When your plant outgrows its home
How do you know when a plant needs to be repotted?
A rootbound plant in a pot that's too small is a prime candidate for repotting. How can you tell? There are three symptoms to look for:
- Water runs out of the drainage hole too quickly. This means that the soil in the pot has become replaced by roots!
- The roots are growing out of the drainage hole.
- The entire plant is top-heavy. A good rule of thumb is that your container should a diameter of one-half to one-third the height of the plant.
When repotting, line a table with newspaper for easy cleanup, and arrange your materials so you can work quickly. Plants can go into shock once you've removed them from the soil, so make the transition a speedy one for best results.
The first step for re-potting is to prepare your plant's new home. The pot should be one size larger than its current container, allowing an inch or two for growing room on the sides and the bottom. Cover the drainage hole with clean rocks, a shard of terra cotta, a coffee filter, or a screen to keep the hole from becoming plugged. Fill the pot with a couple of inches of fresh potting soil.
To get your plant out of the old pot, ease your trowel around the edge of the pot to loosen the soil. Tip the pot and guide the plant out. If the plant has become root-bound, or its roots are knotted at the bottom, gently break off the knot and loosen the roots with your fingers.
Now you're ready to re-plant. (See articles on "planting" for more details.) You can mix dry fertilizer into the potting mix when you plant the plant, but wait a few weeks before adding liquid fertilizer, to avoid risk of root burn. Once your plant is in its new home, water it thoroughly. Do not water again until the soil is almost dry, to prevent any damaged roots from rotting.