Gadenin日本語Get the appThe shape of the year
A lithops runs one cycle a year and each phase locks out certain jobs. Growth happens in the cooler half of the year, flowering comes in autumn, the new leaf pair is built over winter out of the old pair, and summer is a rest. The single organizing principle is that the plant is either drawing water from the pot or drawing it from its own leaves, and it never does both.
Use the descriptions rather than the months. Depending on your climate and hemisphere the phases can shift by six weeks or more, and a plant under lights indoors will not match a plant on an unheated porch in the same city.
| Phase | Trigger you can see | Main jobs |
|---|---|---|
| Waking, late summer | Cooler nights, bodies firming after the summer flat | First soak, start feeding lightly, repot if needed |
| Flowering, autumn | Bud pushing out of the slit, opening in the afternoon | Water on a dry pot, pollinate if you want seed, maximum sun |
| Leaf change, late autumn to spring | New pair visible in the slit, old pair beginning to soften | No water at all, no repotting, keep light high |
| Rest, summer | Old leaves long gone, growth stopped, colors dull | No water or nearly none, shade from extreme heat, keep airy |
Late summer into autumn: the growing season
The year effectively begins when the heat breaks. Bodies that spent summer flat and dull start to look firmer, and that is your cue to give the first thorough soak since spring. From that point the plant is actively growing and you water whenever the pot has gone completely dry, which in a gritty mix in good sun means roughly every two to three weeks.
This is also when flowering happens. A bud emerges from the slit and opens on sunny afternoons over several days, closing each evening. Flowering takes energy but needs no intervention beyond the normal watering; the one thing to add is sun, since flowers open poorly in weak light. If you want seed, this is your only chance in the year and you need two unrelated plants in flower together.
If a repot is due, do it early in this phase rather than late, so that the plant has weeks of active growth to rebuild roots before the leaf change begins. Feeding, if you feed at all, belongs here too: a low-nitrogen fertilizer at quarter strength, once or at most twice across the whole growing season. Lithops in a mineral mix need very little and overfed plants grow soft and split easily.
The leaf change: months of doing nothing
Once flowering finishes, look into the slit. When you can see a fresh pair of leaves beginning to form in there, the growing season is over and the watering can goes away. From this moment until the old leaves are dry paper, the plant gets no water, and depending on your conditions that is anywhere from two to five months.
During this period the plant looks progressively worse and it is supposed to. The old leaves lose their color, soften, wrinkle and finally collapse into thin translucent shells that sit like a paper cup around the new bodies. The new pair rises through them, tight and freshly marked. Leave the old shells in place. They are still being drained, and pulling them off early both wastes reserves and tears the new tissue underneath.
The only two jobs in this phase are light and air. Give the plant everything the season offers, supplement with a grow light if the winter sun is weak where you are, and keep air moving so no dampness lingers. Do not repot, do not divide, do not fertilize, and above all do not water because the plant looks shriveled. It looks shriveled because it is doing exactly what it evolved to do.
If two plants in the same tray change leaves a month apart, that is normal and each one is watered on its own schedule, not the tray's. Once you have more than a few plants, group them by phase rather than by pot size so that a watering never reaches a plant that is mid-change.
Spring and summer: the first drink, then the long rest
When the old leaves have gone completely to paper and crumble at a touch, the leaf change is over and you can water again. Give one good soak and the new bodies will plump and gloss within a fortnight, which is the most satisfying moment of the lithops year. Continue watering on a bone-dry pot through the rest of spring, but start tapering as the weather warms.
Once daytime temperatures are regularly above about 85F to 90F (29C to 32C), the plant stops growing and enters its summer rest. Water is neither needed nor safe: warm damp mix and inactive roots is the classic summer rot. Withhold entirely, or if the bodies visibly shrink over several weeks, give a small amount of water in the early morning once a month and no more. Shade the pot from the hottest afternoon sun, keep air moving, and otherwise leave the plant alone until the nights cool and the cycle starts again.
The old shells are worth clearing away at the end of the leaf change, but only once they lift free with no resistance at all. If a shell is still attached, leave it another few weeks. There is no benefit to a tidy plant and a real cost to a torn one.
A year of notes worth keeping
Lithops reward record-keeping more than almost any other plant because the whole cycle turns on dates you cannot otherwise remember. Note six things across the year: the first soak of late summer, the date the first flower opened, the date you saw the new pair and stopped watering, the date the old leaves were finally paper, the date of the first spring drink, and the date you stopped for summer.
Add the position of each pot and anything that went wrong, with the phase it happened in. By the second year those dates give you a working calendar for your own conditions, which is far more use than any general guide, and by the third year you will be anticipating the switch-off point a week before it arrives rather than discovering it after a watering you should not have given.