Poor carrot germination

I'm having terrible luck germinating carrot seeds. The varieties are "Baby Babette", "Round Romeo", and "Sunshine Orange and Yellow", all from Renee's.
I'm sure that the seeds are fresh. Everything else we purchased from Renee's has been excellent, this is not an indictment of the vendor.
Per the package instructions the seeds were sown 1/4" beneath the soil and kept moist throughout the 10-20 day germination window. The soil is San Joaquin Delta peat contained in raised beads. This soil has not had carrots sown in it before now. "Baby Babette" and "Round Romeo" failed to germinate at all in both of two successive sowing, and "Sunshine Orange and Yellow" germinated at less than a 50% rate.
USDA zone 6, Sunset zone 7 and/or 9.
Any ideas what we may be doing wrong?
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Steve said:

How warm has it been for you during these sowing attempts?
"Carrots (Daucus carota) are cool-season plants that grow best at average temperatures between 60 and 65 F. The optimum soil temperature for seed germination is 55 to 75 F. Seeds will not germinate above 95 F."
http://hgic.clemson.edu/factsheets/hgic1305.htm
See also: http://www.aginfo.psu.edu/news/april00/soiltemp.html
One fairly traditional tactic to get carrots to germinate in summer temperatures is to put a board over the row to keep the soil cool and moist. Check the board a couple of times a day and remove the board once you notice seedlings beginning to emerge.
--
Pat in Plymouth MI ('someplace.net' is comcast)

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On Fri, 29 Jun 2007 05:23:58 -0500, snipped-for-privacy@someplace.net.net (Pat Kiewicz) wrote:

Thank you, Pat. After reading the links I think temperature may have been the issue. I'm going to try the board method.
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On Fri, 29 Jun 2007 05:23:58 -0500, snipped-for-privacy@someplace.net.net (Pat Kiewicz) wrote:

Thanks for the tip Pat. So simple.
Simple is often the best, eh?
Charlie
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