Square Foot Gardening Forum

Hello Guest!
Welcome to the official Square Foot Gardening Forum.
There's lots to learn here by reading as a guest. However, if you become a member (it's free, ad free and spam-free) you'll have access to our large vermiculite databases, our seed exchange spreadsheets, Mel's Mix calculator, and many more members' pictures in the Gallery. Enjoy.


Search
 
 

Display results as :
 

 


Rechercher Advanced Search

Latest topics
» New England, December 2016
by Scorpio Rising Yesterday at 11:36 pm

» N&C Midwest: December 2016
by Scorpio Rising Yesterday at 11:19 pm

» December 2016 Avatar: Show your Winter Season Colors!
by Scorpio Rising Yesterday at 11:17 pm

» Garlic: Freeze, thaw, and heave
by Scorpio Rising Yesterday at 11:13 pm

» Tomato Tuesday 2016
by AtlantaMarie Yesterday at 8:51 pm

» AtlantaMarie's Garden
by AtlantaMarie Yesterday at 8:46 pm

» Mychorrhizae Fungi
by sanderson Yesterday at 8:30 pm

» SFG not giving the results I expected
by No_Such_Reality Yesterday at 7:21 pm

» New Member
by trolleydriver Yesterday at 4:14 pm

» TrolleyDriver's Compost Thermometer
by trolleydriver Yesterday at 1:32 pm

» Mid-Atl - Dec 2016 - Seed Catalog ?
by CapeCoddess Yesterday at 12:32 pm

» Live and learn
by jimmy cee Yesterday at 10:56 am

» First season SFG results / lessons learned
by countrynaturals Yesterday at 10:36 am

» CANADIAN REGION: What are you doing December 2016
by Kelejan Yesterday at 9:46 am

» Mid-South: December 2016
by sanderson Yesterday at 3:39 am

» 1st Seed Catalog Arrived :)
by sanderson Yesterday at 3:30 am

» Eat Broccoli Leaves? Brussels Sprouts? Cauliflower?
by sanderson Yesterday at 2:55 am

» Winter's Coming!
by sanderson Yesterday at 2:53 am

» Dry versus fresh spices to infuse vinegar
by sanderson Yesterday at 2:50 am

» 2016 SFG in Brooks, Ga
by sanderson Yesterday at 1:28 am

» Holy snow Batman!
by sanderson 12/2/2016, 5:46 pm

» Senseless Banter...
by MrBooker 12/2/2016, 5:17 pm

» Blanching and Freezing Vegetables
by sanderson 12/2/2016, 4:59 pm

» Your Christmas wish list?
by sanderson 12/2/2016, 4:29 pm

» SFG Adventure of a first time gardener in ND
by sanderson 12/2/2016, 4:14 pm

» Second Year SFG in Canada
by trolleydriver 12/2/2016, 2:59 pm

» Fusion Life Brands Power XL pressure cooker
by CapeCoddess 12/2/2016, 2:39 pm

» Asia Region -Showcase of Gardens - Show Us Yours
by sanderson 12/2/2016, 2:14 pm

» December: What to plant in Northern California and Central Valley areas
by countrynaturals 12/2/2016, 1:13 pm

» Gardening in Central Pennsylvania
by countrynaturals 12/2/2016, 12:52 pm

Google

Search SFG Forum

What are GDD's?

View previous topic View next topic Go down

What are GDD's?

Post  boffer on 4/17/2010, 9:52 am

This question came up in another thread.

GDD=Growing Degree Days

It's the amount of time a plant must spend above a certain temperature to reach maturation.It also applies to the life cycle duration of pests.

It's used by commercial farmers to determine when to apply pesticides so they are most efficient. Also, to determine when to prepare for harvest and transportation to market.

The 'amount of time from planting to harvest' that you read on seed packages is just a guestimate based on GDDs. If you have a cool summer, it takes more days to accumulate the hours. If you have a warmer than usual summer, it takes less.

Corn and tomatoes need 1400-1800 GD to reach maturity depending on strain. Dandelions take about 75. It's hard to find values for different crops.

The calculations are basic, based on high and low temps for the day. I found an auto web site here that charts an accumulative graph of GDDs throughout the year, based on the data from an automated weather station that's 10 miles from my house. It also contrasts the current data to an historical average.

One advantage to home gardeners if this information was easier to find, is when to start looking for squash bugs. By tracking GDDs, the experts know at what stage of development a bug is in, and when it is going to start causing damage. They can pinpoint their emergence to within a matter of days.

There's some google savvy members on the forum, maybe they can find more info geared toward homeowners.

boffer

Male Posts : 7392
Join date : 2010-02-26
Age : 63
Location : yelm, wa, usa

View user profile http://boffer.us/

Back to top Go down

Re: What are GDD's?

Post  martha on 4/17/2010, 3:47 pm

as soon as I figure out how to interpret this, the information on the referenced web-site will be really useful!

martha

Female Posts : 2188
Join date : 2010-03-03
Age : 59
Location : Acton, Massachusetts Zone 5b/6a

View user profile

Back to top Go down

View previous topic View next topic Back to top


 
Permissions in this forum:
You cannot reply to topics in this forum