Rain is good. Despite the plant getting watered, rain will have a lot of micro-nutrients. Just be careful they don't get too much water. If they appear wilted or yellowing, that is too much water. Rain for a few days is alright though.
I have 30 different types of peppers growing. My Thai's are just producing. It took a while but now they have exploded in peppers.
My jalapenos have been producing since late April, but the peppers have been small.
I am just now getting habaneros (orange) and should get them through September. Habaneros are mid to late bloomers. Hotter peppers usually are. In MA, you may be looking at sometime in August and the production will be limited because of the short season afforded by the climate there.
I live in AZ with 110 degree full sun and I'm still waiting for Scotch Bonnets and Bhut Jolokias which prolly won't produce until August or September.
I'm already getting cayenne peppers out the ying yang. They are an early season pepper. You should start seeing buds very soon.
Tabasco must be a mid-season bloomer. I'm still waiting too.
Fertilizing: If the plants are potted, be sparse on the MG and only use it once or twice a month. You could try fish emuslion too. Pepper plants love it and it is less harsh than MG. I've had tremendous results using fish emulsion.
Indoor/outdoor: If they are outside, they must be outdoor. You will have a short season, but you can take the plants inside over the winter and they may survive to next year. If they do, and as established plants, they will produce much more fruit quicker next year.