Cover with Fabric 
N-sulate fabricWhile the Sacramento Region may be considered as having a Mediterranean climate it has it’s highs and lows to contend with. The temperatures soar to over 90 degrees daring much of the summer while it is common to have freezing temperatures in the winter.
Here are some simple solutions to help you help your plants.
HEAT!
In the summer there are two very effective methods to keep your plants cool.
- Provide shade during the heat of the day or at least filtered sunlight.
- Remember how an animal will lie belly down on the ground when it is hot. That is because the soil is much cooler than the air temperature.
- Do the same with your potted plant. Place the pot directly on a sheet of plastic which is laid upon the soil. The plastic will not allow the plants to root into the soil. Mulch between the pots with ground bark to help retain moisture.
COLD!
TrellisMost all Pelargoniums will suffer from freezing temperatures. Erodiums and Hardy Geraniums are relatively frost tolerant and only show signs of dormancy. Place the potted plants as close to the exterior wall of your home as you can and use the protective fabric described below.
Your home radiates a great deal of heat, use it to your benefit, you’ve already paid for it. For those plants grown in the ground there is still hope.
New light weight fabrics have been created to cover and insulate the plant from those extremes.
N-Sulate, the manufacturer, has invented a very flexible and light weight fabric which is most often sold in sheets 12 feet x 10 feet size in a roll.
It may be sold under a variety of brand names but is usually available at your local nursery. Cut the sheet into whatever sizes are necessary to completely cover the plant or plants flush to the ground. A single layer will provide 3 to 4 degrees of protection.
Rule: one layer for temps down to 290, two layers for temps down to 260 and so on. I also recommend that you erect a support to bear the weight of the frost cloth unless your plant is very bushy and can support the weight. A tomato plant hoop trellis is perfect for the job, after all, it’s not being used in the winter months. Remove the frost cloth once the temperature warms to above 343 the plants need sunlight too.