summer growing days revisited
We looked at the weather station data again and decided to go with the heavy frost (-3c) instead of the light frost (-1C) definition for a few reasons.
1) In the fall, a light frost really does not affect anything as all of the above ground veg have already been harvested. Only root veg like carrots, beets, turnips, etc are still in the ground. We generally harvest those shortly after the 1st heavy frost.
2) In the spring, you have to predict when the last frost will be, but that in conjunction with time off work to plant means we usually don’t even plant in the ground (or transplant out of the greenhouse) until the end of May.
The original definition of light frost growing days:
Actual Growing days between light frost (-1C) dates
Year #weeks #days
2003 25 176
2004 22 156
2005 22 156
2006 no data no data
2007 21 147
2008 22 154
2009 18 129
2010 17 119
2011 21 149
2012 23 162
The new definition of growing days using heavy frost:
Actual Growing days between heavy frost(-3C) dates
Year #weeks #days
2003 28 198
2004 29 201
2005 32 222
2006 no data no data
2007 22 153
2008 23 160
2009 26 179
2010 20 143
2011 24 167
2012 24 165
some simple statistics:
| stat | light frost days | weeks | heavy frost days | weeks |
| min | 119 | 17 | 143 | 20 |
| average | 150 | 21 | 176 | 25 |
| max | 176 | 25 | 222 | 32 |
| stddev | 17 | 2 | 26 | 4 |