Yikes....sounds like ya cooked 'em before they grew up!

Tomatoes can stand full sun in 110 F degree heat so long as their roots are damp and the is ground kept cooler with mulch but...greenhouses without ACTIVE ventilation can get upwards of 140 F degree very quickly.

You might want to start (re-start?) by ignoring the instructions that came with your greenhouse and study up on basic tips and techniques to greenhouse growing in particular.

Try whatever search function you like to use on the Web and look for Greenhouses Ventilation or Greenhouse Fans or some such. Some sites that offer products (like fans themselves) offer techniques and and information to help you understand all the dynamics.

Yep, unfortunately its not as simple as putting the greenhouse together and putting the plants inside...even IF you leave the door open.

Brace yourself....others will offer you help here as well.

Did you harden off your plants slowly,by that I mean just put them in the sun for a few minutes at a time,and increasing the time 10 minutes a day for about 2 week period.
Until your plants get some growth to them,to not let them dry out at anytime,keep them moist and well ventilated,keep a outside thermometer inside the greenhouse,so you can monitor the temperature at all time.
It will be a lot easier starting your seeds in the greenhouse in the shade to begin with,good luck.

Hi,

It sounds like you took them out a bit early. They are very tender and need to get used to the new environment. Starting in shade is good. You could also have them in a sunny spot briefly at first, then for longer periods till they are used to it.

Like taking your child to the beach, young ones will sunburn very easily and the wind can dry them out.

It's alright for plants to wilt a bit, they often recover to a surprising degree. Just move them back indoors or to a calm, shady spot for a few hours or overnight. They'll also need a little more moisture than for indoors growing to resist wilting, not dripping wet, but evenly moist. Just make sure you're not setting out a nearly dry plant into full sun on a windy day and keep close watch on them the first few days till you see how they react.

Small enclosures heat more quickly so you'll need more ventilation than the directions suggest. Roll up the sides, perhaps.

The first season or two will be full of learning experiences, but you'll get the hang of it!

-Ed

I agree, they were baked.

Its too bad you didn't just try and revive them with water and moving them to shade. I found about 2/3 of them usually recover if you hit them with water soon enough.

Sterling

I did do try that, a few brave little souls survived! I managed to save 4 cucumber sprouts (now 4" tall), 4 Tomato sprouts (now about 3" tall) and a yellow squash (now 5-6" tall) the rest did not make it, I moved them inside and watered them and tried to keep the soil nice and moist, but many shrivled up and died. So my thoughts are the ones that did survive are strong little plants!

I have re-started and have began to dig my beds, the soil looks promising, lots of earthworms (although I have encountered a few june bugs too, I have been pulling them out as I find them. Nasty looking little things!), the soil isn't as bad as I thought. Doesn't appear to be too high in clay content and a fairly dark colour, I am adding some peat moss, super soil and composted manure as I prepare the beds, and am mixing them in well with some of the existing soil.

I've decided to plant around the perimeter of my 14x24' area, to see how things go (or grow!) this year, if it works well I have loads of room in the middle for some nice rows for other veggies or flowers and plants. But 2 beds are 2 feet wide and 24 feet long, and one is 2 feet wide and 14 feet long, so hopefully that will be ample space, and it gets full sun all day.

How tall should the seedlings be before I plant them in the garden? Are there any that I should not try this year?

:) thanks for the imput,
Colly

I assume we are still talking about tomatoes at this point right? How tall? Well, at least a few inches, for my taste, about six inches with several sets of good, healthy leaves. There is the old trick of planting the seedling deeper in the hole you make for it in the garden than it was growing in it's pot. Tomatoes will generate roots from the buried stem.

BUT...your outside weather conditions can be more important the the size of the seedling. If it has not really warmed up in your garden (soil temp too, not just air temp) the tomatoes will mostly just sit around and wait. They might grow a bit, but will not set fruit from the flowers until the evenings are warmer. (You can find this stuff on the net with a Search, I'm sure)

Tip: You are going to have to decide if you are going to stake your plants or let them sprawl. If you plan on staking them (or use wire baskets) you can rig a piece of cardboard to shade them a bit for the first few days they are in the ground.

If you are going to let them sprawl you best get deep dry mulch (like straw) around them early on.

Much more to write about growing tomatoes but.....try the net search for more (other) (Different) tips.