Houseplants have to be repotted periodically to allow room for root systems to expand. Repotting prevents plants from becoming pot-bound and improves water retention, which in turn increases time between waterings.
Some indications that a plant needs to be repotted are frequently wilting leaves, yellowing leaves near the bottom of the plant, roots visible near the surface or coming out of the drainage holes.
When to repot
The ideal time to repot an indoor plant is late-winter through spring. Just like the plants in your garden, the increasingly longer days of early spring stimulate a period of growth in houseplants, both above and below the soil. By repotting in late-winter you're giving your plant room to expand its roots just as they're becoming more active.
How often you repot a plant depends on how fast the plant grows. In general fast growing plants need to be repotted more often, usually about once a year, while slower growing plants can usually remain in the same pot for 2-3 years.
How to repot
Repotting is a relatively easy maintanance task, however following these simple guidlines will help you avoid common mistakes.
- Remove the plant from its pot and gently disturb the root system so that roots are not in a tight rootball. If the roots are too tight to loosen, lightly score the rootball with a knife to loosen them.
- Select a pot that is no more than 2-4 inches larger in diameter than the current pot. If the pot is too large in relation to the plant, the soil will dry out slowly and it will be difficult to control the moisture. The top of the soil may be dry to the touch while the soil in the center of the pot may still be wet.
- Place a small piece of broken clay pot over the drainage hole to prevent soil from washing out. Do not add a layer of clay pieces or rocks because this may slow water movement through the pot.
- Select an all-purpose potting mix for the plant. Place enough dry potting mix in the bottom of the pot so that the top of the rootball is within 1 inch of the container top. Do not add soil above the original level on the rootball.
- Fill around the rootball with mix. Pack the soil by gently pressing with your fingers. Water well so excess water drains out of the pot. Repeat as many times as necessary until the soil becomes thouroughly moist.