Growing Degree Days alteration?

[Beer2Wine]

It seems that the traditional grape-growing season is based off of the 6-months between April 1st and October 31st...

Living in SoCal....a hot and fairly dry area, my Growing Degree Days (GDD) for that time of year puts me around an average of 4200 GGD (Region 5) which is pretty high and pretty crappy for many of the best wine grapes. HOWEVER.... If I set the calculation a few months earlier on each end, this is what I get:

Mar 1st - Sep 30th: 3873 GDD (Region 4)

Feb 1st - Aug 31st: 3382 GDD (Region 3)

Jan 1st - Jul 31st: 2837 GDD (Regon 2)

Given this info, (and the fact that I dont see much rain after February) could I technically alter or shorten my growing season and grape selection??? Ive read that people will often harvest around the end of August in hotter growing regions like Temecula, and parts of Texas.

 

[robie]

Sorry you haven't gotten any responses. That's pretty technical stuff!!!
Isn't a Malbec a hot, dry climate grape? I wonder how it would do in your area.

 

[jet]

I don't grow grapes, but I thought your degree days was supposed to be for the length of your growing season, not a fixed number of days.

 

[bruno31]

I think this kind of calculation is made precisely to give an indication of how "early" is the region with respect to grape growing. So you should stick with the standard calculation and not try to alter the result.

If there is enough water, the grape will grow under nearly any hot climate. In your region, it will probably be ripe very early and very quickly (shortened cycle starting earlier in the year). There are even grapes grown on some tropical islands, with 2 harvests per year, due to the ultra-short cycle.

This is usually not ideal for quality and complexity, but it never hurts to try!