Botanical name: Codiaeum variegatum
Crotons commonly called Joseph's Coat are popular houseplants on account of their vivid foliage colors and varied leaf shapes. These plants are native to Indonesia, Malaysia, Australia and Western Pacific Ocean islands where they grow in open forests and scrub. These tropical, evergreen shrubs can grow to a height of about 9 ft. They bear large, thick, leathery and shiny leaves. The stiff leaves are borne on an upright stem; the usual pattern is large and lobed foliage on which there are distinctly colored veins. Crotons are not easy to grow under room conditions but if they are cared for appropriately, they make resilient and beautiful houseplants suitable for home decor.
The basic variety is Codiaeum variegatum pictum and over the years different named types have appeared. Most have Laurel-like foliage, but there are also forked leaves, long ribbons, lobed leaves, twisted and curled types. Identification is not easy. Popular varieties of Crotons include Norma with green leaves with red veins and splashes of yellow, Bravo with green leaves splashed with yellow, Reidii with green leaves splashed with red, aucubifolium among many others. The lobed Croton varieties include Craigii and Holuffiana. Other common varieties are Gold finger, Gold star, Gold Moon, Mrs Iceton, Excellent among many others.
Crotons prefer bright light with some direct sunlight, near an east- or a west-facing window. Learn more on how to ensure your plant receives the correct light in this guide on understanding light for houseplants.
Keep soil moist at all times for Joseph's Coat during the growing season but reduce watering in the cold season to maintain the soil slightly moist. Avoid waterlogging as it may lead to the yellowing of leaves. Learn more on how to water houseplants.
Average warmth with a minimum of 150C is ideal for Crotons. Protect them from draughts and don't expose them to low temperatures as the leaves may get brown edges or drop and the plant may die. Find out more on temperature for houseplants.
Crotons requires high humidity. Mist the leaves regularly and clean them by damp-wiping with a soft cloth to get rid of dust. Raise humidity by more frequent misting or set the pot on a wet pebble tray. Crotons can also be grown in a terrarium as a high humidity can be maintained in a terrarium.
Feed Crotons every 2 weeks during the growing period with a balanced water-soluble fertilizer. Withhold feeding in the cold season as growth is minimal and feeding at this time can lead to fertilizer burn. Replenish the top 2-3 inches of soil with fresh soil every few 2-3 years. Find out more on feeding houseplants.
Repot Crotons during the growing period if the plants are overcrowded. Carefully cut through the roots with a knife and pot them separately. Use a pot one-size larger and free-draining soil that is rich in organic matter. Ensure the pot has drainage holes to prevent waterlogging. To control the size of Joseph's Coat keep them in the same pot, so that the roots are confined.
Pruning of Crotons is done by removal of yellow and dead leaves to maintain the plant neat and tidy. The plants can become leggy with age or too large. Cut-back the branches to the desired height to encourage fresh and vigorous growth for a more compact plant. The best time to cut back is at the beginning of the growing season. Do not cut back the plant by more than one third. The foliage emanating from the cutting-back, can be used to propagate new plants. Learn more on how to prune houseplants.
Crotons can be propagated during the growing season from stem cuttings or by air layering.
Propagation of Crotons from Stem cuttings
Take non-woody stem cuttings about 4 in. long, strip off the lower lower leaves leaving 2-3 leaves on top, allow the sap to dry, dip the lower cut end of the cutting in a rooting hormone and stick it in moist rooting soil. To hasten rooting of Crotons, create a mini greenhouse by covering the set up with a polythene bag, ensure the leaves do not touch the bag too much by propping it with sticks. Place the set up in warm, shaded spot, maintain the soil moist through out. New growth indicates the cutting has rooted. Remove the plastic bag when at least 2 new leaves have developed. In 4-6 months, there will be adequate root development and normal plant care can begin.
Propagation of Crotons by Air layering
This consists of notching the stem of a healthy Croton plant, coating the notch with a rooting hormone, surrounding the area with damp moss and then covering it with a polythene film or clear plastic wrap. Maintain the moss moist through out. After the roots have formed sever the stem just below the covered part and carefully pot the rooted cutting in moist soil. Place the set up in a warm shaded place. Maintain the soil moist through out until new growth has been observed and the plant has grown at least 2 sets of new leaves.
Too little light is the reason. Crotons prefer bright light with some direct sunlight, near an east- or a west-facing window. Learn more on how to ensure your plant receives the correct light in this guide on understanding light for houseplants.
There are three causes of loss of lower leaves in Crotons. One is dry air if the leaves have dry tips; raise humidity by more frequent misting or set the pot on a wet pebble tray. Crotons can also be grown in a terrarium as a high humidity can be maintained in a terrarium. Reason number two is that the soil is too dry especially if the leaves have brown tips; maintain the soil moist at all times and never allow the soil-ball to dry out completely. The third reason is the temperature is too low if leaves have brown edges; protect Crotons from cold draughts.
Waterlogging is the cause. Check the condition of the of the soil. If waterlogged, repot Croton in fresh free-draining soil and ensure the pot has drainage holes.
Sudden change of growing conditions is the reason. Gradually acclimatize the plant to new growing conditions; do not move it suddenly to new growing conditions.
Common pests in Crotons are Mealy Bugs and Spider Mites. Isolate the affected plant to prevent spread to other plants. Keep the plant properly pruned at all times to reduce the hiding places for these pests.
As with many plants of the Euphorbiaceae family, Crotons (Codiaeum spp) produce a sap that can cause skin irritation and eczema in sensitive skin. The bark, roots, latex and leaves are poisonous. The sap contains the toxic chemical compound 5-deoxyingenol. Consumption of the plant's seed can be fatal to humans.