Pleiospilos nelii

Growing in Pots, Balconies & Indoors

Pleiospilos nelii (split rock) is a small, drought-loving mesemb succulent, about 3-7 cm (1-3 in) across, that does very well in a shallow gritty pot. The grower grows it indoors successfully, with the caveat that it needs strong light and careful, minimal watering.

Quick Details

• Container Size: A pot only 15-30% larger than the root ball; move up a size once the plant fills it
• Indoor Suitability: Yes on a bright windowsill – and water even less indoors
• Best Spot: The sunniest windowsill or a bright, airy position
• Soil & Drainage: Very gritty and free-draining – sandy soil gives the best long-term results
• Watering in Pots: Minimal; let it dry fully, and the plant actually likes drought

Indoors & On the Windowsill

• Windowsill houseplant: The grower confirms it grows indoors, but warns to water less there, because fewer factors dry the soil inside. Where a fan, air-conditioner or heater is running, be aware they dry the air, so keep an eye on the plant.
• Light is essential: Give it the brightest sill you have; away from strong light it stretches and weakens.

On a Balcony or Patio

• Light & shelter: Ideal for a hot, sunny, rain-sheltered spot; protect from frost and prolonged wet. Sharp drainage is non-negotiable.
• Practicalities: A small terracotta pot breathes and dries quickly, which suits its dislike of standing moisture.

Choosing the Pot, Soil & Long-Term Care

• Pot & drainage: A snug pot with strong drainage and no standing saucer of water.
• Potting mix: A well-draining mineral mix; the grower prefers sandy soil for the best result (adding a little fertilizer, since sand is lean), and notes lava grit works well for a few years before it needs switching, as potting mix also loses its water absorption over time.
• Feeding: Very little – a small amount of fertilizer, especially in a lean sandy mix.
• Repotting: Move to a pot 15-30% larger than the root ball, switching up only once the plant fills the current one.

Grower’s Container Tip

• Grower’s soil and sizing method: Sandy soil gives the best long-term result but needs a little added fertilizer; lava grit is good but should be switched after a few years, and ordinary potting mix gradually loses its ability to absorb water. Choose a container just 15-30% bigger than the root ball, and only pot up to a larger one once the plant has filled it.

Bloom & Flower Guide

Quick Details

• Bloom Season: Summer into autumn
• Flower Appearance: Daisy-like, many-petalled flowers in yellow, white, red, pink, orange or purple – one flower emerging from between each pair of leaves
• Edibility: Ornamental only

Detailed Blooming Overview

Split rock is a mimicry succulent that looks like a cleft pebble for most of the year, then surprises you with a relatively large, many-rayed daisy-like flower that pushes up from the fissure between the leaves. The blooms are often faintly coconut-scented and open in the afternoon sun.

Flower Characteristics

• Many fine, needle-like petals in a wide range of colours.
• One flower rises from between each leaf pair, large relative to the plant.

Bloom Care & Thinning

• Managing the bloom: Flowers come on mature plants after the growing season – keep it lean and dry and it will bloom on its own.