Pocket Botanist
Check these first
- Inspect the undersides of the leaves for aphids.
- Check if the soil stays wet for too long.
- Look for signs of mold or mildew on the foliage.
Likely causes
Fungal Leaf Spot
PossibleHow to tell: You will see small brown or black circles often with a yellow halo around them. These spots usually appear after long periods of rain or overhead watering.
What to do: Remove the affected leaves immediately to stop the spread. Water only at the base of the plant to keep the foliage dry.
Aphid Damage
PossibleHow to tell: Clusters of bright yellow or orange aphids leave behind sticky honeydew that can lead to sooty mold. Look for these bugs on the tender new growth at the top of the plant.
What to do: Spray the aphids off with a strong stream of water from your hose. You can also wipe them away with a damp cloth if the infestation is small.
Find out what's wrong with your milkweed
The list above covers the usual causes. Pocket Botanist looks at a photo of your actual plant and tells you the likely cause, how serious it is, and what to try first. Identification and a health check are free.
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When to worry
Worry if the spots are spreading rapidly across the whole plant. A few spots on older leaves at the bottom of the plant are usually fine.
Stopping it coming back
Ensure your milkweed has plenty of space for air to circulate between plants. Always water the soil directly rather than spraying the leaves.
Keep your milkweed healthy from here
Save your plant in Pocket Botanist and you get care reminders timed for this plant, plus a care history that shows what worked. Identification and a health check are free.
Questions people ask
- Should I use a fungicide?
- Usually no. Simply improving airflow and keeping the leaves dry is enough to stop the issue.
- Will these spots kill my plant?
- Rarely. Milkweed is quite tough and can usually outgrow minor leaf damage.
More problems with Milkweed
- Why are there bugs on my milkweed?
- Why is my milkweed growing tall and thin?
- Why are my milkweed leaves turning yellow?
- Why are my milkweed leaves getting brown tips?
- Why is my milkweed plant drooping?
- Why is my milkweed losing its leaves?
- Why is my milkweed not blooming?
- How do I fix root rot in my milkweed?
- Why are my milkweed leaves curling?
This article was generated with AI from the plant’s care profile and is general information, not horticultural advice. Read about how we build these guides.