Your 'Creeping Jenny' sounds like Glechoma hederacea, rather than Lysimachia nummularia, which is the plant generally known by that common name.

How many squash plants are we talking about? I guess I don't understand why you can't weed them "once it starts running"?

As far north as you are using the plastic shouldn't pose any problems like is does for those of us in the south and it does keep the ground fruit cleaner. But you will have to run irrigation lines under it as most of the water on top just runs off before it can leach through.

Other possible alternatives would be to grow the squash vertically as some do or use the straw and one of the spray on pest repellents made for rodents.

Dave

Play with the plastic. In the end you may or not like it but you won't know until you try it.

You are correct, floral-UK, it's Glechoma hederacea. My winter squash bed is 25-30 feet long, approx. 4 feet wide. Last year I planted two hills of melons at one end but otherwise the bed contained Delicata and a variety of Kubocha squash. I started lasagna beds surrounded by lawn, hence, the problem with Creeping Jenny as well as witch grass that puts out runner roots. The bed is kept weeded until the squash sends out long runner vines. There will be a general mass of leaves. Once I can't get underneath them to weed, the weeds start to extend from the lawn into the bed.

Thanks for pointing out the water problem. I hadn't even thought of that since the weed block plastic is supposed to "let air and water through". I have used repellant spray for deer and never thought to look for one that might work for mice. I think it is mostly mice damage since the voles are too busy underground eating the beets and carrots. Last year we had a drought but we're out of it now, at least for the time being. We have a pretty high water table most years but if this summer is like last, I will have to do some extra watering.

I'm glad I asked. I was mostly thinking about suffocating the soil with the plastic. I have a great earth worm population so it will be interesting to see if that changes if I use the weed block.

I'm in zone 5, also, and love, love, love my polypropylene for growing squash and melons! In my experience..regular weed barrier is just way too thin and weeds grow right up through it, and it's a big mess in a couple of years. I have been using the same polyproplene weed barrier for 6 years now, and it's great! I could NEVER tend a garden as large as I do without it. I plant my squash, put in tall stakes with flags, so I can tell where the root zone is for watering after they fill in...water and good to go!

Also....I have a ton of earthworms...meant to say that...it is woven and breathes...tons of living things in the soil, lets the rain through, and blocks weeds.