Determining Planting Dates

Sometimes determining planting dates can be tricky.  We know that our fall vegetable garden should be in and growing when it is still hot, and dry, outside.  We also know that many cool season plants don’t grow well in the heat.  What to do?

Weather Station Map
Weather Station Map

The first step is to find out when the average first frost date is for your area.  Luckily in Georgia we have the Georgia Automated Environmental Monitoring Network (AEMN) which has weather stations all over the state.  These weather stations collect weather data year after year, including first frost dates.  This information can help us determine when to plant. Let’s say you live in Dallas, Georgia and you want to plant broccoli, specifically the cultivar Green Goliath.

If you visit the AEMN website, www.georgiaweather.net, and type in your zip code, 30132, you will be directed to the Dallas Georgia weather station.  Following the link for first frost date you will find years of data for your use.  Let’s just use the last six years of collected data:

2012    Nov 9

2011    Oct 30

2010    Nov 6

2009    Oct 19

2008    Nov 10

2007    Nov 7

Using this information we can determine when we want to make sure the broccoli has matured and hopefully been eaten and enjoyed.   These dates have a span of 22 days.  The earliest is October 19th and the latest is November 10th.  The October 19th date looks like it may be an outlier.  (A statistician could do better justice to this analysis I am sure!)  So, you may decide that Halloween, October 31st looks like a good date to work with.

According to The Southern Seed Exchange catalog, the information for Green Goliath says 55 days to maturity (DTM).  In this case the DTM is from the transplant stage.  So, if you are starting your seeds to create your own transplants you will need to add about 20 days to that number, 75 days.

Look at October 31st and count back in the calendar 75 days.  This leads us to August 17th as the date to plant your seeds. Experienced, and maybe obsessive, gardeners mark in their calendars key dates such as “100 days until average first frost date” and “75 days until average first frost date.”

If you live in Dallas Georgia today, September 17th, is 44 days until your estimated average first frost date.  If you are feeling lucky with the weather, you might find some Green Goliath transplants at your local plant store.

Happy Gardening!

Becky Griffin
Latest posts by Becky Griffin (see all)

1 thought on “Determining Planting Dates”

  1. Excellent method of determining when to plant, even without a statistician. The AEMN site would seem to be a significant tool for the gardener.

Leave a Reply