Sedum Succulent

The succulent that tells you how much sun it is getting

Sedum rubrotinctum — jelly bean plant, or just Sedum in most local nurseries — grows as short upright stems crowded with plump, glossy, bean-shaped leaves. In moderate light they stay flat green. Push the light up and the tips flush red, then the colour spreads down the leaf. That colour is a light meter: green means the plant is coasting, red means it is working.

It stays small and branches slowly into a low cluster, so it belongs on a windowsill or a desk rather than in a corner that needs filling.

Light

Bright light, with a few hours of direct morning sun if you can give it. An east-facing sill is close to ideal. It survives in bright indirect light but it stretches — the gaps between leaves open up, the stems lean toward the window, and the red never arrives. What it will not take is full afternoon sun through glass in June, which scorches the leaf faces brown. Pull it back a foot once the afternoons are past 38°C. The summer care guide covers the same adjustment for the rest of the collection.

Water

Every two to three weeks, and only once the soil is dry all the way through. The plant carries its own reserve in those leaves, so a missed watering costs it nothing and two waterings too close together cost it a great deal. Through the July and August monsoon, when nothing indoors dries properly, stretch the gap out and check the soil with a finger instead of the calendar.

The warning sign is leaves dropping at the lightest touch while still firm and full. That is stem rot, not thirst. Stop watering completely and read how to save a dying succulent.

Soil and potting

A gritty, fast-draining mix in a pot with a drainage hole — the soil mix guide has the ratio. Ordinary garden soil holds far too much water around a shallow root system.

Multiplying it

This is one of the easiest plants in the shop to propagate. A leaf knocked off in passing will root on the surface of dry soil with no help at all, which is why established plants are usually surrounded by volunteers.

Good to know

The sap can irritate skin, and the leaves are mildly toxic if a pet or a small child chews them. Keep it off a low shelf and wash your hands after taking cuttings.