I used to live in buffalo ny and that was similar to Rochester. Start seeds of sunflowers indoors now with a light set up. I use shop lights with fluorescent bulbs pretty inexpensive. Also morning glory vines. Tall marigolds and zinnias would be good and fast growing. we used to start our veggie and flower seeds mid March and have them in round a little before Memorial Day of right around that weekend. I would always make a "sunflower house" for our kids to sit in and they usually had it by july ish
