The seeds are in and I have a rough planting layout for the 2012 season. Next is developing a schedule for starting seeds and setting out plants. I found Rachel’s post on her Grafix Muse Garden Spot blog a good starting point for information and I highly recommend a visit. All the calculations needed to develop the schedule are based on average last frost date for your area. A source of that information is Plant Maps, which lets you put in your zip code and find last frost and first frost dates. Bolton is hardiness zone 5b with an average last frost date of May 1-10 (I used May 7 for the date) and an average first frost date of October 1-10 (I used October 8). Note: the new USDA hardiness map shows Bolton to now be in hardiness zone 6a, so who knows if the last frost dates I used are correct. A few weeks probably doesn't matter and I use my own gardener instincts to adjust actual planting dates.
Next you need to determine the safe date to transplant based on the hardiness or tenderness of the variety. For example, tomatoes are safe to transplant 1-2 weeks after the last frost date, while broccoli can be set out 2 weeks before last frost. From the transplant date you calculate backward to the seed starting date. To do this you need to know the average growth time from germination and the time to germinate. The result is the seed planting date for each variety.
Given the last frost date, most of the information you need to determine a planting schedule is available on the seed packet or in the seed catalogs. With these numbers, you can calculate back to the seed starting date, or you can take the lazy way like I did and use one of several online resources. Johnny’s Seeds has a seed starting calculator here. And Maggie Wang posted an easy to use spreadsheet on the You Grow Girl blog here.
With all this help I now have a planting schedule I put on Google Documents. You can see my schedule here, which will be updated with actual dates as the season progresses. It is only a few weeks until the first seeds go into trays and I am really looking forward to the new gardening season. By starting my own seeds, I am no longer dependent on what I can find at the local greenhouses and garden centers.
