A succulent doesn't need a new pot simply because another year has passed. Many grow well in fairly snug containers and can be damaged by a move into a huge pot of wet compost. The reason to repot is usually that the roots have filled the available space, the growing mix has broken down or the plant has become unstable.
The Royal Horticultural Society advises repotting most indoor cacti and succulents in spring when they need more space. Use a container with drainage and a gritty, free-draining growing medium. Those two choices matter more than choosing a particularly attractive decorative pot.
Why spring is usually best
Spring is a convenient time because most ordinary dry-climate succulents are entering active growth. That gives their roots a better opportunity to establish in the fresh compost.
Winter is less suitable for unnecessary disturbance. Many plants grow slowly in cool, short days and use less water. A freshly repotted succulent in a large wet container can sit in damp conditions for too long.
There are exceptions. Some succulents follow unusual seasonal growth cycles, and rainforest cacti have different care needs. Identify the plant where possible rather than treating every fleshy-leaved houseplant as identical.
Choose a pot only slightly larger
Select a clean container that comfortably accommodates the root ball with a modest amount of extra space around it. A dramatic increase in diameter creates a reservoir of compost that may remain damp after the roots have used the water they need.
Drainage holes are essential for ordinary container-grown succulents. A stylish sealed pot can be used as an outer cover, but keep the plant in an inner pot that drains and empty standing water after watering.
Terracotta is popular because it can release moisture through its walls. Plastic pots retain moisture for longer and are also suitable when the watering routine matches them. Neither material is a substitute for the right compost.
Check the stability of the finished arrangement. A tall succulent may need a heavier pot or broad base instead of simply a deeper container.
Use the right succulent compost
Most common indoor succulents prefer an airy, sharply draining medium. The RHS recommends a proprietary peat-free cactus compost or a mix of two parts peat-free John Innes No. 2 and one part horticultural grit or sharp sand.
Use horticultural materials sold for plant-growing rather than ordinary building sand. The aim is to keep enough air in the root zone and prevent fine compost from staying saturated.
An ordinary rich houseplant compost alone often holds more water than desert-type succulents prefer. Don't rely on a thick layer of stones at the bottom to solve poor drainage. Use a pot with holes and a suitable mix throughout.
Clean the container before starting, particularly if it previously held a diseased plant. Loose old roots or decaying compost in the pot are not useful ingredients.
Remove the plant carefully
Let the compost reach a manageable moisture level before handling it. Extremely wet compost falls apart and makes damaged roots harder to see, while bone-dry, solid roots can be brittle.
Tip the pot and ease the root ball out without pulling firmly on leaves or stems. Squeeze the sides of a flexible nursery pot if needed. If roots have grown out through the bottom, tease them back gently where practical.
For spiny cacti, use thick folded newspaper, sturdy gloves or an appropriate handling tool. The RHS recommends folded newspaper as a way to grip prickly plants without grabbing the spines directly.
Protect yourself from irritating sap too. Some succulents, particularly euphorbias, have milky sap that can irritate skin and cause serious eye injury. Wear gloves and avoid touching your face.
Inspect the roots before planting
Healthy roots vary among species, but they should generally be reasonably firm. Remove loose exhausted compost from the outer root ball and check for rotting or badly broken material.
Don't strip every healthy root bare just to make the result look clean. That may cause more damage than the plant needs. If the roots are circling tightly, loosen only what is necessary so they can extend into the new mix.
Clearly dead or rotten sections can be removed with clean tools. If there is extensive decay, identify the cause and consider an appropriately small pot for the remaining healthy roots.
The RHS does not recommend a universal procedure of soaking every succulent immediately after handling damaged roots. Aftercare should reflect the species and how much disturbance occurred.
Set the succulent at the right depth
Place a little fresh compost in the bottom, then position the root ball so the plant sits at about the same level as before. The crown should not be buried under damp compost.
Add mix around the sides and tap the pot gently to settle it. Firm lightly with your fingers without compacting every air gap. Leave some space below the rim so later watering doesn't spill over the edge.
If the plant has a rosette of thick leaves, keep compost away from the leaf centre. Material trapped inside the crown can hold moisture where the plant is vulnerable to decay.
A thin grit top-dressing can look tidy and limit compost splashes, but it is optional. It should not be piled over the growing point.
When should you water after repotting?
The answer depends on root condition and the succulent type. A healthy plant transferred with minimal disturbance may be watered according to its normal growing-season needs. A plant with roots that have been cut back or serious rot needs more cautious care.
Never treat repotting as a reason to soak a succulent every day. The growing mix needs to dry suitably between waterings, and the root system must have enough air to function.
The RHS recommends watering most desert-type succulents while actively growing, then greatly reducing the amount in winter. Rainforest cacti and other exceptions are different, so check the exact plant's guidance if you can.
After watering, let all excess water run away. Don't leave the pot standing in a water-filled saucer overnight.
Aftercare for the first few weeks
Return the plant to a bright position suitable for its species. Some succulents enjoy direct sunshine, but suddenly moving a plant from a shaded shelf into intense midday sun can scorch its leaves.
Avoid strong fertiliser immediately after repotting if the fresh compost already contains nutrients. Watch the plant rather than trying to accelerate recovery with extra feed.
A few leaves may soften slightly after disturbance. That doesn't mean water is always the answer; check the compost and roots before changing the routine. Continued collapse at the base is a reason to investigate decay.
Don't keep lifting the plant to check new roots. Give it a stable place and enough time to settle.