Troubleshooting
Green Milkweed problems — and how to fix them
Green Milkweed (Asclepias viridis) is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Oleander aphid (Aphis nerii)
Bright orange-yellow aphids are common on stem tips and young growth throughout summer. Hose off with water or apply insecticidal soap directly to colonies. Avoid broad-spectrum insecticides; Monarch caterpillars feed on the same plant.
Sluggish establishment from transplant
Like most milkweeds, A. viridis has a deep taproot and dislikes root disturbance. Plants may appear to do little the first season while establishing underground. Do not over-water or over-fertilise in an attempt to 'push' growth; patience is required.
Powdery mildew in humid conditions
White powdery fungal coating can appear on leaves in late summer when air circulation is poor. Improve spacing and avoid overhead watering. Rarely fatal to established plants; simply unsightly. Cut back affected foliage to encourage fresh growth.
Prevent green milkweed problems before they start
Most green milkweed issues are care-mismatch, not bad luck. Dial in the basics:
Looking for green milkweed in general rather than its problems? Read the full green milkweed care guide — light, water, soil and feeding.
Green Milkweed problems — FAQ
Why is my green milkweed oleander aphid (aphis nerii)?
Bright orange-yellow aphids are common on stem tips and young growth throughout summer. Hose off with water or apply insecticidal soap directly to colonies. Avoid broad-spectrum insecticides; Monarch caterpillars feed on the same plant.
Why is my green milkweed sluggish establishment from transplant?
Like most milkweeds, A. viridis has a deep taproot and dislikes root disturbance. Plants may appear to do little the first season while establishing underground. Do not over-water or over-fertilise in an attempt to 'push' growth; patience is required.
Why is my green milkweed powdery mildew in humid conditions?
White powdery fungal coating can appear on leaves in late summer when air circulation is poor. Improve spacing and avoid overhead watering. Rarely fatal to established plants; simply unsightly. Cut back affected foliage to encourage fresh growth.