At night they typically aren't active. What I did in a similar situation was to get a heavy duty garbage bag and place it carefully and quickly around the nest. The I gathered the top of the bag around the attachment point of the nest and pulled the nest free so it dropped inside the sealed bag. Then I went outside and stomped on the bag. Cruel, but effective.

If you try this, have someone come with you to hold a flash light to insure they aren't entering or leaving the nest, and so you have your hands free to do the dirty work.

Wow, really? That sounds like a risky method. Are they really that sleepy at night? Do you think they'd be sleepy enough for me to carry the potting bench outside the GH? If I could do that, the rest would be easy. I can't use your method in-situ because the nest is tucked in under the shelf, and is not easily reachable. But if I could move the bench outside, then I could tip it on its side and have easy access.

Thanks for the suggestion!

OK, I think I can do that. In the meantime I read about a simple trap made from a soda bottle. I'll put that in there today and maybe I can catch a few before I try moving the bench. Thanks for the info!

Be careful. Personally I would just zap them with raid and be done with it. Unless the plants are in the way. When I used raid last year, it damaged some plants that got a little spray on them.

From someone who collected thousands of wasp nests to sell to a lab for anti-venom production, the best solutions are 1- raid , 2- co2 fire extinguisher. just blast with either. The wasps will all be on the nest at night so is the best time to get all. Jim

I often have those reddish brown wasps build nest in my work area and they have never stung me even after I bumped into them over and over again not knowing they were there. All the other types of wasps get irritated far easier but the reddish ones I leave alone - they eat a lot of caterpillars.

A strong jet from the garden hose will knock them down off the nest and spraying them with soapy water will keep them from flying. Getting rid of the nest will usually get rid of the colony but they may just come back and re-build.

Wasps have been dispatched, sorry wasps. DH did it this morning by just knocking the nest into a cardboard box and bringing the box outside. The wasps were sleepy and they barely stirred, DH reported. (DH was also sleepy as he did it immediately upon getting out of bed, before coffee! Heroic!)

Gosh, I would hope to never have to resort to Raid inside the GH that supplies so much of our food. Luckily it did not come to that. Now I will keep a closer eye on new nests so that we can catch them early and avoid chemicals.

Thanks again for the advice! I can go back to cleaning the GH now that the wasps are gone...

DH gets a medal! That was brave! Good for him. Have fun cleaning.