How to Repot a Houseplant
Repotting gives houseplants fresh growing medium and more room when they have outgrown their container. It can also improve drainage and refresh compacted compost.
But repotting is not something every plant needs every year. In many cases, the best time is when the plant is actively growing and there is a clear reason to repot.
When should you repot a houseplant?
Look for:
- Roots filling the pot or emerging from drainage holes
- Compost that has become compacted or degraded
- Water running straight through the pot
- A plant drying out unusually quickly
- Poor growth despite suitable light and care
- A plant becoming unstable or top-heavy
At Thompsons we advise repotting when needed, your houseplants compost can degrade and compact over time. We suggest potting on in spring, with the next pot being slightly larger in diameter than the last. (5-10cm)
What you need
- A clean pot with drainage holes
- Suitable peat-free houseplant compost or specialist mix
- Your houseplant
- Clean scissors or secateurs if roots need attention
- A saucer or tray
Step 1: Choose the right new pot
Do not automatically choose a much larger pot. A container that is too large can hold a large volume of wet compost around a relatively small root system. This can increase the risk of root problems.
Choose a pot only modestly larger than the current one.
Step 2: Prepare the plant
Watering immediately before repotting is not always necessary; assess the plant and compost. Work somewhere easy to clean and handle the plant gently.
Step 3: Remove the plant
Support the plant near the base and carefully slide it from its container. Avoid pulling hard on stems or leaves.
Step 4: Inspect the roots
Healthy roots should generally be firm rather than soft and collapsing. If the rootball is tightly packed, gently tease some roots loose.
If roots are dark, mushy or damaged, investigate the cause rather than simply hiding the problem in fresh compost.
Step 5: Add fresh compost
Place enough compost in the new pot so the plant will sit at roughly the same depth as before.
Step 6: Position and fill
Place the plant centrally and fill around the rootball with fresh compost. Do not bury the stem deeper than it was previously planted.
Step 7: Water and settle
Water according to the plant's requirements and allow excess water to drain. Place the plant somewhere appropriate for its light needs while it settles.
How often should houseplants be repotted?
There is no universal timetable. Some plants can remain in the same container for years, while fast-growing plants may need more frequent attention. Check the plant rather than repotting simply because a calendar says it is time.
Avoid overpotting
A common mistake is choosing a pot that is much larger than the old one. Overpotting can leave a large volume of compost wet for too long, reducing aeration around roots and increasing the risk of root problems.
What compost should you use?
Use a good-quality peat-free compost appropriate to the plant. Cacti and succulents generally benefit from a more freely draining mix, while other plants may need a moisture-retentive but well-aerated medium.
Thompson's Garden Centre recommends Miracle-Gro Houseplant Potting Mix, and containers with drainage for houseplants.
Conclusion
Repotting is about giving a plant the conditions it needs, not simply moving it into the biggest pot available. Choose the right container, use suitable compost, protect the roots and continue to monitor watering after repotting.
Related Thompson's guides
• Houseplant Care
• Houseplants for Low Light
• Houseplants for Direct Sun
• Houseplants for Beginners