First, what an inventive way to foil the cutworms! I'm admiring & laughing at the same time.

What I want to know is how you managed not to get stung or pricked yourself whilst performing these delicate operations especially prying them open & putting them around the stems of the tomatoes.

well I know I am too clutzy to pull this off

I'd like to know that too, but I'm thinking a pair of disposable gloves might be the answer. Either that or two pairs of hemostats, one for each hand - Nah! I'd still get stung.

I'd also like to know how to fasten the nettle stems around the plants. How about a picture of the finished project?

Did the cut worms get stung or stuck on the nettles? Or do you think the nettles are a natural repellent/deterent to the cut worms? I realize the nettles will sting you and maybe the cut worm does too? I wonder if the nettle plants "scent" tricked the cut worm into thinking there wasnt a tomatoe plant? Or that it wouldn't risk injury trying to get to the tomato?
So my question is: Could you take the nettle plant, make a slurry in a blender, strain it and spray the stalk of your tomatoes/leaves so the cut worms wouldnt bite. What other pests would be deterred, slugs? Would spraying the juice around tomatoes on the soil in the evening send those cut worms running? Maybe earthworms wouldn't like that either!
I think your idea was marvelous. It made me wonder about other possibilities. I'd love to hear if you try any experiments with it in the future. And I'm really glad you saved your tomatoes!

You could try crushed eggshells, sprinkle them around the base of your plants. They wont go over them, it cuts them up.
I've not tried this, just read it somewhere, but worth a try!

My summer squash plants were blooming one morning the plants were cut off level with the soil. Do anyone know if that could be cut worms or something else?

I have used the eggshells and it worked. I "planted" larger pieces in the ground in a circle around the plants then sprinkled more for good measure. I replenished every few weeks.

I like the idea of using nature to solve problems. I wonder if soaking a paper towel in lemon juice could be effective? I would put plastic against the tomato to not burn it.

With my tomato plants I wrap the stem of each new seedling when I plant them with pieces of light fabric, Remay Cloth, netting, etc. With my pole string beans I sink a yogurt cup with the bottom cut out and plant two seeds in each one. This really helps against slugs as well. They don't seem interested in climbing into the cup!

Here are solution...in water to put shreds of hot pepper and a few drops of lemon, leave for about an hour ... Spray the plant...it is not toxic but effective .
Or mix of avaunt and calypso (for the plants we don't use in feeding).