Leaf Holes

Leaf holes can be used to identify common garden pests and diseases.


Leaf holes can be caused by insects, disease, and chemical or physical damage. Many rose bush leaves exhibit holes caused by their own thorns. Wind whipped branches can also cause holes in leaves. In these cases, there’s really nothing you can do. Chemical damage is usually caused by herbicide overspray. Using chemical herbicides more carefully (or not at all) can prevent this from happening. The signs of pest and disease damage, however, can be used to fight back.


When a leaf has a hole in it, photosynthesis is reduced, the plant may be weakened, and it becomes more vulnerable to other pests and diseases. Use the information below to learn how to identify the cause of leaf holes in your garden or landscape plants.

Snail damage on salvia (Kate Russell)

Irregular holes

Irregularly shaped holes and complete defoliation, with the leaf midvein generally left intact are usually caused by:

• slugs and snails feeding at night - they leave a tell-tale slime trail; present year round
• cabbageworms - one inch green larva with pale yellow side stripes; feed during the day and leave brown droppings; present through the growing season
• cabbage loopers - one inch or larger green larva, move inchworm fashion; leave dark green droppings; usually present July and August
• hornworms - they can reach 3 to 4 inches in length and will devour small stems and entire leaves on members of the nightshade family (tomatoes, potatoes, eggplant, peppers)​

Flea beetle damage (Kate Russell)

Ragged edges & shot hole appearance

Pitting and small, irregular holes that merge to create raggedy areas are caused by flea beetles. Flea beetles are very small, only 1/16 to 1/8 of an inch long. They can be black, brown, bronze, bluish, or gray. Flea beetles are present throughout the growing season. If the holes look more similar to a shotgun blast, it is probably shot hole disease. Shot hole disease holes usually begin as 1/10 to 1/4 inch diameter red or purplish spots. There may be a pale green or yellow ring around each spot. As the dead tissue dries up and falls away, the shotgun blast look appears.

Spotted cucumber beetle leaf feeding (Melissa McMasters) CC BY 2.0

Irregular holes, chewed stems, leaf chlorosis (yellowing), and wilting

This recipe for disaster indicates the presence of cucumber beetles. Cucumber beetles can be striped or spotted and they nearly always cause significant plant damage.

Leaf miner damage on beet leaf (Kate Russell)

Opaque “windows”

Western avocado leafrollers (Amorbia cuneana), orange tortrix (Argyrotaenia citrana), and other leafroller larvae feed on single layers of leaf material, creating opaque windows that eventually dry up and fall out. These larvae are usually green and less than one inch long. Older larvae may start chewing through entire leaves, usually from the outer edge and working their way inward. Windows may also be caused by fungal diseases and leaf miners.
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Oval or angular lesions

Anthracnose fungi can cause circular or angular brown spots on leaves and sunken oval lesions on large leaf veins. The browned areas turn white before falling out. Wilting of outer leaves is another symptom of anthracnose.

Anthracnose on tomato leaf (Scot Nelson) Public Domain

Leaf slits

If your grape leaves look as though a tiny, knife-wielding slasher attack occurred, it was probably the Western grape rootworm (Bromius obscurus). Leaf slits are usually 1/4 to 1/2 inch long. Individually, these slits are usually too small to seem important, but the combined effect can be devastating to the leaf. Damage is also seen in the berries.

Fuller rose beetle damage (Kate Russell)

Scalloped edges

If your lilac, rose, citrus, or avocado leaves have scalloped edges, it’s probably weevils. One adult weevil, the Fuller rose beetle, causes cosmetic damage on many different fruit and ornamental trees and shrubs. It is the underground larvae, however, that cause the real damage as they feed on roots. Other weevils, which tend to be long-nosed beetles, can cause damage both above and below the soil level.

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Once you identify the cause of holes in your leaves, you can select the best treatment. This list is by no means exclusive, but it should give you a good starting point. If you have other causes of leaf holes, please tell us in the comments below!