Description
Special Features of Codiaeum (Croton)
Codiaeum is a genus of perennial evergreen trees, shrubs, and herbaceous plants of the family Euphorbiaceae containing about a dozen species (14 to 17). Codiaeums are found across eastern India, Malaysia, on some islands of the Malay Archipelago (Greater Sunda, Lesser Sunda, and Moluccas) where they had been cultivated as popular ornamental plants long before the 1860s when the first species were brought to Europe.
Only Codiaeum variegatum is cultivated indoors. It is a shrub with yellow veins that grows to 50 up to 300 centimeters tall. For a century and a half, it has been extensively hybridized and became a source of so many varieties and hybrids that it is almost impossible to clearly classify them now: Excellent, Gold Finger, Gold King, Gold Star, Gold Sun, Norma, and Vulcan. By the way, Norma has red veins on green leaves spotted with yellow; Vulcan has yellow leaves with green veins and red margins.
The leaf shapes are varied, often asymmetrical. The leaves may be narrow or wide, flat or twisted into a kind of spiral, belt-like or finger-like, and they may have strait or undulate edges. The most decorative are young plants (younger than 3 years old). Their colouring is dominated by yellows, greens, and bright light greens. When the plants age, the yellow colouring tends to increase; then purple, red, and pink spots and stripes appear. It is also easy to notice white, orange, and brown colours, sometimes traces of black.
The beginners need to know the following:
1) Codiaeum is often called Joseph's coat or Croton. In fact, Croton belongs to a different genus of the same family that is much more numerous (approximately 1,200 species) and widespread.
2) Codiaeum blooms regularly in response to the proper care, including timely feeding, but blooming requires a lot of energy and white or yellow flowers developing in the early spring are small and inconspicuous. It is better to remove them immediately.
3) Codiaeum usually grows quickly (one might say very quickly) but sometimes irregularly. It can develop 2 to 4 leaves and stop growing for some time.
4) Codiaeum needs stagnant warm and wet atmosphere and therefore is not suitable for gardens, balconies, or porches in the summer.
5) Codiaeum makes people calm, helps to relieve nervous tension, gives confidence, and helps to make a choice. It is even said to protect teenagers from getting into bad company.
IMPORTANT!
6) Codiaeum's milky sap that bleeds from a damaged leaf or stem may cause skin irritation and is considered poisonous! After handling the plant, wash your hands with soap and water!
The Secrets to Successfully Growing Codiaeum (Croton)
In low light, variegated foliage loses colour and the leaves turn boring solid green. In addition, in partial shade, the leaves tend to grow smaller and slower. Select a very bright place protected from direct midday sunlight. In the winter, choose a southern or western exposure window, unless you use supplemental artificial lighting. In summer, the east- or west-facing window is best. Make sure the crown is uniform by turning the plant to the light source.
In the spring and summer, water your Codiaeum regularly and plentifully, as underwatering can cause the leaves droop. Do not let the soil dry out deeper than 1-2 centimeters and do not let the pot stand in water either. In the autumn and winter, reduce watering. Use soft and lukewarm (room temperature) water. Cold water can cause the plant to drop leaves.
Codiaeum is very sensitive to air humidity. It loves being sprayed daily, wiped weekly (in any season) with a damp cloth, and placed on a tray of wet pebbles or expanded clay. Additionally, you can place a wide bowl with water close to the pot. Adding Zircon to water for irrigation and misting (1-2 drops per cup) will stimulate the growth of new leaves. Fancy trying?
The best temperatures are 20-22 ° C in the summer and 18-20 ° C in the winter (October to February). The plant does not like abrupt fluctuations in temperatures and drafts, which can cause leaves crack and / or drop. The roots can not withstand the cold. In the winter, the pot placed in a cold window or on the floor should be protected from the bottom with a pad (a thick wooden plank or a piece of foam board).
From March to September when the plant grows, fertilize it weekly with any compound mineral fertilizer for foliage plants. Read the instructions carefully to check on how much nitrogen the fertilizer contains. It is even better to use a specific fertilizer for variegated plants. With the onset of cold weather, feed once per month. Feed the plant immediately after watering rather than before watering.
Repot young plants every year and older plants every 2 or better 3 years. A new ceramic or plastic pot should only be 2-3 centimeters larger because Codiaeum dislikes large pots. Fill the pot with drainage material (a mixture of potsherds, charcoal, and expanded clay) to a quarter of the pot height to ensure good drainage and avoid the tragic consequence of wet feet, root rot. Take care not to harm roots during repotting. Fresh soil should be weak acidic (pH = 5.0-6.0) or neutral (pH = 6.0-7.0). For a young plant, use a mixture of loam, leaf mold, and sand at 1:2:1; for mature plants slightly increase the share of loam. You might want to experiment with adding small amounts of peat soil or bone meal.
Codiaeum is usually propagated by 10-15 centimetres long tip cuttings. In the spring (late May or early June) cut a lignified cutting with a sharp knife, clean from sap with warm water, tie the leaves loosely around the trunk, and plant in a mixture of peat moss, peat, and sand. Cover with transparent plastic foil. Air daily and spray the cutting. If you have done everything correctly, it will take root no later than in a month. To accelerate rooting, you can a) dip the cutting before planting in growth biostimulant (Kornevin, for example); b) warm the propagating case.
Codiaeum can be also propagated by air layering. Selecta a flexible branch, bare a portion of the stem, bend it and put the soil on top, sprinkle and secure. When the branch takes root, cut it and move into a new pot.
The third propagation method is by seed in January and February. Soak the seeds in Kornevin for a few hours and plant in a propagating case. Seedlings will appear in 3-4 weeks.
Prune shoots and branches to form a shrub in the early spring.
Potential Problems
If leaf colouring in young plants is less bright than in old ones, do not worries as this is okay.
The diversity of colour may be lost in excess light (purely physical phenomenon of burning), poor light or insufficient amount of elements in fertilizer.
Dry brown spots on the leaves indicate sunburn.
If the leaf tips become brown and dry, the cause can be underwatering, low air humidity, or low temperatures. Moreover, underwatering and too dry an atmosphere can cause bottom leaves drop, and too low temperatures can cause root rot because evaporation from the soil is slow (i.e. the situation is equivalent to overwatering). Low temperatures have other undesirable consequences. The foliage changes colour, edges turn brown, and the growth slows.
Lower leaves may also drop with age.
If the leaves turn yellow and dry, mist more frequently, several times a day (this is especially true in the winter when all heating devices are on). However, remember to check first to make sure the soil is not soggy or clumped and the plant is not potbound.
The leaves can crack because of irregular watering, dry air, sudden fluctuations in temperatures, or nitrogen overfeeding.
Purple growth on the undersides of the leaves that reappears after washing and leaf drop most likely indicate a fungal disease. Apply fungicides to the plants and the soil 3-4 times at 10-day intervals.
Codiaeum can often get the following pests:
- Fungus gnats (small flying midges). Their larvae are more dangerous for the root system than the gnats themselves. Apply insecticide to the plant and soil.
- Red spider mites. Indirect signs: fine webbings on the undersides of the leaves, discolouration (the leaves turn dull).
- Mealy bugs (white beetles with an oval body and numerous legs).
- Scale insects. Sign: black and brown waxy plaque on different parts of a plant.
As you can see, the plant requires lots of care and attention but it will fill your everyday life with bright colours and make you feel good.
