I also have a very short growing season although it is somewhat made up for by having very long days. I have to admit I have never gotten tomatoes to produce either. But I try every year. This year we are having a very hot sunny beginning to summer. I bought starts and let them grow in my 'garage greenhouse' until they were about12" tall and then put them in my raised bed with a poly cover on it. That was around the third week in May. Kept the cover on which allows filtered light to make hardening them off easier, then left it off during the day but back at night. Now I leave it off all the time. If the weather stays like it is I may just get harvestable tomatoes. They are a brand called Siberian which are listed as 'outdoor' tomatoes up here. If the weather turns cool I will put the cover back. I also have two peppers in their, another tough one for me. I also set up a drip system this year to get more consistent and deeper watering so we will see.