This is the season for wasps in the garden. Most of these wasps are not aggressive and will not sting people if they are not provoked, which is good news. The other good news is that some of the wasps you see are providing pest-control services in your organic garden.
Larvae of the Blue Winged Digger Wasp eat beetle grubs. If you have a problem with Japanese beetles, for instance, tearing up your flowers and making lace out of the leaves of your favorite plants, then this wasp is your friend.
According to Penn State Extension, the adult female tunnels underground searching for beetle grubs, and when she finds one, she stings it, hauls it deeper underground, and then lays an egg on it. When the egg hatches, the baby wasp eats the grub.
Okay, so it’s a little gruesome, but this natural control for Japanese beetles requires no action on your part other than just letting the wasps do their good work.
The other helper-wasp that I’ve seen this week is the Potter Wasp. Similar to mud daubers, the adult female will build a little “clay pot” in which to lay an egg. Eileen Linton of the Master Gardeners of Galveston County explains that the wasp will hunt for caterpillars to sting and tuck inside the pot, and the baby wasp (larva), when it hatches, will dine on the caterpillars.
Like the Blue Winged Digger wasp, the adult Potter Wasps sip nectar from flowers, and as they fly from flower to flower in the garden, they act as pollinators. This is another way that both of these wasps are garden helpers.
I am kind of hoping that the Potter Wasps I’ve seen are not feeding my Monarch Butterfly caterpillars to their babies, but my garden is home to many other caterpillars, and some trees in the neighborhood have nests full of fall webworms. There are plenty of other caterpillars to feed baby wasps than the Monarchs!
Have you seen these helpers in your garden?