If you live in zone 6, planning the planting times for your garden seeds will help you to be prepared for a bountiful garden. There are basically two types of seeds, the ones that will germinate in cool temperature and those that need the warmth for germination. We tend to divide these into three growth sections, the early spring, the summer and fall crops. You can make the most from your garden by following a schedule of plantings.
Find the crops that you want to grow but that need a long growing season. These are the plants that you will need to start indoors several weeks before the planting dates of early June. Plants like cabbage, tomatoes, peppers, and Brussels sprouts should be started around March 1 to give them time to get big enough before planting.
Wait until after April 15 to get your early seeds like lettuce, spinach, beets, peas and radishes into the soil. These plants should thrive under the cooler temperatures. If a hard frost is forecasted, throw a sheet of translucent plastic over the rows to save the little seedlings from being killed.
Plan on doing the majority of your planting soon after May 15. The dangers of frost are pretty slim and you can plant your beans, potatoes, sweet potatoes, carrots, melons and cucumbers. It will still be pretty early for the tropical plants like tomatoes, okra and peppers which really need warmer soil. They can be brought outside on warm days for conditioning but will need to be brought back in for the night.
The beginning of June is the time to set out your warm weather plants. The soil will have consistently warm temperatures and with enough water, they will outgrow any that were planted earlier. You can also start another rotation of beans, and fall cabbage. If you have the space, corn can be planted now as well.
Carrots, beets, broccoli and spinach can be planted around the end of August for growing into the cooler days of fall. Turnips and parsnips will actually taste better after a little frost. Mustard greens, endive and lettuce will grow quickly enough to beat the frost that usually hits around October 15th, and maybe a last sowing of beans. Don't forget to get your onion sets and garlic into the ground for the spring.