Answer: Squash grow very quickly, so you would start them later than peppers and tomatoes. Squash might take about two or three weeks and tomatoes and peppers about 6 to 8 weeks. The tomatoes and peppers can be started a bit earlier than that if you have truly good conditions in which to grow them -- and plenty of space as they will need larger pots the longer you keep them. Most seed packets do give an indication of timing if it is a plant frequently started indoors. As a rule of thumb, if your seeds usually germinate quickly, start them a week later than suggested on the packet.
You might find some of the following general (and detailed) seed starting information useful:
Seedstarting Made Easy at http://www.gardeners.com/gardeners/bgbseedstart.html
Seedling Savvy at http://184.108.40.206/nga/articledetails.taf?id=514&kwd=seed&A...
Corn is not usually transplanted per se but it can be pregerminated by placing it in a folded, damp paper towel and then wrapping it in plastic so it stays moist. Keep it out of direct sun and check often for germination, then plant immediately.
The Tioga County extension telephone number is 687-4020 (56 Main St., Owego). They should be able to give you the frost dates for your area, however remember that these are only an average and the dates in your garden will reflect your particular microclimate so the dates are only a guide.
Good luck with your seeds!
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