California Landscape Design

While watering my garden when I noticed some small, gray-brown forms on a twig of a new hypericum bush. The branch looked dead and I was thinking of pruning it off. I looked closer and saw what appeared to be tiny pots—formed as if with a tiny potters wheel—glued to the stem of my new plant. I wondered how on earth they had gotten there, or what kind of creature had put them there.

As I poked around and snapped a few pictures there was a small, dark mud dauber-looking wasp circling around in the alstroemerias nearby. Wondering if this was the insect connected to the small structures, I took a step back and watched as she hovered closer to the Hypericum bush. She seemed to be carrying something. I watched closely and she flew up to the top clay pot-looking structure—the only one that didn’t have the top sealed over—and she put a wiggly little grub worm into the hole. What the heck was going on here?

And so, of course, I turned to Google. What I quickly identified was a Potter wasp, Eumeninae. Possibly Eumenes fraternus, but I'm not sure they are supposed to live in my area.

They are a species of beneficial insects—similar to mason bees—sometimes called a Mason wasp. They are totally non-aggressive, as I found with the one circling in my alstroemerias waiting for me to move always from her brood structures (the correct name for the tiny pots on my Hypericum stem).

It turns out the Potter bee (or wasp) helps the garden by collecting and caterpillar grubs and larvae that would otherwise eat our veggies and flowers and uses them to create a food supply for her larvae. Paralyzed and sealed inside her perfect little brood nest pottery structure.

It is the female potter bees that make these perfect little earthen structures. They tend to be loners, not having a hive mentality.

Looking at pictures online made me feel most impressed with our garden buddy’s fine-tuned skill. This potter bee made such perfect, smooth little pots the ones online looked coarse and chunky by comparison…maybe she likes my soil. 

Despite my sensitivity to bees, I decided not to prune away the stem. The momma bee came back and created and sealed a fourth brood chamber. The scientific name being from the Latin root Eumenes, meaning “well-disposed, friendly, and gracious”, I can hope her offspring are as docile as she is and they will be welcome beneficial predator in my garden for seasons to come.

I planted the Hypericum berries to experiment with the success of a new plant varieties that are bring modern cutting gardens into our home gardens, and by accident I learned they create habitat for beneficial garden insects, talented ones at that!