Most houseplants need a bigger pot less often than people expect. Many grow fine with their roots a little crowded, and a pot that's too big causes more trouble than one that's a few months too small. Check the roots before you buy a new pot. If they've filled the old one, repot in late winter or spring, into a pot only a little wider.
Signs a plant needs a bigger pot
A few signs show from the outside:
- Roots growing out of the drainage hole. Treat it as a cue to slide the plant out and look.
- The mix dries out within a day or two of a thorough watering, and the plant wilts again soon after. A pot full of roots holds very little water.
- Growth has slowed in spring or summer, even with good light and regular feeding.
- The plant is top-heavy and tips over, or the pot is bulging or cracking.
- The mix has sunk well below the rim. Potting mix breaks down and slumps over a few years, and it drains less well as it does.
To check, water the plant an hour or so beforehand so the root ball holds together. Skip that if the mix is already damp, or if it's a succulent, cactus, snake plant or ZZ plant. Turn the pot on its side, support the base of the stems between your fingers, and slide the plant out. If it's stuck, tap the rim on the edge of a table or run a knife around the inside of the pot. Don't pull it out by the stem.
| What you see | What it means | What to do |
|---|---|---|
| Roots wrapped around the outside of the root ball, little mix showing | Root-bound | Repot, ideally in spring |
| Roots reach the sides, but you can see mix between them | Fine for now | Put it back and check again next year |
| Roots poking out of the drainage hole | Often root-bound | Slide it out and look |
| Mix shrunk away from the pot, water runs straight through | Root-bound, or the mix has dried out hard | Soak from below, then check the roots |
| Roots brown and soft, or smelly | Root rot | Trim and repot into a smaller pot |
| Mix sunk, crusty or breaking down, roots fine | Old mix | Fresh mix, in the same pot or one size up |
Water rushing straight through a pot has two common causes. Roots may have filled it, or the mix may have dried so far that it shrank from the sides and repels water. For the second, stand the pot in about 2 inches (5 cm) of water for half an hour to an hour, until the surface of the mix feels damp. If it still dries out within a day or two after that, look at the roots.
Brown, mushy roots are a different problem. A plant with root rot needs the rotten roots cut away and a pot only just big enough for what's left, and moving it to a bigger pot makes things worse. How to save a plant from root rot covers that rescue.
How often to expect it
Fast growers such as spider plants may need repotting every year or two. Slow growers often go two or three years, and big floor plants in large pots can go longer. Those are rough guides. Slide the plant out once a year in spring and let the roots decide.
Some plants are happy in a snug pot and only need moving up once they've completely filled it:
- Snake plant can stay in the same pot until the roots and leaves have filled it or the pot starts to bulge.
- Christmas cactus blooms best when it's a little root-bound. Move it up only once the roots fill the pot, and not while it's in bud or flower.
- Clivia often flowers better with its roots a little crowded. Every three to five years is enough.
- Amaryllis does well root-bound.
- Hoya can stay in its original pot for several years.
Moth orchids are a separate case. They like a pot just big enough for their roots, but they still need repotting about every two years, because the bark they grow in breaks down and holds too much water. The orchid article covers what old bark looks like.
The best time of year
Repot in late winter or spring, as the plant starts putting out new growth. Early summer is fine too. In fall and winter, growth slows or stops and disturbed roots take longer to recover. If the plant is in bud or flowering, wait until it has finished.
Sources differ on how strict to be. Some extension services say indoor plants can be repotted at any time of year, and tough, fast growers like spider plants and peace lilies handle an off-season repot well. Root rot, a cracked pot, or a plant so top-heavy it keeps falling over shouldn't wait for spring at all.
If you find a slower grower root-bound in October, it can usually wait. Check the mix more often and water when it's dry, even if that's more often than usual. Or replace the top inch or two (2.5–5 cm) of mix (see below), and do the full repot in spring.
How much bigger the new pot should be
Go up 1–2 inches (2.5–5 cm) in diameter, and not much deeper. For pots larger than about 10 inches (25 cm), you can step up a little more, but keep the new pot no more than a third wider than the old one.
| Current pot | New pot |
|---|---|
| 4 in (10 cm) | 5–6 in (13–15 cm) |
| 6 in (15 cm) | 7–8 in (18–20 cm) |
| 8 in (20 cm) | 9–10 in (23–25 cm) |
| 10 in (25 cm) | 12 in (30 cm) |
Roots only take up water from the mix they reach. Mix past the roots stays wet for days after each watering, and roots sitting next to wet mix are the ones that rot.
A few more things about the pot:
- It needs a drainage hole. If you like a decorative pot without one, keep the plant in a plastic pot inside it and tip out any water that collects after watering.
- Terracotta dries out faster than plastic. Plants in clay pots need watering more often, which suits plants that hate wet roots and is less good for ones that like to stay evenly moist.
- Skip the gravel at the bottom. It doesn't do the job of a drainage hole, and it takes up space the roots could use. A piece of mesh or a coffee filter over the hole is enough to keep the mix in.
How to repot
- Water an hour or so before. A moist root ball slides out in one piece. Skip this for succulents, cacti, snake plants and ZZ plants, which you repot dry.
- Slide the plant out as described above.
- Loosen the roots. Tease circling roots away from the root ball with your fingers. If they've grown into a solid mat, cut shallow slits down the sides of the root ball in three or four places with a clean knife. Trim off any roots that are dead or mushy.
- Use fresh potting mix (fresh bark for orchids), never soil from the garden, which packs down and drains poorly in a pot. Put enough in the bottom of the new pot that the top of the root ball sits ½–1 inch (1–2.5 cm) below the rim.
- Fill in around the sides and firm the mix gently. Don't pile new mix over the top of the old root ball.
- Water until it runs out of the bottom, then empty the saucer. Succulents, cacti, snake plants and ZZ plants are the exception: repot them into dry, gritty mix and wait a week to ten days before watering, so any broken roots can seal over first.
- Go easy on it afterward. Keep the plant in bright, indirect light for a few days, out of direct sun. Hold off on fertilizer for a few weeks, until you see new growth.
When you don't want a bigger pot
Some plants are already as big as you want, or in the largest pot you have room for. Those can stay put with fresh mix.
- Top-dress. Scrape off the top 1–2 inches (2.5–5 cm) of mix and replace it with fresh. For a large floor plant, take off 2–3 inches (5–8 cm) every other year or so. This also removes the white crust of salts that builds up on the surface from tap water and fertilizer. To clear salts from the rest of the pot, run plenty of water through it and let it drain.
- Root-prune. In spring, slide the plant out, trim away up to a quarter of the outer roots, and put it back in the same pot with fresh mix around the sides and bottom. The plant gets new mix and room to grow without getting any bigger.
The quick checklist
- Roots out of the drainage hole, or the pot drying out within a day or two → slide the plant out and look.
- Roots wrapped around the root ball → repot. Mix still visible between roots → wait a year.
- Roots brown and soft → that's root rot. Trim them and go smaller.
- Repot from late winter to early summer, not while it's flowering.
- New pot 1–2 inches (2.5–5 cm) wider, with a drainage hole. Never jump several sizes.
- Fresh potting mix, root ball ½–1 inch (1–2.5 cm) below the rim, water through. Succulents go in dry and wait a week to ten days.
- A few days out of direct sun, no fertilizer until new growth.
- Want it to stay the same size → top-dress or root-prune instead.
Common questions
Should I repot a plant as soon as I bring it home?
Usually not. A plant fresh from the store has just been through a move and a change of light, and most don't need a bigger pot in their first year. Repot sooner only if it's clearly root-bound when you slide it out, or the pot is cracked or has no drainage hole.
Can I repot in fall or winter?
You can, and some extension services say indoor plants can be repotted at any time of year. Spring is still the better choice, because the plant is starting to grow and replaces disturbed roots faster. Root rot, a broken pot or a plant that tips over every time you touch it are reasons not to wait.
Can I put a small plant straight into a big pot so I don't have to repot again?
Better not. The roots can only take up water from the mix they reach, and the rest stays wet for days, which is how root rot starts. Signs of a pot that's too big are yellowing or browning leaves, wilting, and mix that still feels soggy long after watering. The fix is to move the plant back down into a pot only just bigger than its roots.
Why is my plant drooping after I repotted it?
Repotting breaks some of the fine roots that take up water, so a little drooping in the first days is common. Keep the plant out of direct sun for a few days and don't feed it. If it's still drooping after a couple of weeks and the mix is staying wet, the new pot may be too big, or the roots may have been rotting before you started.
Related articles
How to save a plant from root rot
While there are still firm roots to work with, you can save a plant from root rot: cut away everything brown and soft and repot into fresh mix in a smaller pot. If almost nothing firm is left, take cuttings instead.
Why are my pothos leaves curling?
Pothos leaves usually curl because the pot has gone too dry, and they flatten out again within a day or two of a good soak. If the soil is already damp, look at the roots, the sun, and the undersides of the leaves instead.
Why is my rubber plant dropping leaves?
Rubber plants answer almost any change by dropping leaves, so the place to start is what changed around the plant in the last month or two. How to tell adjustment from root rot, cold, and the rest.
This article was researched and written with AI assistance and reviewed by a human editor before publishing. How we use AI