Black Fly on Fig Trees: Treatment & Prevention

Quick Answer

Black fly, or black bean aphid (Aphis fabae), swarms the soft new shoot tips of fig trees in late spring, sucking sap so the tips curl and stop extending, and leaving sticky honeydew that draws ants and sooty mould. Clear it by pinching off the worst-colonised tips, blasting the rest off with a jet of water every few days, and using insecticidal soap or neem on stubborn colonies. Exclude ants with a trunk barrier so ladybirds and other predators can finish the job. It weakens growth but does not kill trees.

Black fly is the aphid you will meet most on figs, and it always goes for the same target: the tenderest new growth. It looks alarming when a shoot tip is black with them, but it is one of the more manageable pests once you know the routine.

What to Look For

The signs are hard to miss: dense black insect colonies massing on new shoot tips, shoot tips curling inward and failing to extend, sticky honeydew residue on leaves, and often trails of ants running up and down the trunk along with the black sooty mould that grows on the honeydew. The aphids concentrate on the softest, newest growth where the sap is easiest to reach.

What Causes It

Black bean aphid colonies build explosively on the flush of soft new growth in late spring and early summer. Warm weather and lush, nitrogen-rich new shoots are ideal for them, and they reproduce astonishingly fast. Ants accelerate the problem by protecting the colonies from predators in exchange for honeydew, which is why an ant barrier is part of the fix rather than a side note.

Is It Serious?

Not for an established tree. Black fly distorts and weakens new shoots and creates a sticky, sooty mess, but it will not kill a healthy fig. The main costs are cosmetic and a little lost vigour on the affected tips. On young or already-stressed trees it is worth staying on top of, since heavy infestations can noticeably slow growth.

My Treatment Plan

Pinch out or prune the worst tips. Removing the most heavily colonised shoot tips takes out a big share of the population instantly.
Blast them off with water. A strong jet dislodges colonies; repeat every few days to stay ahead of them.
Apply insecticidal soap or neem oil for stubborn colonies, covering leaf undersides and growing points well.
Encourage natural predators: ladybirds, lacewings, hoverflies, and parasitic wasps make quick work of aphids.
Put an ant barrier on the trunk so ants stop shielding the colonies from those predators.

⚠️ Go easy on the chemicals

Reach for water, soap, or neem before anything stronger. Broad-spectrum insecticides kill the ladybirds and parasitic wasps that control aphids naturally, and you can end up with worse outbreaks once those predators are gone.

Preventing It Next Season

Do not overdo nitrogen: lush, soft, over-fertilised growth is exactly what black fly loves, so a balanced feeding plan makes trees less attractive to them. Keep ant barriers on trees with a history of aphids, encourage a predator-friendly garden, and check new spring growth regularly so you can pinch out the first small colonies before they explode. My feeding guide covers keeping growth strong but not soft.

Not sure it’s black fly? Curling tips and honeydew overlap with mites and scale. Check your tree’s symptoms against all 18 conditions with the free interactive tool.

Run the Symptom Checker

Frequently Asked Questions

What are the black bugs clustered on my fig shoot tips?

Dense black insect colonies massing on soft new shoot tips are almost always black fly, also called black bean aphid (Aphis fabae). They cluster on the tenderest new growth to suck sap, causing shoot tips to curl and fail to extend, and they excrete sticky honeydew that draws ants and grows sooty mould.

How do I get rid of black fly on my fig tree?

Start by pinching out or pruning the most heavily colonised shoot tips, then blast the rest off with a strong jet of water, repeating every few days. For persistent colonies apply insecticidal soap or neem oil with good coverage of leaf undersides, and put an ant barrier on the trunk so ants stop protecting the aphids from predators.

Will black fly kill my fig tree?

No. Black fly weakens and distorts new growth and makes a sticky mess, but it does not kill established fig trees. The damage is mostly to soft new shoots and is largely cosmetic. Left completely unchecked on a young or weak tree, heavy infestations can slow growth, so it is still worth controlling.

Do I need to spray, or will ladybirds handle black fly?

Natural predators like ladybirds, lacewings, hoverflies, and parasitic wasps are very effective on aphids, and often you can let them do the work, especially if you first exclude the ants that defend the colonies. Reserve soap or neem sprays for heavy outbreaks, and choose them over broad-spectrum insecticides so you protect those beneficials.

Why do ants appear with black fly?

Like scale insects, black fly excretes sugary honeydew that ants harvest. In return the ants protect the aphid colonies from predators. Applying an ant barrier to the trunk removes that protection and lets ladybirds and other beneficials clear the aphids much faster.