How to Repot a Houseplant

Written & researched by Elena Marsh Gardening & Landscaping Editor

Updated October 2026

The short answer: repot when roots come out of the drainage holes, water runs straight through, or growth has stalled in good light — not on an annual schedule. Go up one pot size only, two inches wider in diameter. Loosen or score any circling roots, cut away anything brown and mushy, use a fresh fast-draining mix, water once thoroughly and then leave it alone for a week or two. Early spring is the best window.

Repotting is done more often than it needs to be and more aggressively than it should be. Most houseplants are perfectly content slightly snug, and a great many are killed by being promoted into a pot three sizes too big out of kindness. The technique below is short; the judgment about when and how far is the part that matters.

We never buy or physically handle the products mentioned here — recommendations come from aggregated owner reviews and horticultural consensus, described in how we rank. The full care picture is at the houseplants and indoor greenery hub.

Four Signs It Is Time — and Four That Are Not

Genuine signals:

• Roots out of the drainage holes, or a visible mat of roots circling on the soil surface.
• Water runs straight through in seconds and the pot barely gains weight. There is more root than mix left in there.
• Growth has stalled through spring and summer in good light with normal feeding — the plant has run out of room to expand.
• It dries out every two days, or it is top-heavy enough to tip over when the mix is dry.

Not signals: the plant is drooping (check water and light first); the leaves are yellowing (usually a watering or light problem, walked through in yellow leaves on houseplants); it has been a year (irrelevant); you just brought it home from the store (leave it two to four weeks to acclimate first, unless the mix is soaked and smells sour).

Typical intervals, once you know what to look for: fast growers such as pothos, philodendron and monstera every 12 to 18 months; medium growers such as rubber plants, dracaenas and peace lilies every two to three years; slow growers such as snake plants, ZZ plants and most cacti every three to five, and both of those last two actually flower and grow better when a little crowded.

Why One Size Up, and Only One

Pot volume grows fast. Going from a 6-inch pot to an 8-inch roughly doubles the amount of mix, and a jump from 6 to 12 inches multiplies it several times over. The plant's water uptake, meanwhile, has not changed at all — it still has the same roots and the same leaves.

The result is a large mass of mix that no root is drinking from. It stays saturated for weeks, air cannot get into it, and the roots that do venture out meet an airless, sour environment and rot. This is not a marginal effect; oversizing is one of the two or three most reliable ways to kill a healthy houseplant, and it presents identically to overwatering because functionally that is what it is.

Material is a real choice, not decoration. Unglazed terracotta breathes and dries a root ball in roughly half the time of plastic, which suits succulents, cacti and anyone with a heavy hand on the watering can. Glazed ceramic and plastic hold moisture much longer and suit ferns, calatheas and anyone who travels. Whichever you pick, it must have a drainage hole — and the classic layer of gravel in the bottom does not substitute for one. Coarse material under fine mix actually raises the saturated zone rather than draining it, which is the opposite of the intended effect.

The Method

1. Water the day before. A moist root ball slides out cleanly and holds together; a bone-dry one crumbles and tears fine roots.
2. Get the plant out gently. Tip the pot on its side, support the base of the stem between your fingers, and slide it out. If it sticks, squeeze a plastic pot all around or run a clean knife between the mix and the wall. Never pull on the stem — you will separate the plant from its roots.
3. Read the root ball. Healthy roots are firm and pale — white, cream or tan depending on species — and smell like soil. Rotting roots are brown or black, soft, and pull apart between your fingers with a sour smell.
4. Do the root work. Tease the outer inch of a circling root ball loose with your fingers. If it has matted into a dense shell, score four shallow vertical cuts down the sides with a clean knife — this is standard practice and it triggers new branching roots outward instead of round and round. Cut away every soft brown root with clean scissors. If you remove a substantial share of the roots, trim a comparable share of the foliage so the remaining roots are not asked to support more leaf than they can supply.
5. Part-fill the new pot so the top of the root ball will sit about half an inch to an inch below the rim — that gap is what stops water sheeting over the edge instead of soaking in.
6. Center the plant at the same depth it was growing. Burying the stem deeper is a common and avoidable cause of stem rot. The exception is a leggy plant with aerial roots, which can go slightly deeper on purpose.
7. Fill around the sides, tapping the pot on the bench to settle the mix rather than compacting it hard with your thumbs. You want it firm enough that the plant stands up and loose enough that water and air move through.
8. Water thoroughly once, until it runs from the drainage hole, then empty the saucer.

Choosing the Mix

Straight bagged potting soil is the default choice and the wrong one for most indoor plants. It was formulated for outdoor containers that dry in sun and wind; indoors it stays saturated for a week or more. Opening it up is the single cheapest upgrade in houseplant care.

Use fresh mix rather than reusing old. Spent mix has lost its structure, compacts around roots, and carries whatever pathogens and fungus gnat larvae were living in it — see getting rid of fungus gnats if that is already a problem in your house. The bagged options and what owners think of them are compared in best potting mix for houseplants.

If You Find Root Rot

Brown, mushy, foul-smelling roots mean stop and change plans. Rinse all the old mix off the roots under lukewarm water so you can see what you are dealing with. Cut back to firm, pale tissue with clean scissors, sterilizing the blades between cuts if the rot is extensive. Remove foliage in rough proportion to the roots you removed.

Then — counterintuitively — repot into a pot the same size or smaller, never bigger. A reduced root system in a large volume of wet mix is exactly the condition that caused the rot. Use fresh, gritty, fast-draining mix, water lightly, and put it in bright indirect light. Do not fertilize until new growth appears, which usually takes three to six weeks.

The underlying cause is almost never a single mistake with the watering can. It is a compounding one: too little light, so slow drying, so wet mix, so no oxygen at the roots. Fixing the pot without fixing the light just resets the clock. Start with how much light do houseplants need, then how often to water houseplants.

Aftercare and Transplant Shock

Expect a week or two of drooping or sulking, particularly if roots were disturbed. It is normal and it resolves on its own if you resist doing anything about it. The rules for that fortnight:

• Same light as before, or slightly less. A brighter spot increases water demand from roots that are not yet supplying it.
• No fertilizer for four to six weeks. Fresh mix already carries nutrients, and feeding damaged roots burns them.
• Water only when the top inch is dry. Fresh mix in a slightly larger pot holds more water than the old setup did, so the interval will naturally lengthen. Watering to the old rhythm after a repot is a very common way to follow one problem with another.
• No drafts, no radiators, no afternoon sun through glass.
• Give it three weeks before concluding anything. If it is still declining after that, tip it out and look at the roots.

One final option worth knowing: for a large plant in a pot you cannot practically size up, top-dressing does most of the job. Scrape off the top two inches of tired mix, replace it with fresh, and feed through the growing season. Mature floor plants can run happily like that for years, which is exactly how commercial interior landscapers keep a ten-foot ficus in the same planter for a decade.