I can thoroughly recommend the Tinytag data loggers made by Gemini. I use
the Tinytag plus2 logger which can take two temperature probes and store
data. It is weatherproof, although I would not leave the logger unit without
some cover from the rain. It is stand alone operation, but it needs a PC or
Laptop to offload the data. Software is provided that can produce graphs or
tabular values. If set to sample at one minute intervals it has capacity to
store 11 days worth of data. The calibration is excellent, and better than
0.05C at 0C, from my own calibration checks.
http://www.geminidataloggers.com/

--
Bernard Burton
Wokingham, Berkshire, UK.

Satellite images at:
www.woksat.info/wwp.html
or
www.btinternet.com/~wokingham.weather/wwp.html
"Keith (Southend)" wrote in message
...
I was wondering is there anything available on the market that can
record the grass minimum temperature(s) and store (log) the data for a
number of days? Someone I know asked me so he could monitor the grass
temperature in his allotment, but it would also be something useful for
myself as I lose any data when I go away from home for two days or more.

Thanks
--
Keith (Southend)
http://www.southendweather.net
e-mail: kreh at southendweather dot net