Yes, adult psyllids have wings and are capable of flight, which allows them to move between plants.

Why is there black stuff on my leaves?

That is likely sooty mold, a fungus that grows on the sticky honeydew excreted by the psyllids as they feed.

Can psyllids kill my plant?

While they rarely kill established plants quickly, a heavy infestation can severely weaken them, making them vulnerable to other stresses.

Psyllids

Symptoms by part

Leaves

Leaves often curl, yellow, or develop small pits and galls. You might also see a sticky residue called honeydew or a black, sooty mold growing on the surface.

Stems

Stems may show stunted, twisted growth or abnormal swelling where the insects have fed.

Causes

Warm, dry weather conditions that favor rapid insect reproduction.
Introduction of infested plant material into your garden.
Presence of succulent, new growth which is highly attractive to adult psyllids.

Could be confused with

Aphids · Aphids are soft bodied and slow moving, whereas psyllids are more active and jump when disturbed.
Whiteflies · Whiteflies are moth like and fly up in a cloud when disturbed, while psyllids remain more stationary on the plant.

Treatment

1. Use a strong stream of water from a garden hose to blast the insects off the leaves and stems early in the day.
2. Prune away and dispose of heavily infested or severely distorted branches to reduce the population.
3. Apply fatty acids directly to the insects on the undersides of leaves, ensuring full coverage, follow the label.
4. Apply spinosad to the affected foliage if the infestation persists, follow the label.

Without chemicals

Prune out and destroy infested plant parts.
Encourage natural predators like ladybugs and lacewings in your garden.
Use fine mesh netting to cover susceptible plants during peak activity periods.

Chemical options

Fatty acids, spray directly on the insects, follow the label.
Spinosad, apply to foliage, follow the label.

Preventing it

Inspect new plants thoroughly for signs of curling or honeydew before bringing them home.
Avoid over fertilizing with nitrogen, which creates soft growth that attracts psyllids.
Keep plants well watered to help them withstand feeding pressure.

Season

The warm growing season.

Spread risk

Moderate

Severity

Moderate

When to act

Act as soon as you notice leaf curling or the presence of honeydew. If the plant becomes severely stunted or fails to thrive after treatment, it is best to remove and replace it.

Think it's Psyllids?

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Questions people ask

Do psyllids fly?: Yes, adult psyllids have wings and are capable of flight, which allows them to move between plants.
Why is there black stuff on my leaves?: That is likely sooty mold, a fungus that grows on the sticky honeydew excreted by the psyllids as they feed.
Can psyllids kill my plant?: While they rarely kill established plants quickly, a heavy infestation can severely weaken them, making them vulnerable to other stresses.

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This guide was generated with AI and is general information, not horticultural advice. Read about how we build these guides.