Candy Showers Snapdragon Wilting in Greenhouse

Hi, I have been growing some seedlings of Candy Showers Snapdragon in my garage, and just moved them to the greenhouse, and they wilted. I brought them back to the garage and now they are perking right up. It did not seem too hot in there or too cold, and i had it vented. They were planted on Jan 3, and transplanted on 21st of Feb into baskets. They are very healthy. I am in Oregon and temps have been highs in 50s, and lows in 40s outside. Temp in garage has been about 55-60's. Temp in greenhouse on the gauge said 61. Not sure why they don't like the greenhouse. Anyone have any ideas?

Prior to placing seedlings out in the sun, they need to be hardened off, always. This means nothing more than accustoming them to bright light conditions, which they would not experience indoors or in a garage. If plants are not hardened off, they show damage by wilting or, in worse cases, by severe sunburn where the leaves turn white and die. (Note: It's nothing to do with temperature or wind.)
You can do this very easily in a couple of ways:
Set them outside in the shade for a few days (5-7).
Or make some shade in the greenhouse for them, e.g. with a shade cloth covering, and use it for that approximate length of time.

Edit: I guess I might as well add... There's no need to haul plants back and forth from sun to shade, as many people seem to think is necessary. Hardening off can be done very easily and is foolproof in the way I described - simply by setting in the shade.

Shade cloth works very well, whereas trying to build some other structure to provide shade can be more difficult, as you have to account for the sun's movement during the day.

This message was edited Mar 9, 2016 11:20 AM

This message was edited Mar 9, 2016 2:02 PM

Ok, great, thank you so much. I have been taking them in and out and they still are having some trouble. I will try the shade cloth.

If you don't have shade cloth handy, why not just set them outdoors in the shade? That would be the simplest thing. I assume it's not freezing overnight in your climate?

Well, I always worry about rain here in Oregon. I do have a tree i can put to use, and may do that. I did go buy a shade cloth for the greenhouse last night, but could only get one that blocked 75% of the sun. Otherwise I would have had to buy online. Unfortunately i could not wait for the shipping so I opted for the one locally. i hope it is enough. Otherwise I will use the tree.

75% blockage is fine; 50% would be better. The point is to filter the light somewhat, in order to reduce its intensity, so that your plants can become accustomed to it without suffering the effects of sunburn.

Blocking the light completely would be the opposite of what you want .

Use it for a few days and once it's removed, your plants should be fully hardened off.

Great news, thanks for your help.