mi, Mn, Ms, Mo, Oh, Ok, Tn, WV, Wi, ON)
- Full sun to part shade
- Height: 3-4 feet tall
- Spacing: 1 to 2 ft
- Flowers: umbels of greenish-white blooms, with tinges of purple
- Foliage: herbaceous perennial with thin leaves similar to swamp milkweed, but thicker than whorled milkweed
- Green stem with pairs with alternate leaves (not opposite like most milkweeds)
- Blooms during summer months (June, July, August)
Asclepias Hirtella Pros
- Easy to control spread in a garden setting
- Larval host plant for monarch caterpillars
- Butterflies and other pollinators use as a nectar source, including monarch butterfly
- fragrant flowers
- True prairie species that can withstand dry weather conditions
- Easy to start from milkweed seeds
Asclepias Hirtella Cons
- Does not thrive in overly moist soil
- Seeding can be a problem unless you take actions listed below
- Prone to aphid pests like most milkweed
- Does not transplant well because of long taproot
Asclepias Hirtella Plant Propagation
- Sow seeds directly outside in fall– November is a good option for most regions
- Start seeds indoors 2 months before final frost using cold moist stratification
- Try water stratification if cold stratification isn’t possible
- Spring Sow seeds directly after final frost
- Winter sowing is a good option if you want to control plant placement in early spring
Tall Green Milkweed Growing Tips
- Easiest to fall or winter sow
- Grow milkweed in sun to partial shade
- Can thrive in dry sandy conditions, as its used to prairie habitat but adaptable to other well-drained soil conditions
- Separate ‘prairie’ from other plants with more aggressive root growth like common milkweed
- Cut I- If you don’t want additional seedlings next spring, simply cut off all/some of the seed pods before they pop open or cover them with organza bags if you want to collect prairie milkweed seeds
Pollinator Plus: Attract More Pollinators
Prairie milkweed also attracts bumblebees, honey bees, various butterflies, moths, hummingbirds, other pollinators and beneficial insects
Buy Asclepias Hirtella Plants and Seeds
Always purchase seeds and plants by botanical (scientific) name. One of Asclepias hirtella’s common names, prairie milkweed, is also used to refer to other milkweed species:
- Buy Tall Green Milkweed Plants or Seeds from Joyful Butterfly
- Find Tall Green Milkweed on Etsy
- Buy Asclepias Hirtella Milkweed Seeds on eBay
Click here for 30 Milkweed Ideas for your Butterfly Garden
Asclepias Hirtella FAQs
Will Asclepias hirtella come back?
Prairie milkweed is a perennial milkweed species in USDA hardiness zones 4-9, so it should come back in those areas.
Why is Asclepias hirtella listed as a rare milkweed species?
In its northern range, states (including Minnesota) are losing native habitat at an alarming rate due to farmland being utilized for agricultural purposes. Herbicides are killing off once-abundant milkweed species like tall green milkweed.
Should Asclepias hirtella be deadheaded?
This milkweed species can be deadheadedto encourage a second round of flowering, but keep in mind this will mean less seed production if you plan to harvest milkweed seeds
Why Asclepias hirtella not flowering?
The most likely reasons your prairie milkweed isn’t blooming are due to too much nitrogen in the soil or insufficient sunlight.