Mike,
If you are ok with the device, I can ship it to you. You can keep it for a few weeks. Maybe along the lines we can come up with ideas to test for something else and how. In any case, I think the data should be reliable, verifiable and the tests repeatable. You can achieve this with an electronic setup only.

Wine or whiskey barrels work well.  The wood is a natural insulator and allow moisture to escape naturally.  It has worked for me very well.

Whiskey barrels , half cut, are between 30-40 bucks in LA :/

Phil,

As Pete mentioned above, Igor’s (greenfig) excellent report on pot temperature really got my attention last year.   I had wanted to acclimate and grow my baby figs out in full sun without cooking them in the pot.  My quick fix, late last summer, was a 50% shade cloth and that saved the plants for the time being. 

The plants were wintered unprotected and this spring, I let them break dormancy exposed full sun and the elements.   No more coddling those babies!   So far no problem, leaves might be a bit smaller but, they seem to be thriving.   Straw for protection has been mentioned and I too found it an easy fix.  Cheap bailed straw from a local feed store protects pots from full exposure to sun, also put leaf mulch between pots. Everything is wet down when watering, which gives roots venturing out of pots a place to grab more moisture as need. 

Figs below may look a little haggard because, we are day two into a major Santa Ana condition…….. super dry, hot and windy.    I’ve noticed they protect themselves in the condition by closing or curling their leaves in a wee bit.   

 

green fig,
Thank you but I am going to attempt to record by hand. I want to see just how accurate I can get this way and what technique I may need to develop so I can do this across a large number as well as smaller test sample plots or random testing, etc. 
I certainly appreciate the offer and may take you up on it later if it still stands.
thx,
mgg
I'm going to call a good buddy tonight who's a soil scientist and see what her take on this whole issue is.

Mike,
No problem, the offer stands.
Using the device by a different person always may bring some improvemens.

Please let us know what she says.

I thought figs like warm roots. Bill's figs, all his pots have covering on them. Don't the covers retain the heat?

Bill's figs:


My plants also has a auto drip irrigation, so the soil never dries out.

if there is no water restriction, just water to cool the pot. response from the trees are immediate. today the temp went up to 95. leaves were drooping by 3. gave water, in less than an hour, they all perked up. 

providing water is not an option, some sort of shade might help... but stress to the tree will still be there. up till last yr, i kept my trees on back deck where they get some shades for the containers. but the leaves will still droop when the temp goes above 90-95.

the containers are always wet. i don't let them go dry when out in the sun. letting them go dry means losing all the leaves, and setting the trees back.

Jack, that is a great little fig orchard you have there.

Peter, Bill definitely knows what he is doing.  I think he is in your zone?  I am not concerned at the moment, but last year I think we had 20+ days in mid 90's.  I don't want to cook my little trees, but I want them to soak in as much sun as possible!

Pete, thanks - I may be overly cautious, but sometimes I may get stuck out of town and forget to ask someone to water them.

Hi Bosco,
With all that straw I would fear that honey pot to be too appealing for rodents ... Unless you've got a cat army .

I would use wood, like building a closed fence over the dirt and around the pots . If they are all in the same area you could make a wood protection around all the pots at once as opposed as doing one per pot, and it still could look nothing like messy .
When watering the pots, you would water the wood, and wood would retain water and moisture for later in the day .

An alternative is to put the fig pots under or around another tree, like a cherry tree .

Just my .02.  During the hottest part of the summer I setup a timer to water my trees on drips three times a day.  I've never had a problem from heat (from what I can tell), just with pots drying out quickly.  I put raised beds (6" high) to contain my pots so perhaps that provides some shade to them.  I also grow them close enough together that the fig leaves may shade the pots as well.  We only get 90+ degree heat for a week or two here per year, though.  I'm experimenting with cloth pots (root pouches) for my larger figs that are supposed to breath better than solid plastic pots.  Will probably post something to here or to my blog if they work out particularly well.

Wheat straw will reflect heat.
Its cheap, it spreads out and it holds moisture.
Rodents might be a problem in the city, but mice will make beds of anything not just straw.
The hawks and feral cats have kept the rodents at bay for me.
I've never heard of people having so many rodent problems when straw is mentioned.

I'd put straw on my pots if I grew in pots.
(rodents would never want to stay with the watering schedule!)
My 2cents

Doug

Mulch is such a good idea and the figs seem to really like it..be it wood chips or as Doug mentioned straw, it all helps.