I suspect that many of you are growing plants in black plastic pots. The reason, or course, is that they are free. Whether they are small 4 inch square pots or 3 gallon round ones, there is always a free source for these containers. My main source is the Redwood Barn nursery in Davis. Customers constantly return used pots to the nursery for re-use. My concern is that you remember that these black pots are easily heated by the sun, and root damage can result. Even though the sun’s rays are less intense in the Winter, the rays are coming in at a lower angle and strike the sides of your pots more directly. The air is cooler now, but the sun can still release a great deal of heat into the soil of your potted plants.
If you are growing plants that prefer full sun, you can still use various techniques to shade the pots. I’ve shown one of these below where I have clamped shade cloth in front of the black pots. Hopefully you have a more esthetic technique in practice. Notice that the white pots on the end have no sun shield because they naturally reflect the sunlight and don’t convert it into heat. So, if you wish to avoid the whole problem, use white pots. I noticed that Amazon has a great selection from 3 inch to 7 gallons. White pots show plants better anyway, don’t you think?
By the way, LaVille plants most of her “mother” plants for propagation in white pots—pots that will not go to sales by accident.
Stan, The Cool Man
White pots and shielded pots