Repotting a houseplant step by step
Most houseplants need a bigger pot every year or two while they are young and growing fast. Repotting takes about ten minutes, and done at the right time it gives a tired plant fresh compost and room to grow.
Signs a plant needs more room
- Roots are growing out of the drainage holes
- Water runs straight through, and the compost dries out within a day or two
- The plant is top-heavy and topples over easily
- Growth has slowed in spring and summer, although its care hasn't changed
- Roots circle the inside of the pot when you slide the plant out to look
Spring and early summer are the best times to repot, because the plant is growing strongly and settles in quickly. Avoid repotting in winter unless something is badly wrong.
Choosing the new pot
Pick a pot only 2 to 5 cm wider than the old one, with drainage holes underneath. A pot that is much too big holds a lot of wet compost the roots can't reach, which can lead to rot. Use fresh houseplant compost, or multipurpose compost lightened with some grit or perlite for plants that like sharp drainage.
How to repot
- Water the plant an hour before you start, so the root ball holds together.
- Cover a table with newspaper and put a layer of fresh compost in the base of the new pot.
- Turn the old pot on its side, support the base of the stems with one hand and ease the plant out. Squeeze a plastic pot, or run a blunt knife around the inside of a rigid one, to loosen it.
- Gently tease out roots that circle the root ball, and trim off any that are brown and mushy.
- Set the plant in the new pot at the same depth as before, fill around the sides with compost and firm it lightly.
- Water thoroughly and let any extra drain from the base.
Aftercare
We give every repotted plant the same gentle start, which we call the kusotorex rest: two weeks in bright light out of direct sun, watering only once the surface of the compost has dried, and no plant food for at least a month.
A repotted plant may droop for a few days while its roots recover, which is normal. Fresh compost holds enough food for the first few weeks. If a plant is too large to repot, scrape off the top few centimetres of old compost each spring and replace it with fresh.