House plants are quite likely to have outgrown their pots if they have spent the summer outdoors growing in ideal locations. The same could have happened if they remained indoors in the long days with bright light and higher humidity that brings substantial growth.
As a consequence, your plants may face the winter in a container that was roomy enough last spring but is now too small. Spring is the ideal time for repotting house plants so that roots can develop during the summer. But plants certainly can benefit from larger quarters in the fall.
In any case, whether they are repotted or not, plants that vacationed outdoors and are then brought into the house should be checked for insect pests, slugs, sow bugs or earthworms that may have invaded the pot and remained in hiding.
Removing Your Plant From Its Pot
To remove a plant from a small pot, turn it upside down, tap the top edge on a bench or chair edge, holding one hand under the soil ball so it rests in your hand as it leaves the pot. This prevents damage. Check the base of the soil ball for channels where pests might hide. Then carefully place the root mass into a larger pot and tap so that the root ball settles in.
Try to disturb the roots as little as possible during fall repotting. Spring potting is ideal for your plant’s health. If a soil change is necessary, do it as growing conditions improve. In fall, the main purpose for repotting is to move the plant into a slightly larger pot to bring it into visual balance and to reduce the frequency of watering needed in the warm, dry atmosphere of the average home.
Preparing Your Plant’s New Home
Use clean pots in repotting. It is best also to shift plants into pots only one size or so larger than the previous pot. The most common houseplant pot sizes are 4, 5,6,8,10 and 12 inches. Most pots are standard shape but a pot more shallow in depth, called the “azalea” pot, is often used.
Previously used pots should be washed thoroughly with soapy water. To sterilize, soak the pots in a solution of one part liquid bleach to nine parts warm water. If the pot has a white accumulation of salts on the top or outside, use a wire brush to remove it.
Place a few pieces of broken pot or stones over the drainage hole when potting house plants to prevent the new soil from being washed out. The pot pieces also should be cleaned.
Potting mixes – there are many good ones available in garden shops – should provide proper drainage and air movement for roots. If plants are root bound, cut some of the encircling roots to stimulate growth of new roots into the new mix. Try not to break the existing root ball.
Put enough of the new soil in the base of the pot so that the plant will sit in the larger pot at the same height as the old pot. Fill in around the sides of the existing root ball with new soil, firming the mix as it is added.
As for watering, give plants enough so that water seeps from the holes in the pot bottom, but remove any excess after an hour or two. Your plant should be ready for a long, hard winter.