I have used WOW's for years and my plants have grown out the top many times and have not only survived by thrived. Your 8" plants probably don't have roots growing further out than the WOW so I would go ahead and use them. I get a good 2 weeks extra with them.

Don't forget to put 3 stakes/ WOW when you plant, they have a tendency to fall over and squash your plants.

i love the wow, sf stays cold and foggy mostly in the "summer"i always get a head start on tomatoes and this year i am trying string beans, i fold the wow down when the plants get 12 inches and leave the wow up half way all season because it keep the plant warm, we stay in mid 60's and high 50's , since i started using wow i can now grow tomatoes

What is a WOW/Season Starter? I didn't have any luck doing a search, so can you explain it? It sounds like something I might want to try...

a wow is a Wall of Water. Here's one site but they can be found lots of places:

Here is a link that might be useful: wall of water

I just gave away my WOWs. After experimenting for a few years to get an early start with tomatoes, peppers and other heat-loving plants, I had to conclude that in my garden, it wasn't worth the hassle to use them.

My guess is that it works best for gardens with very well-drained soils that heat up fast in spring. If the soils are dense and cold, the roots will be cold too and the thermal mass in the WOW protecting the stems and leaves aren't going to do much good. I suspect that's why the instructions now say that the the WOWs will only work with small, 4" plants!

I'll stick with hoop houses for any season extending with heat-loving crops. They do a better job of heating up the soils and holding in the radiating heat on cold nights.

Last year, after amending the soil with compost, II sunk my Wows about 6 inches into the ground.

I laid an empty Wow loosely in the trench. I planted my tomato in the middle and buried it up to the first set of leaves. I placed a bucket over the plant, then filled the WoW 3/4 full to use in the teepee mode.

When the weather had warmed up and the plant had grown, I filled the tubes, then turned the top 5 inches or the WOW over to the outside all the way around which made a collar that made a sturdier pot and sealed the tubes so dirt could not get in them.

I had to squeeze some water out of the tubes to do this but it was worth it as I had no moldy awful Wows to contend with this way.

Then, I filled the WoW with soil up as high as the first leaves on the plant so the Wow was functioning like a regular pot. I continued to fill the pot as the plant grew until the pot was almost full.

At this point, I placed wire cages snugly around the WoW to support it and the plant as it grew on out. I watered into the pot and misted the tomato plant lightly with Messenger every 3 weeks.

I had Celebrity tomatoes that ripened with the Early Girls.

This year I am going to try this system with squash, melons, and cukes.

Good luck with this year's garden.