Rick, from my brief experience as a grower in a hoop-type greenhouse, tomato plants do great and form very nice root systems at about 40ยบ. If you care to do a few plants that you can put out during warmer days and bring in at night, that should give you a pretty good jump. To my experience (and I've had some concur and some agree) vegetables are fine started indoors, but need a lot more light than we can give them; only the sun will do.
If you're not ready for the greenhouse, cold frames (can be a few straw bales with a plastic sheet or old window frame really does good stuff, too - you just have to be sure to vent it on sunny days or you'll have fried green tomato plants...
Alright, now tell us what irises you would like to try, lol!
