Yes, the WoW will only help protect against cold temps but the plants still need to be acclimated to increased sunlight and the outdoors in general.

Would also wonder if your soil temps will be high enough to support the toms if planted that early. Unless the soil is at 60F, the tomatoes will just sit there and sulk until it warms up sufficiently so no real benefit to planting out early, WoW or not..

Agree with gardengal. Plus you are using containers - much cooler soil temps than in ground and quite prone to rapid changes in temps. You would need to insulate the containers as well as the plants to prevent stunting and/or freeze damage - something like wrapping them in big bubble wrap. With a good freeze you could end up with no damage to the tops but dead or damaged roots.

WOWs are really intended for use on in-ground plants where they can also trap heat from the warmer soil temps.

Dave

Thank you! I am in zone 4 and would love to see the pics!

The above pic is when we lived in Z5 in Central Square NY. I took more photos (on real film :-)) back in the 90's and early 2000s when I lived in Z4, but will have to dig then up If I have time. As you can see above, I used some thin scrap plywood we had for platforms for the WOWs.

Your plants still appear to be quite small using the pots for scale. So they could easily go another 7-10 days at least as is. Plus if you just transplanted then they need some recvovery time before transplanting again.

Or if you want to experiment, try planting just a couple out now as you planned and see how they do. Hold the rest back for replacements if needed. That way you'll know which works best.

Dave

Thanks for your reply! I was hoping to plant them outside in the WoW in about 2 weeks, not right now. Do you think that would work?

They'll work fine in 2 weeks. They'd probably work fine now too. Where are you/what's your average daily high/low these days?

Thanks! I'm in Boise, ID. For the next 10 days predicted low is 33 and high is 67.

I just checked your forecast, and it isn't great. You'd probably be best to keep them inside for a couple of weeks then reevaluate....they'll do much better. Assuming you are using lights, right?

Keep them inside until the temps warm a little. Thw wows will protect them and keep them alive, but they won't grow much in cool temps. Your 10 day forecast won't do the plants any good, so just keep them in until the weather improves a little. Like digdirt2 said, if you want to put one or two out as an experiment...

Soil temperature is a much better indicator of when to plant out tomatoes than is the air temps. Even with warmer days (in the 60's), if you soil has not sufficiently warmed up, the 'maters will not grow.

What temperature should the soil be?

At least 55F........60F+ is better :-)

I'm a bit late to the discussion, C.S., but I've always set up my WOWS and wait a few days to a week before planting. That way the soil immediately below warms up fairly nicely. It may be too late for this year, but may help next. Oh, and I never harden off the plants. Honestly, it's rather on the coolish side when I use them (Michigan). Don't think the plants would appreciate going thru the process.

Personally, I think plant maturity is a lot more important than hardening off here, when it comes to planting early under frost protection. We've never hardened off anything under those or milk jugs, and the implements seem to protect them from the environment just fine, due to the UV protection, wind protection, added humidity, and added warmth. I wouldn't leave them on when it gets to ~80° F., as that can damage them (at least with milk jugs), unless you give them more ventilation than the cap hole provides. However, if the tomato plants are too young, you're probably not going to notice much benefit to putting them out early. I have had plants that were too immature struggle to grow under milk jugs, though, but more mature ones seem to love it.

That being said, I'm not saying you shouldn't harden your plants off in this situation (maybe it helps), but I don't find it a necessary step, personally.

Note: As I mentioned using milk jugs, it's important to have ventilation all the time. Throwing away the cap is sufficient for cooler temperatures.

You're basically creating a mini, unheated greenhouse. I believe the water in the Wall O Waters may improve matters, though. We've had great results with those (with store-bought plants). I've used milk jugs only on those I've started myself. The plants don't get mature enough starting them in my unheated greenhouse to make it very worth using milk jugs, though. I might start some tomatoes indoors next year.

This year the tomatoes are going to be planted later-than-expected anyway, since our shade trees are coming down later than I would have wanted to transplant.