What to start indoors now? (This is for zone 6)
Well, you need to know your last frost date (check with your Ag extension service), and know that it’s an average so add a week or two, then count backward to how long you should start a vegetable before setting it out. (This information is in Johnny’s, and should be in every seed catalog.) So here’s the list:
Celery. It should grow for 8-10 weeks before transplanting out, then only after the soil has warmed somewhat. Nights below 55 F. can cause it to bolt.
Tomatoes: Tomatoes don’t like to spend more than 2 months in a pot, without potting them up into larger pots (a pain), but no matter how soon you get them out, and how you protect them, they’re going to fruit when they’re ready to fruit in warm weather. I learned that from an Italian old-timer years ago, and it’s true.
Peppers: Again, sow 8 weeks before setting out. Keep the soil as warm as possible to encourage germination (80-90F –which means, I don’t know, on top of the furnace or fridge). Then let them be cool at night (in the 50s) for a few weeks, then back to warm (70F day and night.) Good luck on all this, but it does hurry a crop along.
Eggplant: Again, 8 weeks before setting out. (Sounds like a theme..). Again, keep the potting soil as warm as possible to aid germination.
Onions and leeks: Start them now, although I prefer to buy them as plants. More expensive, but you get a much earlier crop. The ones grown from seed can be harvested for a fall crop, or even allowed to winter over.
Okra: My brother in Maine once declared that he’d successfully grown okra, traditionally a Southern crop. I said, “But why did you do that?” BUT, you can start okra 4-5 weks before last frost, and transplant when the soil has warmed. With any luck you’ll have crop failure and not have to eat the stuff (except perhaps in some classic Southern recipes).