Signs that a plant needs to be repotted are: roots extending out of the drainage holes from a plant container or exposed on top of the soil. Other signs that a plant needs to be repotted are: soil that dries out quickly after watering, water sitting on top of the soil after watering, yellow or stunted leaves.
Use new soil when planting to ensure that it is clean of parasites, bacteria, or fungi. Containers should have been washed in soapy water prior to putting plants in them. Clay pots should be immersed in water for 30 minutes prior to using. These containers are mostly suitable for succulents and cacti since they draw moisture from the soil. Attention has to be given to plants in these containers since they dry out quicker.
Pick a container that is 1-3″ larger in diameter than the current one that the plant is in. This depends on the growth rate of the plant and general health. If the plant grows at a fast rate or is large, then a container 3″ larger than the current one is best. Work in an area where there is sufficient space and lay down newspapers to catch the soil.
Remove the plant form the container by supporting it at the base with one hand while tapping the container on the underside with the other hand. This should loosen the plant and help it slide out of the container. Sometimes, when the roots are impacted and get struck to the container, it is necessary to slide a knife all around the container and as deep as possible.
Gently squeeze the rootball to loosen it and untangle the roots with your fingers if necessary. Use pruning shears to trim the roots. Remove any dark, soft, and mushy roots. Roots should be shades of white or light gray and should not have bad odors.
Place pebbles or a coffee filter on the bottom of the new container to keep the soil from running through. This also protects against water and nutrients from leaching out too quickly.
Place soil into the pot filling bottom to about 1-2″ and press down firmly to rid of air pockets. Do not press too hard as this may damage the roots. Getting rid of air pockets ensures that water doesn’t flush out allowing proper intake by the roots.
Place the plant into the container and fill with soil around the plant, gently pressing on the soil while supporting the plant. There should be about 1″ of space from the soil to the top edge of the container and the rootball shouldn’t be much deeper than it was in the original container.
Water the plant and place in a well-lit area without direct sunlight or extreme temperatures. The plant might suffer from a little shock but will do well in a matter of weeks.