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gixxerific
- Super Green Thumb
- Posts: 5889
- Joined: Fri Jun 26, 2009 5:42 pm
- Location: Wentzville, MO (Just West oF St. Louis) Zone 5B
Question on frost dates
Some places have 10, 50 and 90% frost dates, which do you use for figuring out your start dates?
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rainbowgardener
- Super Green Thumb
- Posts: 25279
- Joined: Sun Feb 15, 2009 6:04 pm
- Location: TN/GA 7b
50%
Those dates/averages are derived from historical data going back at least 100 years. Given changing climate, you are much safer using the 50% date than 50%. That is the 50% date is supposed to mean that 50% of the years there will be no frost after that date. But that is no longer true and now it is probably more like 75% of the years there will be no frost after the 50% date. Still not a guarantee, but the odds are in your favor.
Farmer's Almanac tells me for my area, April and May are predicted to be warmer and drier than usual.
Incidentally Per:
https://www.climatecentral.org/news/play ... rend-17097
GLOBALLY Jan 2014 was the 347th consecutive month of above average temperatures. Yes I know, your piece of the world and mine have been below average this whole winter; this is talking about the planet as a whole. Alaska has been having fierce heat wave as have Australia, parts of Europe, etc. Taken as a whole the planet has been continuously above average for nearly 30 years now.
Those dates/averages are derived from historical data going back at least 100 years. Given changing climate, you are much safer using the 50% date than 50%. That is the 50% date is supposed to mean that 50% of the years there will be no frost after that date. But that is no longer true and now it is probably more like 75% of the years there will be no frost after the 50% date. Still not a guarantee, but the odds are in your favor.
Farmer's Almanac tells me for my area, April and May are predicted to be warmer and drier than usual.
Incidentally Per:
https://www.climatecentral.org/news/play ... rend-17097
GLOBALLY Jan 2014 was the 347th consecutive month of above average temperatures. Yes I know, your piece of the world and mine have been below average this whole winter; this is talking about the planet as a whole. Alaska has been having fierce heat wave as have Australia, parts of Europe, etc. Taken as a whole the planet has been continuously above average for nearly 30 years now.