Cyanastrum cordifolium

An evergreen-forest geophyte from tropical Africa

Cyanastrum cordifolium is a small corm-forming perennial native from southern Nigeria through Cameroon, Equatorial Guinea and Gabon to the Congo basin. It grows on the floor of primary evergreen rainforest from lowland sites to about 1,000 m.

Each active corm usually bears one heart-shaped basal leaf, while new corms form above older ones and create a short chain. Several active corms can therefore place more than one leaf above ground.

The inflorescence arises from a separate corm scale and need not appear at the same time as a new leaf. In warm, moist cultivation the foliage may remain evergreen throughout the year.

Care through active growth and seasonal rest

Leaf, flower and corm care

The plant normally supports its own leaves and needs no stake unless a damaged or unusually long leaf stalk is at risk of breaking. Let green leaves remain until they yellow naturally, then cut them at the base without pulling on the corm chain.

Watering active corms

Keep the root zone lightly and evenly moist. Constant saturation can rot the corm chain and thick fibrous roots.

Warmth while the corm chain is active

Warm, stable conditions suit this tropical African species. Keep Cyanastrum cordifolium in stable indoor warmth and protect the root zone from cold surfaces.

Humidity and airflow

Average to moderately humid room air is suitable when the roots remain evenly moist. Higher humidity can help new leaves expand cleanly, but still air around a wet corm chain encourages decay.

Nutrition for new leaves and corms

New leaves and corms can be fed with a balanced complete fertiliser at a low dose. Feed again only while leaves and corms are actively developing, following the product label for strength.

Repotting the corm chain

Repot when roots fill the container, connected corms press against the rim or the mix no longer wets and drains evenly. Choose a pot only slightly wider and keep sound roots attached to each corm section.

Problems to check on Cyanastrum cordifolium

Heart-shaped leaves droop or develop crisp edges

A dry root zone, direct sun or excessive heat can make the thin forest-floor leaves lose firmness. Check below the surface and rewet evenly if the mix is drying. If the pot is already wet, inspect the thick roots and connected corms before watering again; failed roots produce the same wilted appearance.

Rounded corms form a visible chain

New corms naturally develop above older ones, producing a connected chain. Firm green or brownish corm tissue with healthy roots is normal. Add a small amount of mix only where roots are exposed, without burying the newest bud. A soft, dark or foul-smelling corm strongly suggests decay. Separate it promptly from the firm, healthy parts of the corm chain.

New leaves become progressively smaller or paler

This shade-adapted plant does not automatically need stronger light. First check if the roots are crowded, the corms are soft or the mix has become compacted. If roots and corms are sound, provide a modest complete feed and ensure the plant receives steady filtered daylight. Move it gradually and keep it out of direct sun.

Several leaves yellow at the same time

One ageing leaf can yellow while the corm chain continues producing new growth. Multiple yellow leaves above saturated mix point to poor root aeration or corm rot. Unpot the plant, remove collapsing roots and retain only firm connected corms. Avoid interpreting widespread yellowing as a required dry dormancy.

Fine pale speckles or sticky deposits appear

Sucking pests can settle on the undersides of the glossy leaves and along the stalks. Isolate the plant and inspect with a lens for mites, scale or mealybugs before choosing a treatment. Clean the leaf surfaces gently and repeat inspections on emerging growth, where small colonies are easiest to miss.

Keep Cyanastrum cordifolium away from children and pets

• Keep this plant away from children, cats and dogs.
• Its effects after chewing or swallowing are unclear, and plant material can still cause an upset stomach.
• Contact a veterinarian or medical professional if symptoms develop or do not settle.

About the name Cyanastrum cordifolium

Cyanastrum combines Greek elements meaning dark blue and star, a reference to the blue, star-shaped flowers of this tropical African genus. Cordifolium means heart-leaved, from the Latin cor, heart, and folium, leaf.

Daniel Oliver established the genus Cyanastrum in 1891 in Hooker’s Icones Plantarum, volume 20, plate 1965.

Daniel Oliver first described Cyanastrum cordifolium in 1891 in Hooker’s Icones Plantarum, volume 20, plate 1965.