I created this Excel Workbook to help you plan when to start your seeds indoors, and when to put your transplants out in the garden. To use the spreadsheet, first you need to know your last expected frost date. You can look it up by zip code here. Print out the spreadsheet and enter your frost date at the top. Next, you will fill out the dates for when to set out your transplants in the garden. For example, in the row marked "basil" it says that transplants are safe to set out "2 W after", or two weeks after your last frost date. Count ahead two weeks on your calendar from the frost date that you wrote on the top. Fill in that date in the "set out date" column. Repeat this step for each plant that you want to grow. If you are buying your plants, you can stop here. If not, continue to the next step. Next locate the column that says "weeks from sowing". For basil, it says "3-4 W". Your basil plants will be set out three to four weeks after you sow the seeds. So on your calendar, start at the "set out date". Count backwards three to four weeks. This is the date (or date range) that you need to start your seeds. Repeat this step for the other plants that you want to start from seed.
There is a second tab on the workbook, which is a simple chart for when to plant seeds, trees, and bare root plants when they will be planted directly outdoors. Some vegetables, such as zucchini, will appear on both tabs because you may choose which method you want to use (starting indoors or direct sowing in the garden).