Move a root-bound plant into a pot 1 to 2 inches wider than the old one, and do it in spring.
A pot that is too big keeps the mix wet for too long, and the roots suffer.
Signs your plant needs a bigger pot
Illinois Extension lists several signs. Roots growing out of the drainage holes is, on its own, a sign it is time to repot. The others are easy to check:
- Roots appear on the soil surface.
- The soil mass is filled with roots.
- New leaves are smaller than normal.
- The plant wilts between normal waterings.
To be sure, slide the plant out of its pot and look. A mat of roots circling the outside of the root ball means it’s root-bound, and it’s time to move up.
Pick the season
Repotting works best when the plant is actively growing.
Plan on early spring. It’s typically done in spring or early summer, and most gardeners have the best success in late winter or early spring.
How much bigger the new pot should be
Move up one pot size, which means a container 1 to 2 inches larger in diameter.
Putting a small plant into a large pot leaves the soil too wet for too long. An excessively large soil volume can lead to root rot, because the plant can’t use the available water.
Go up one size, not three. For your own pot, stay with the 1 to 2 inch rule for pot size.
Repot in seven steps
- Water the plant about an hour before. Illinois Extension recommends this so the plant is hydrated.
- Choose a pot with a drainage hole. If it’s a reused pot, scrub it, dip it in a 10 percent bleach solution, then rinse it with clean water.
- Knock the plant out of its container and look at the roots.
- Cut or unwind any circling roots, so there is no dense mat on the outside of the root ball.
- Fill with fresh potting mix, not soil from the yard. Do not put gravel or grit in the bottom.
- Set the plant at the same depth it grew in the old pot, with the top of the soil about an inch below the rim. Anything from a quarter inch to an inch leaves room for watering and plant growth.
- Firm the mix around the roots and water right away.
Aftercare and the droop
Repotting can be quite stressful for a plant, and it needs enough time, adequate water and the right light to re-establish.
Judge the droop by the plant, not the calendar.
If the plant keeps wilting in wet mix, check the roots for rot and follow the rescue steps.
Skip fertilizer for now. Wait at least 2 to 4 weeks before regular fertilizing starts again.
When you don’t need to repot
Some plants need repotting each year, while others may not need it for many years.
Most houseplants prefer a root ball in slightly cramped quarters, so frequent repotting is not always needed. Dividing a plant into several smaller ones is a separate job from repotting.
Once it has settled, watch for new leaves at normal size and no wilting between normal waterings.
