The trick to growing crotons (Codiaeum variegatum) is to understand that they are tropical in nature. These multicolored plants with their variegated foliage make popular indoor plants, but they sometimes have a reputation for being fussy. Still, the basic care of houseplants like crotons is much easier once you understand where they come from and what they need to thrive.
I. Appearance and Characteristics
Codiaeum variegatum (fire croton, garden croton, or variegated croton; syn. Croton variegatum L.) is a species of plant in the genus Codiaeum, which is a member of the family Euphorbiaceae. It was described by Carl Linnaeus in 1753. It is native to Indonesia, Malaysia, Australia, and the western Pacific Ocean islands, growing in open forests and scrub.
The garden crotons should not be confused with Croton, a cosmopolitan genus also in the Euphorbiaceae, containing more than 700 species of herbs, shrubs and trees.
It is a tropical, evergreen, monoecious shrub growing to 3 m (9.8 ft) tall and has large, thick, leathery, shiny evergreen leaves, alternately arranged, 5–30 cm (2.0–11.8 in) long and 0.5–8 cm (0.20–3.15 in) broad. The leaf blades can, for example, be ruler-lanceolate, oblong, elliptic, lanceolate, ovate inverted, ovate spatulate, or violin-shaped and coloured green, yellow, or purple in various patterns, depending on the variety. The petiole has a length of 0.2 to 2.5 cm.
The inflorescences are long racemes, 8–30 cm (3.1–11.8 in) long, with male and female flowers on separate inflorescences; the male flowers are white with five small petals and 20–30 stamens, pollens are oval approximately 52×32 microns in size. The female flowers are yellowish, with no petals. The flowering period is usually in early autumn. The fruit is a capsule 9 mm (0.35 in) in diameter, containing three seeds that are 6 mm (0.24 in) in diameter. When cut, stems bleed a milky sap like many of the Euphorbiaceae.
In tropical climates, crotons make attractive hedges and potted patio specimens, valued for their striking foliage. They only survive outdoors where temperatures do not normally drop below 10 to 13 °C (50 to 55 °F) in winter; colder temperatures can cause leaf loss. In colder climates, the plants are grown in greenhouses or as house plants. The cultivated garden crotons are usually smaller than the wild plant, rarely over 1.8 m (5.9 ft) tall, and come in a wide diversity of leaf shapes and colors. They are sometimes grouped under the name Codiaeum variegatum var. pictum (Lodd.) Müll. Arg., though this is not botanically distinct from the species and usually treated as a synonym of it.
As with many of the Euphorbiaceae, the sap can cause contact dermatitis in some people. The bark, roots, latex, and leaves are poisonous. The toxin is the chemical compound 5-deoxy ingenol. The plant contains an oil which is violently purgative and is suspected of being a carcinogen. Consumption of the seeds can be fatal to children.
II. How to Grow and Care
Sunlight
Croton plants need a fair amount of sun. Bright, indirect light is best. Some croton plant varieties don’t tolerate unfiltered, direct sun as well as others, but they will thrive in dappled sunlight. If the plant is getting insufficient sun, the leaves will turn green.
Temperature and Humidity
For croton plants indoors, keep the room above 60 degrees Fahrenheit, and do not expose the plant to cold drafts. Humidity, along with a lack of bright light, can affect leaf color. Keep the humidity level at 40 to 80 percent. If the humidity isn’t high enough, the plant might drop some of its leaves. If you have trouble maintaining the moisture in your home at this level, run a humidifier in the room or set a humidity tray beneath the plant and group it with other plants.
Watering
Keep croton plants evenly moist in the summer. Crotons need about 1 inch of water per week. Reduce watering in the winter to biweekly. Watch the plant for signs that it needs more water, such as wilting young foliage. Increase watering if the wilting noticeably happens during hot weather, but check the top couple of inches of soil with a finger for moisture before you increase water. If it’s still moist, hold off on watering. Mist frequently during the growth period.
Soil
Croton plants prefer well-draining soil with lots of organic material. Most good potting soils are fine, and an ideal range for the soil pH level is between 4.5-6.5 pH. High-pH rock soils are not advisable, as are soils that are very calcium-rich. Most likely, the potting soil found at your nearby big box store is sufficient.
Fertilizing
A popular fertilizer type for croton plant care is an 8-2-10 mix, as they like a lot of potassium. Most often, they’re fed once during the growing season in the early spring (Feb-March), and then again in the late spring (May), giving them a good slow-release acidic fertilizer that will feed them throughout the early summer months. Younger croton plants may require a third feeding somewhere in mid-July. Don’t fertilize outside the growing season in the fall, as the leaves need to mature and harden off before winter.
Planting Instructions
Croton plants outdoors should be planted in loose, well-draining soil. If your area experiences nighttime temperatures of below 50 degrees Fahrenheit at any time of year, you’ll have to pot your croton to bring indoors. Use a sturdy pot that will be able to anchor the plant as it gains height. Croton plants indoors typically should be placed by your brightest window. A quality potting mix that drains efficiently should suffice. Make sure they’re protected from drafts around windows and doors, as well as air-conditioning vents.
Pruning
These plants respond well to trimming, so if your croton plant becomes leggy, prune it back hard at the beginning of the growing season. Remove unhealthy leaves and branches or if you want to maintain a specific shape. Trim just above a node or leaf set. Try not to remove more than 1/3 of the stem at one time. The plant will regrow from the cut portion. If pruning an indoor plant, move it outside once it’s been hardened off (gradually introduced to outdoor conditions for a week).
Propagation
There are several ways to propagate croton plants.
Crotons are most commonly propagated via stem cuttings from a parent plant. Trim a segment from your croton plant that has at least three sets of leaves using a sharp, clean pair of shears. Strip off all but 3-5 leaves from the top of the stem. Place this directly into a glass of water, or dip it into a rooting hormone and place it into a mix of vermiculite, river sand, and peat moss.
Place a cover over the croton plant to help keep it humid as it develops roots. If you don’t have a glass cloche or other humidity-trapping cover, use a plastic bag to simulate one. Once new growth roots have formed, transplant your croton plant gently into a good, well-draining potting mix.
Some people have found it possible to separate croton plants at the root, especially if they have outgrown their container and you see roots growing through the drainage hole. However, this can be problematic, as the croton plant doesn’t like being moved around much, and both your original plant and new stem cuttings may suffer wilting and leaf loss this way.
Finally, there’s a process called air layering. Make a diagonal cut through one-third to half of the diameter of a croton plant stem while it’s still attached to the main plant. Treat the resulting wound with some rooting hormone, and keep it open with a wooden matchstick or toothpick.
Carefully pack damp sphagnum moss around the area, and wrap it in plastic wrap. Make sure it’s kept moist – if the moss begins to turn tan in color, it must be remoistened. The wound will form new growth roots in time. Once those roots have developed, unwrap the plastic wrap, trim the rest of the way through the stem, and repot your new plant in a well-draining potting mix.
Repotting
As your croton plant grows, it will eventually get to the point where it needs a larger pot. Repotting is an important part of croton plant care. Select a pot that’s only 1-2 inches larger in diameter than its current one, and take some of your potting mix and place some in the bottom of the new pot. Then, carefully and gently remove your croton plant from its old pot.
If it appears to be a bit root-bound, separate the roots slightly with your fingers. If they’re too interlocked, use a potting knife to score the roots lightly. Then place the croton plant into the pot, making sure there’s enough potting soil below to put it within an inch of the pot’s top. Carefully fill around the sides of the plant with additional potting soil as needed, and then water it thoroughly to moisten all of the soil and help it settle, stopping when water comes out the bottom of the pot.
Overwintering
Crotons are sensitive to cold weather. If you live in a location that sometimes gets freezing temperatures or infrequent cold snaps, you should consider maintaining your plants in pots and bringing them indoors during temps that plunge lower than 50 degrees Fahrenheit.
To protect in-ground specimens during unexpected cold weather, add about two inches of mulch around the base of the plant to insulate the roots. Use gardener’s blankets to keep the frost away. Use stakes to keep the blankets from weighing down the leaves and branches. These coverings keep in the warmth and protect against ice and harsh winds. Ensure the coverings are staked well or weighted down, so they do not blow away with the wind.
Pests and Diseases
Common Pests & Plant Diseases
Croton is susceptible to a few plant diseases and pests. Crown gall is a common bacterial infection that affects croton. Crown gall appears like thick, swollen growths on the croton’s stems and the veins of its leaves. If your plant gets this disease, it’s recommended that you pull up the plant, discard it, and sterilize the container and gardening tools. It can spread to other plants and leave a path of destruction in its wake.
Anthracnose is a fungal infection that is sometimes called leaf spot or leaf blight. It makes tan-colored spots on the leaves. Cut off any infected foliage, and avoid letting the leaves touch other plants since its spores can spread. If most of the plant looks affected, treat the plant with a standard copper-based garden fungicide.
The insects that like croton include mealybugs, spider mites, scales, and thrips. Use pesticides to remove these pests or less harsh alternatives, such as horticultural oil or insecticidal soap. If left untreated, leaf growth might get stunted, leaves will drop, and the plant can eventually die.
Common Problems
Crotons are finicky plants. Cool breezes, insufficient humidity, and poor soil or insufficient nutrients will affect the health of this plant and can invite a host of problems, including pests, diseases, and a lackluster appearance. Control its environment as best as you can to keep your plant thriving.
Dull Leaf Coloration
The plant’s most vibrant colors come with bright light, but the temperatures must not be sweltering. Summer in tropic zones might be a little too much for some croton. Reduce or hold off on applying fertilizer during a heatwave or higher temps. Intensely hot days will stress out croton and can cause graying or flat colors. Fans or air ventilation can cool down the leaves and will help preserve the health of the leaves. Check water levels, and don’t let the plant dry out during periods of high heat.
Curling or Rolling Leaves
Leaves can roll or twist when they get large. To fix this, reduce fertilizer. The plant is likely growing too quickly and might need more light to grow properly. Move the plant to a location with more lighting if you can.
Leaf Drop
Crotons will drop their leaves at any hint of cool temperatures or cool drafts. Bring in the plant if your plant is in a pot outdoors and the forecast calls for temperatures dipping below 50 degrees Fahrenheit. Insect activity can also cause leaves to fall, namely mites and mealybugs. Inspect the undersides of leaves closely for tiny eggs or insects. You’ll need to clean off the leaves with insecticidal soap or treat the affected areas with horticultural oil to remove the pests.
How to Get to Bloom
All crotons are capable of making tiny star-shaped flowers on long thin stems when grown outdoors. However, croton plants rarely flower when grown indoors. The flower stem looks like a feathery vine, and the tiny blooms don’t have a scent. They can flower any time of year, but it will likely happen when conditions are ideal, such as bright sun, enriched and acidic soil, moist but not soggy soil, and temps in the 70 to 80 degree Fahrenheit range. Also, relocating an indoor plant outdoors when the temperatures are warm might spur flower production.
III. Types of Croton Plants
There are hundreds of varieties of crotons. Today we’ll highlight a few of my favorites. If none appeal to you, don’t stop looking. There’s many croton varieties out there with colorful foliage. There are tons of leaf shapes too!
- C. variegatum ‘Gold Dust’: This particular croton has vibrantly green leaves that look like someone splashed golden-yellow paint all over them. In frost-free areas, it’s common as a landscaping shrub, but it can also be grown indoors. Its leaves are rounded ovals with almost a waxed surface shine. There is another similar cultivar called Gold Star. The only difference between the two is Gold Star has narrower leaves.
- C. variegatum ‘Mammy’: The Mammy varietal is stunning, as its twisted, multi-hued leaves look like long streamers erupting out of its container. Grown indoors, its leaves are more subtle in coloration, tending towards greens and purples with bits of red. Still, if grown in bright light environments, it rapidly becomes an explosion of brilliant color.
- C. variegatum ‘Petra’: One of the most common croton varieties available, Petra’s leaves are green with bold yellow, red, or orange veining and edging. It gives the pointed-oval leaves a lacy appearance when viewed from a slight distance.
- C. variegatum ‘Mother and Daughter’: This unique croton plant has interesting dual narrow leaves. Long and slender, they come to a rounded tip from which the central leaf vein extends, with a secondary leaf attached to it. They grow in variegated shades of green to purple and are really interesting plants to keep!
- C. variegatum ‘Red Iceton’: Red Iceton is one of the more striking croton varieties. Its pointed-tipped oval leaves go through a color change – when new, the leaf color is a bright, warm yellow. As the leaves age, they shade into red and pink hues.
- C. variegatum ‘Magnificent’: The Magnificent croton is similar to the Gold Dust croton in leaf shape and dappled patterning, but that’s where the similarities end. This variety has brilliant shades of red, orange, pink and yellow spattered across the leaves. Occasionally there will be bits of bronze or a purplish hue as well. It’s magnificent, just as its name implies.
- C. variegatum ‘Oakleaf’: This interesting croton variety gets its name from the shape of its leaves, which resemble the multi-fingered oak leaf shape. It tends to have green leaves to bronzes with red, orange, and yellow veining.
- C. variegatum ‘Eleanor Roosevelt’: A stunning change from other plants that are croton varieties, the Eleanor Roosevelt has long, slender leaves. The base hue of the leaves is a nice medium green, but they shift to a deep purple, and all of the leaves are dotted with a bright yellow spotted pattern. This unique variation provides a shift from the broader leaves of other plants.
- C. variegatum ‘Zanzibar’: For those who like ornamental grass, there’s a croton plant for you! The Zanzibar croton plant has such slender leaves that they resemble blades of grass and are dolloped in shades of purple, orange, gold, and even red. These croton plants make a beautiful contrast to their broad-leaved siblings and still share the bright colorways of their species.
IV. Uses and Benefits
Crotons are primarily used for ornamental purposes, brightening up indoor and outdoor spaces with their colorful leaves. In tropical climates, crotons serve as stunning hedges and potted patio highlights, prized for their vibrant foliage. In cooler climates, it makes a terrific houseplant.
