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Graptopetalum is not fussy about being pot-bound and grows perfectly well slightly cramped, so repotting is not an annual ritual. Do it when one of a few specific things is true, and otherwise leave the plant alone, because every repot costs leaves.
Repot when roots come out of the drainage hole in quantity, when the compost has broken down to something that stays wet for a fortnight, when the plant has become so top-heavy or so far over one side of the pot that it tips, or when you have just bought it and it is sitting in dense peat-based nursery mix. That last case is the most urgent one and is worth doing within a few weeks of bringing the plant home.
| Situation | Repot? | Reason |
|---|---|---|
| Roots showing through the drainage hole | Yes, next growing season | Root ball is full, growth will stall |
| Compost still damp two weeks after watering | Yes, promptly | Broken-down mix, rot risk through winter |
| Plant tips over when the stems hang out | Yes | A fall costs more leaves than the repot does |
| Newly bought in soft peat-based mix | Yes, within a few weeks | Nursery mix holds far too much water at home |
| Looks crowded but drains well and grows | No | Crowding does not harm it, handling does |
| Stem has gone soft near the base | No, take cuttings instead | Rot has started, the root ball is not worth saving |
Repot in early spring or early autumn while the plant is actively growing, so cut roots heal quickly. Repotting into cold weather, or into the peak of high summer heat, leaves damaged roots sitting in damp compost with no growth to seal them.
Pot shape matters more than pot size
The roots are shallow and fine and never fill a deep pot, and the parts of a deep pot the roots never reach stay wet. A wide, shallow pot or a pan gives the same root volume with far less standing moisture, and it suits the plant's habit, because the stems want to lean out and hang over the rim rather than stand upright.
Go up one size only, an inch (2 to 3 cm) more across than the current pot. A large pot around a small root ball holds water in a ring the plant never touches. Unglazed clay is the safest material because it loses water through its sides, and it is heavy enough to stop a top-heavy trailing plant tipping. Any pot must have a drainage hole; no arrangement of gravel in the bottom substitutes for one.
The mix
Aim for a gritty, open mix that drains within seconds and dries within a week. Graptopetalum is not demanding about nutrition and does not need rich compost; it needs air around the roots.
| Component | Proportion by volume | What it does |
|---|---|---|
| Cactus or succulent compost | About half | Holds a little moisture and some nutrition |
| Pumice, perlite or coarse grit, 2 to 5 mm | About half | Creates air gaps, speeds drying |
| Top dressing of the same grit | Quarter inch (6 mm) layer | Keeps the stem base dry, stops splash marks on leaves |
| Fine sand or standard potting mix alone | Avoid | Packs down and holds water for weeks |
Doing it with the fewest losses
The whole technique is about reducing the number of times anything touches a leaf. Dry compost, a firm grip on the stem and a tray under the whole operation handle nearly all of it.
- Let the compost dry out first Do not water for at least a week beforehand. A dry root ball slides out in one piece and can be crumbled apart with your fingers. A wet one has to be pulled and prised, and every tug shakes leaves loose.
- Work over a tray Whatever you do, leaves will come off. Working over a shallow tray or a sheet of paper means you collect them all instead of hunting on the floor, and almost every one of them will root if you keep it.
- Take the plant out by the stem, low down Grip the main stem just above the compost, between finger and thumb. Turn the pot on its side and tap the rim, or squeeze a plastic pot, until the root ball slides. Never pull the plant out by holding the rosette.
- Tease off the old compost and check the roots Crumble away as much old mix as comes free easily. Healthy roots are pale and wiry. Cut off anything black, hollow or slimy with clean snips, and take the cut back into firm tissue.
- Plant at the same depth, then leave it dry Hold the stem at the height it sat before, trickle mix in around it and tap the pot to settle it rather than pressing down with your fingers. Firm only with a light tap. Then add the grit top dressing.
- Wait before watering Do not water for five to seven days. Cut roots need that time to seal, and water on fresh wounds is the main cause of post-repot rot. After that, soak it fully and return to your normal cycle.
Afterwards, and what to note
Keep the plant out of full midday sun for the first week or so, in bright shade, and then return it to its usual spot. Expect it to sulk briefly and to drop a few more leaves in the following fortnight; that is handling damage showing up late, not a problem with the repot.
Write down the date you repotted, the pot size and the mix you used, and stand the collected fallen leaves on a dry tray with the same date. Two useful things come out of that record: you learn how many years your mix lasts before it stops draining, and you get a dated batch of leaf propagations that tells you exactly how long rooting takes in your conditions.