Nice and big, ready to be planted for sure.

That is what happens when you do it in hurry, too fast.
Hardening off has to be done slowly, to give the plants time to adjust. It can take up to a week or more to do it right. Even though the drooped ones will recover but you wouldn't want that to happen.

Seysonn

Did you just put them out and leave them out? I'm not an expert at hardening off because I wintersow most things, but I've always thought, as Seysonn has pointed out, that you do it gradually, a couple of hours the first day, more the second day, working up to leaving them out overnight after about a week or so. Yours look a little shocked, maybe from wind or too much cold too soon.

Caryl

They are a little shocked but bounced right back. I put them under a big tree for partial shade and sun. As long as doesn't freeze they stay outside and will put them in the full sun starting tomorrow. BTW they went from 70 degrees to about 55 for that shocked look. They have recovered and have many flowers.

I'm not sure what zone you're in, but as others have mentioned, hardening off should be done more gradual/delicately. Generally the hardening off schedule looks like this:

Day 1 = full shade

Days 2-3 = 2 hours of light then full shade

Days 4 = 4 hours of full light then shade

Days 5 - 6 = 6 hours of full light then full shade

Day 7 = 8 hours of full light then shade.

Plants should be checked each morning during the hardening off period to see how well they have bounced back from the previous days stress. If the plant looks too stressed (wilted) you should be more conservative with your hardening off times.

As noted, hardening off causes the plant stress. The more stress they are under, the more likelihood that stress will lead to developmental stunting. Too much stress and you will permanently cause developmental stunting which will lead to weak growth, weak flowering, weak root formation, low crop yield, etc. (been there, done that, got the t-shirt).

Hardening off should be taken very seriously. If done wrong, it can definitely affect your harvest for the rest of the season.

Right after you harden them off, you will then want to plant them into the ground immediately which will cause... you guessed it, more plant stress (transplantation shock). Transplanting should be done on a day in which the conditions are cloudy or right before sundown. Transplanting in this fashion will reduce plant stress by allowing the plant to transpire overnight before dealing with the harsh sunlight the next day.

Transplant shock will be more pronounced the larger the plant (as the plant has more water it in it). Avoid transplanting plants that are large and flowering. After the transplanted plants have bounced back (should take 2-4 days), pinch off any flowers that are below the first sucker node.

The fact that your plants are that large and are flowering now is not a good sign. If you grew them by seed you should have hardened them off earlier/starter them later (depending upon what zone you are in). Generally plants are hardened off six weeks after germination. This is the biggest reason why people fail at growing backyard vegetables when they buy them a big box stores. They misjudge large flowering plants as healthy plants to transplant.

smithmal

It really depends where you live. We're in the north and I don't do all that. I put them out on a shady day for the first day and then they go into full sun for a few days. I bring them inside at night if it's going to be cool or rainy.

Linda

I wanted them to go into shock to stunt their growth. I used LED grow lights for the first time and they grew about 3 or 4 times faster than my old florecent lights. They are doing well now though.

I agree with the nighttime temp thing here in the PNW

Tomatoes are pretty resilient in my experience. Last year I threw some extra tiny seedlings in the ground way too early when temps dipped down in the 40's without hardening them off, and they survived and produced. I also planted some root bound transplants from Home Depot and they did even better. Of course, that doesn't mean I plan to not harden off.

I agree that one hardens off plants for different reasons in different climates but sorry, I just can't relate to intentionally "shocking and/or stunting" tomato plants no matter where one lives. The damage done to the plant's systems - cell damage/death, discoloration of the stem pith, root death, constriction of the peripheral circulatory system, slowed growth, decreased photosynthesis, reduced blooming, etc. - and the effects on future production and overall plant health and disease resistance are well documented. Much of this damage isn't visible to the naked eye but that doesn't mean it wasn't done and that the price for it won't be paid later in the season.

Dave

I think the soil temperature is also a major factor.
I keep checking it. It is about 52F now. But I have covered the raised beds with black plastic since early Feb. I just cut a (+ sign) shape and plant and keep the plastic til August .
I have only noticed that growth is slow but they do grow once the roots grab the soil. At the end of season some of my indets get over 8 ft tall..
Cool weather is a fact of life here at PNW. Our nights low will reach 50F+ sometime in early June. May's average night lows is ~ 47F. June's average night low is about 53 F. July and August average low is about 56 - 58F. Only one or two days in summer the highs reach and exceed 86F. That is why our Heat Zone number is "ONE", a lonely number :D.
The above statistics are for north of Seattle (Redmond area).
So here it is not worth it to wait for the warm weather to arrive soon, like in Mid West zone 5,6, 7..
Wish me a hot season. hehe

Sey

I understand that, Sey. What I'm talking about is the "cold turkey" approach.
<They look a little droopy since they went from 70 degrees to a cool 45 with a little rain last night. >
From 70+ degrees zapped to 45 degrees and rain. There is no need for or benefit to that. That is not hardening off no matter how you define it and those plants in the first picture were damagedas a resultof doing it.

And based on the comment
<I wanted them to go into shock to stunt their growth.>
It was intentional.

Dave