Last year I started some Coreopsis from seed. Being its perennial I knew I would have to wait until year two to see blooms but that was OK. I had seen the gorgeous blooms at the community garden and wanted them at home as well. Above are the blooms of the Coreopsis at the community garden. They are the perfect plant for a rock wall garden. This plant grows easily from seed and is hardy here.
Last week I had friends over and one of them spotted something nibbling on my Coreopsis plants. If you look closely at the photo above you can see holes and tears in the leaves. There were sign of excrement on the leaves. I knew that wasn’t a good sign.
My friend, Alex, spotted the bugs with his young eyes. They were tucked inside the buds having a great time. At first I thought they resembled lady bugs but we all know they have spots not stripes. I had to take a closer look.
I grabbed a small plastic container and started to hand-pick the beetle off the Coreopsis plants. That way I could get a good look at them. They have the same hard shell as a ladybug but each of these beetles had three distinct black stripes on them. The beetle is about 1/4″ long. So what could it be? They were only on the Coreopsis plants and no other plant nearby had them. I knew it was something specific to Coreopsis so my online search began.
This closeup was what I had to go with. Finally after a bit of sleuthing I found a short article by Linda Gilkeson with a photo of the beetle. It was the Coreopsis leaf beetle or Calligrapha californica coreopsivora. I wasn’t sure how to control them but being an organic gardener I started to hand-pick them off the plants daily. I squished them as I went. I know, poor things, but I wanted to see blooms after two years of waiting for the plants. I continued to do daily inspections and pick the beetles off. I see less and less of this pest and it looks like I will have flowers soon. Remember the flowers I showed you at the community garden? They do not have any beetles on them. The only difference between my planting and the community garden is theirs is more exposed to wind and full sun. My garden is quite protected and shaded from the hot afternoon sun. I guess my question is where did they come from? How do they overwinter and on what? I have learned that this adult beetle will lay eggs near the base of the plant so by picking off as many as I can hopefully it will disrupt the life cycle of this pest. I sure don’t want them back next year.
Wouldn’t you know the next week I started receiving emails from the master gardeners at VanDusen about this new pest. The Coreopsis leaf beetle had returned after a seven-year hiatus. This is common for many insects. Gardeners all over are reporting this beetle on their Coreopsis plants. So check your plants and hand-pick them off. Drop them into a bucket of soapy water to drown them. I actually tried this but found the beetles quite adaptable to the water so squishing became my method of control.
