It is the most amazing feeling, isn't it?
Where I live in Kansas we get the odd late-spring hard freeze, which are too cold for my
greenhouse alone to protect against, so I covered my bok choi and other greens with 3 layers of plastic. They survived and gave me over a month's good eating at which time the salad greens outside the greenhouse started producing. THEN I had salad coming out of my ears, not that I am complaining!
I am trying to decide what to plant in there this Fall. Frost tolerant plants do the best, but I am seriously tempted to plant cucumbers.
As for a watering trough, I found a washtub full of
water to be a great convenience while the seedlings were small. They need very little water but they need it immediately. Older plants need a lot of water and it was simpler to run a house out and give them a good drink every few days, but seedlings need fiddling over and I did not want to walk into the house to get just 2 cups of water. The washtub of water would last me for 2 weeks while the plants were small.