North American Fruit Explorers mailing list at ibiblio

[Sam Franc <franc@oregonfast.net>]

Doreen Howard wrote:

> Claude,
> Exactly how long is your growing season?  I am also in Zone 4, and Esopus
> Spitzenburg is grown locally.  We have about 100 to 110 frost-free days,
> depending on the year.  I agree about its flavor.  It is my absolutely
> all-time favorite apple, and that says much, considering I love so many
> apple varieties.
> Doreen Howard
>  
It is not only the length of season but the degree days of the season.
I guess people who have not grown citrus are not too much aware of the 
value of degree days.
Like you can grow lemons with fewer degree days than a valencia.
And you need even more degree days to successfully grow grapefruit
The same factors apply to apples and other fruits.
Sam

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