String of Pearls: Why Yours Is Shrivelling, Balding or Bursting

Curio rowleyanus, formerly Senecio, is one of the most photographed and most frequently killed houseplants there is. The reason is a mismatch: it is a drought-adapted succulent with an unusually shallow root system, sold in a hanging pot that people water like a normal houseplant.

Water, which is the whole thing

Soak thoroughly, then let the soil dry out completely, then wait a few more days. Roughly every two to three weeks in summer and every four to six in winter.

The pearls are water storage. Read them:

Plump and round. Content.

Slightly shrivelled, a little flat or wrinkled. Thirsty. Water and they refill within a few days. This is a safe state to let it reach.

Mushy, translucent, or bursting and squashy. Overwatered. The pearls have taken up more than the cells can hold. Far harder to reverse than thirst.

Yellowing at the stem where it meets the soil. Rot. Act now.

The pot problem

String of pearls has shallow, fine roots that sit in the top few centimetres. Put it in a deep pot and the bottom two thirds is soil no root ever reaches, which stays wet for weeks and rots the plant from below.

Use a shallow pot, or a wide low bowl, with a drainage hole. Terracotta is ideal because it breathes and dries fast.

This one change prevents most string of pearls deaths, and it is the reason a plant that looked perfect in the shop declines within two months at home in a deep decorative hanging pot.

Light

Bright, including a few hours of direct sun. This is a desert plant from southwest Africa and it wants considerably more light than a typical trailing houseplant.

In low light the strands stretch, the gaps between pearls lengthen, and the plant looks sparse. That stretching does not reverse.

Near a south or east window is right. Introduce strong sun gradually, since a plant that has been indoors will scorch if moved straight into full summer sun.

Why the top of the pot goes bald

Extremely common and it looks like the plant is dying from the crown. It usually is not.

The strands nearest the soil are the oldest. They shade themselves out, get less light than the trailing ends, and gradually die back, leaving a bare crown with long strands hanging from it.

The fix is simple and nobody does it: take the trailing strands and coil them back onto the soil surface, pinning them down with a bent paperclip or a small stone. Wherever a node touches damp soil it roots, and the pot fills back in.

You can also cut strands into sections and lay them on the surface. Same result, and it turns one sparse plant into a full one within a season.

Propagating

The easiest succulent there is to propagate. Lay a length of strand on top of moist mix, so the little nubs where pearls join the stem are in contact with the soil, and press it down gently. Roots form at those points within a couple of weeks.

Do not bury it and do not root it in water, which rots it. Surface contact with slightly moist soil is all it wants.

Soil and feeding

Cactus mix, or ordinary compost cut roughly half and half with grit, pumice or perlite. It should pour rather than clump.

Feed once or twice across spring and summer at half strength. It needs very little and overfeeding produces weak stretched growth.

The pet point, which people get wrong

String of pearls is toxic to cats and dogs, causing vomiting, diarrhoea and skin irritation on contact with the sap.

This matters more than for most toxic houseplants because of where it lives. A trailing plant hanging at cat height, made of small round dangling objects, is close to purpose-built to be batted and chewed. If you have a cat, hang it genuinely out of reach or choose something else.

String of pearls is confused with string of tears, string of bananas and string of beads, all related Curio species with slightly different water needs. Photograph a strand close up so the pearl shape is clear and Identium will tell you which you have.