An easy timetable to figure out how many weeks
before your region's last frost date to start your seeds indoors.
12 weeks: Onion seeds
6 weeks: Tomatillo
6-9 weeks: Eggplant
6-8 weeks: Spinach, Peppers, Chives
5-7 weeks: Tomato, Cauliflower, Cabbage, Broccoli
4-6 weeks: Okra, Kohlabi, Kale, Endive, Collards, Brussells Sprouts, Artichoke
4 weeks: Cucumber
3-4 weeks: Watermelon, Squash, Muskmelon, Lettuce
Maybe a little late for most people here this year.
I taped this chart to the inside of my seed box for next year as I seem to have the urge to start my seeds too early.