Keeping temp in pots down

Hey guys!
 
The weather is already nice enough for the plants to be outside here. It's so nice actually, that my soil temps inside the pots are climbing to 30 C (86 F) already. That is dangerously close to being too high, so I would like to ask you guys and gals some pro tips about keeping those temps down. Is there some type of mulch better than others for this? Should I paint my pots white? What do those of you in the hotter climates do? Unfortunately I can't plant in ground this season, because of the uncertainty of possibly moving to a different house.
 
 
Thanks!
 
There's a few things you could do:

-if you haven't potted up to final containers yet, I'd pot up to white ones (I use 5 gallon buckets)
-paint your pots white (like you said)
-I've heard of some people wrapping their black pots in foil (reflective), or even a regular white kitchen trash bag
-lean up some plywood squares against your pots to absorb and block the sun

Best of luck!
 
There are a few things I've heard of that I'm going to try this summer. I second MikeUSMC with using white pots, but you can even take it a step further and use white grow bags that both reflect light and use evaporation to help cool the roots and soil. A good layer of mulch with be valuable as well, I currently am trying coco fiber since I don't have access to pine straw or grass clippings, and the wind here is too strong for light mulches like straw or alfalfa. The last thing I'm going to try is a 40% shade cloth, I only just purchased it and don't know how effective it is yet but I am hopeful. 
 
What kind of pots are you growing in? It would take special paint to weather the elements if you are growing in plastic pots.
 
I grow in pots for many reasons, including that I can move them in and out of shelter as I find the need arises. One of the key things I've found is not to leave them directly on rocks or cement (such as a driveway) or anything that absorbs too much heat from the sun. The pots will pick up heat from below, as well as the sun. Raising them off the ground allows for cooling airflow. In hotter climates than where I'm currently at, shade cloth is a must-have.
 
I've had as many as 57 hot pepper plants going at one time, so moving them in and out of shade was a bit of a pain, but I did it. A couple years ago I finally bought a cart to help with that task, so it's much easier now.
 
I switched to white plastic grow bags 5 years ago for just this reason.  The year I discovered my problem I cut up some old white bed sheets and draped them around my pots.  This worked just fine, the difference it made in the pot/soil temperature was amazing.
 
Thanks for the tips people! I have terracotta colored plastic pots right now, and just have access to regular white spray paint. Never thought of the fact that stone also gives off heat to the pots! Wonder what I could use to lift them off the floor a bit. Maybe I can get some pallets somewhere!
 
Some good tips!  I live in South Carolina and we had a lot of 95+ degree days.  One suggestion I would add (if it hasn't already been mentioned) is shade cloth.  You can rig it up easily over couple poles and different clothes will give you varying amounts of protection.  Good luck!
 
Mike
 
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