Potted Plant Therapy
Wintertime will slow outside gardening if you are one of those people who will not go outside if the temperature is lower than your age. But there are other winter gardening activities.  There is something you can do to get your hands dirty and benefit your plants: repot those sad, root-bound plants.
How do you know when a plant needs to be repotted? The easiest way is that if it has never been repotted and has been on your front porch for five years, it is time. Other clues are more physical. Your plant will not look so good and neither will the potting soil. Remove the plant from the pot to check the roots. If the roots have completely filled the pot or are growing out the bottom holes, it is time. If the roots have circled the pot, basically looking like they want to strangle the plant, it is time. If the potting soil will no longer hold moisture and the water just runs down the inside, it is time. If you see accumulated salts, time to check out the potting soil. Winter gardening in a medium warm garage saves your potted plants and saves you from ordering too many seeds from those stacks of catalogs.
You will need pots, potting soil, and cleaners (if you are re-using pots). Your pot should be no larger than two inches wider than the original pot. The pot should have good drainage. The pot needs to be clean to prevent the transfer of diseases. Use a stiff brush to remove salts left over from fertilizing then dip your pot in a solution of one-part bleach to nine parts water. Let the pots dry before adding the plants.
The best potting soils have the optimum parts of nutrients, moisture, air, and stability. These are the conditions that make the best home for potted plants. Quality potting soil will have all the nutrients your plant will require initially.  They will include peat moss and/or finished compost. These materials help to hold moisture and supply nutrients. In combination with either perlite or vermiculite, the potting soil will have aeration. Roots need air and oxygen otherwise they will decay. The balance between aeration and water retention will help to prevent mold or rot and will supply the plant with a drink.  The potting soil also supplies stability or structure for the plant to remain upright.
Potting soil must have a balance. The plant is in a contained environment, so it requires drainage, but also moisture and nutrients, but not so much salt to burn the leaves. The soil requires stability, but not so heavy that the pot is unmovable.
Before starting the change, moisten the potting soil. Depending on the size of the pot, you may either invert it to remove the plant or lay the pot on its side. Tap the pot and the plant should come out easily. If not, you may have to loosen the roots by cutting them back, especially if they are circling the inside of the pot.
Add new soil to the bottom of the pot giving the root ball the same height as in the previous pot. Add new soil along the edges or sides. Do not bury the crown of the plant (where the base of the plant connects with the soil), otherwise, it will create crown rot. Water it, and you are good to go.
By checking your potted plants and repotting them you will add longevity and good health to them. Happy Gardening!
Julie Silva is a University of California Cooperative Extension Master Gardener of Tuolumne County. UCCE Master Gardeners of Tuolumne and Calaveras Counties can answer home gardening questions, call 209-533-5912 Fill out our easy-to-use problem questionnaire here. Check out our website here, You can also find us on Facebook.