Are you seeing damage on your bougainvillea leaves? Like something’s been chomping and munching away? I’m not talking little nibbles here and there but some serious feasting. I’ll tell and show you what it might be so you can identify the pest and take action.
I had 2 bougainvilleas in my Santa Barbara garden and 4 here in Tucson. I’ve learned a lot about them from working at a nursery but mostly by hands-on experience. They’re relatively easy to maintain except for the pruning which I happen to enjoy (yes, it’s true!) and you can’t beat them for an all-out show of color.
There are a few pests which attack them that I’ve skimmed over in previous bougainvillea posts and videos – so it’s time for more details.
Something eating my bougainvillea leaves! Hopefully, this will help:
3 Possible Pests Are the Culprits
Leaf Cutter Bee
This 1 is very easy to identify because you’ll see large even chomps, like half moons, taken out of the sides of the foliage. You rarely see the leaf cutter bee itself because it does its thing & then is gone. I never saw leaf cutter bees in Santa Barbara but I did have them on 1 of my bougies in the spring. Nothing too bad but enough for me to notice. It’s now the very end of August & low & behold, I found 1 leaf with the evidence so I could show you.
What you should do as treatment: Nothing. These bees are beneficial pollinators & we need them. The leaves will grow back & by the way, they can’t be bothered with us humans so you don’t have to worry about being stung.
Evidence of leaf cutter bees. My how neatly they eat!
The next 2 pests are caterpillars which mean they eat like crazy. There are so many different types of caterpillars & they’re all hungry critters. The damage done by caterpillars can vary a bit but the treatment is generally the same.
All caterpillars (not only this one) eat & poop like crazy so the little black specks you’ll see on the leaves is their frass. And yes, caterpillar excrement has it’s own word.
Head’s up: Those black droppings are a sign caterpillars are in the house!
These are the 2 which I have seen on my bougainvilleas & have experience with:
I didn’t see these on my bougies in Santa Barbara either. They protect by getting on the under the leaves, rolling themselves up & then closing the leaves with silk threads. After the caterpillars have gone, you can unroll a leaf & still see evidence of the threads on the undersides. The damage to the plant is mainly at the end of the stems, as far as I can see anyway.
The leaftier caterpillar. You can see the webbing, like threads of silk, on the leaf behind the caterpillar which I unrolled.
Here’s the damage done to the ends of the stems by the leaftier. You can see how 1 of the leaves is rolled up.
These are the most common chewing pests which attack bougainvilleas that I know of. My Bougainvillea glabra had them big time in Santa Barbara every year come late July. They’re inch worms & can be brown to green to yellow. The loopers are hard to spot because they hang out under the leaves & do their feeding at night.
To me, they damage they do a lot more damage then the leaftier. The leaves get chewed extensively, both old & new, & can ultimately look like thin lace or be gone all together. I’ve never seen the looper cause leaf curl – please let us know otherwise if you have.
Here’s what the bougainvillea looper looks like; basically a small green inchworm. In the video, you can see the damage done to my mint by the cabbage looper. It looks similar to the damage this looper does.
Treatment For These Caterpillars on Your Bougainvillea Leaves
Head’s up: These pests don’t do any harm to or endanger the health of an established plant. All the damage is cosmetic. Bougainvilleas shed & regrow foliage a couple of times a year so you’ll see new leaves appear. On the other hand, a young plant could be susceptible to a bad infestation.
Here are your three options for treating these bougainvillea pests:
My bougainvilleas are well established & the damage doesn’t bother me, with either caterpillar. They hatch into moths, fly away & then I won’t see them again for a year. That being said, I will eventually prune off the damage done by the leaftiers. I would let the loopers be because my glabra was so full & dense it was hard to see unless I got close up.Remove them by hand.
2.) Remove the Pests by Hand
This is much easier to do with the leaftier as you can find them covered in silk inside the rolled up leaves during the day. The looper is much harder to find so this would be extremely labor intensive.
If you choose to control them with a spray, my word of advise would be to do it early on before the infestation gets worse. Reapply if the caterpillars return. Be sure to spray where the caterpillars to make it effective. Even though both of these sprays are reported to be non-harmful to beneficial insects, please be sure to spray around dusk when they aren’t as active.
3.) Spray the Leaves
BT is a naturally occurring bacteria which makes the caterpillars sick & ultimately causes them to die. It’s considered to be a natural pesticide. When I worked at a nursery, this is what we always recommended to control caterpillars. The other product would be neem oil. It’s reported to control caterpillars though I have no experience with this. Please let us know if you have.
Head’s up: caterpillars are treated differently so insecticidal soap & horticultural oil wouldn’t be effective at all – don’t waste your time.
I’ve noticed that these pests don’t seem to attack the flowers and that’s a very good thing. We want that explosion of color that only bougainvillea leaves can provide! By the way, none of my other plants have been attacked by these pests. Whether you choose to treat or not, do a little more research to see what’s best for you, the plant and the environment.