Native & adapted

Desert milkweed

Asclepias subulata

Leafless blue-green stems host monarch and queen butterflies and thrive in hot, open desert exposure.

Sonoran nativeButterfly hostPollinatorVery low water

Landscape layersUnderstory

Mature size

3–5 ft tall × 2–4 ft wide

Climate fit

Urban core · USDA 9b–10a · Valley suburbs · USDA 9a–9b · Desert outskirts · USDA 8b–9b

Special categories

SONORAN DESERT NATIVE · POLLINATOR ATTRACTING

Hardiness guidance

USDA zones 9–11; protect young plants from severe frost

Before you plant

These conditions determine whether it will thrive.

Cold hardiness

Cover while young

AMWUA rates it hardy to 20°F, so established plants are fine in Phoenix. Cover new plantings in their first winter if a hard freeze hits.

Leaves and wood: damaged below 20°F

Heat tolerance

Takes full sun and heat

Takes full and reflected sun. Too much shade makes it floppy and cuts flowering.

Sources:

amwua.org

Right plant, right place

Will Desert milkweed grow at your Arizona property?

A monarch and queen butterfly host rather than a generic nectar plant. Do not use systemic insecticides, and expect caterpillars to consume tissue.

Best regional fit: Urban core · USDA 9b–10a, Valley suburbs · USDA 9a–9b, Desert outskirts · USDA 8b–9b.

Light

Sun exposure

Full sun and intense heat.

Water

Irrigation

Very low once established. Brief deep irrigation during prolonged drought supports growth without creating soft, weak stems.

Choose the actual plant, not only the label

Cultivars & selections

Named cultivars are not the goal. Use locally propagated Asclepias subulata and avoid substituting tropical milkweed when building a Sonoran Desert host-plant system.

Local seed-grown desert milkweed

Asclepias subulata

Mature size3–5 ft tall × 2–4 ft wide

Best forNative monarch and queen butterfly habitat

Blue-green leafless stems are the normal mature form. Local seed provenance and pesticide-free production matter more than ornamental uniformity.

Planting & stewardship

How to help Desert milkweed thrive

1
Confirm the plant’s mature spread and underground conflicts before digging.
2
Place the root flare at finished grade and keep mulch away from the trunk.
3
Establish a wide, deep root zone instead of irrigating only at the trunk.
4
Observe seasonal growth, heat stress, and wildlife use before making major pruning changes.

Read the horticultural reference ↗