Growing Degree Days: What are they?
The average Growing Degree Day (GDD) for this time of year is 281. The growing degree units this year is 368.5, which is significantly above the average. GDD’s are calculated each day as maximum temperature plus the minimum temperature divided by 2, minus the base temperature of 50 (I use 50 because that is the temp that sweet corn will start to germinate). For other vegetables, such as squash, pumpkins and beans, I will use a base temp of 60. GDD’s are accumulated by adding each days GDD’s total as the season progresses. If the average temperature is below the base temperature, the growing degree day value for that day equals zero. By using this calculator one can determine the proximity of harvest dates for different vegetables and keep you from over planting in the spring. Why? Because we can only harvest and market certain volumes every day. Produce is highly perishable and the window for mature produce only gives you a short window to pick, pack and sell.
Over the last five years here is what the GDD units have measured from April 1st through May 29th:
2015 368.5
2014 273
2013 267
2012 446
2011 236
2010 427
I hope everyone learned something today! Don’t forget to keep the weeds out of your gardens. Weeds are the number one source for a poor yield. They rob the nutrients from your produce, steal the moisture and worst of all bring in unwanted pests. Happy Tails!
As a new CSA member your comment: “Weeds are the number one source for a poor yield. They rob the nutrients from your produce, steal the moisture and worst of all bring in unwanted pests.” scares me. Rob and Steal ? Aren’t these words a bit strong? Are you going to blast our produce with chemicals to prevent weeds? Maybe I should rethink my investment?
No these words are not too harsh, because it is the truth. Weeds are the number one culprit in the field and in the garden. Unfortunately chemicals do not take care of the weeds in many vegetables, hence it is a major cost in growing vegetables and the reason why the good Lord invented the hoe. My mom, when she was running a crew when I was a kid, (I started in the fields when I was 3) would only want to see “asses and elbows”, and if she didn’t see them she knew they weren’t working. Mechanical weeding is essential to having a productive vegetable field because if you don’t control the weeds you won’t have a crop. End of story. Dad’s favorite saying was “No top, No Crop”. Take care of your crop at all stages, but the most critical stage is when it is small because in most crops that is when the yield is established. – Gary Pahl