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Name: Gregory D.
Status: other
Age: 60s
Location: N/A
Country: N/A
Date: Wednesday, November 20, 2002

I have checked your site and found that grass germination is best when the soil temp. is 50 to 60 degrees. My question is this. If I were to take a soil temperature, at what level should I measure? Surface, 1/2 inch below surface, 1 inch below, etc? In the shade? Sun? Each level/location will give me a different reading.

shade, and 1/8 to 1/4 inch depth possibly helpful:

Anthony R. Brach, Ph.D.

Good question. I suspect that there is not a "standard depth". The optimum germination temperature was probably determined in a lab or greenhouse where the temperature is the same at any depth. You are correct, each level/location is going to give a different reading. Another related factor is moisture content, which also depends upon temperature. That is why commercial re-seeding is often covered with a layer of straw to reflect some of the sunlight and retain some of the ground moisture. The species of grass also is an important variable. Winter rye, bluegrass, centipede, and so on all have different "optimum" germination conditions. In addition, where you live has an important effect on all of the above. I'd suggest you ask your local agriculture extension office or garden store for a recommendation relevant to your climate.

Vince Calder

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