Petra Croton (Codiaeum Variegatum)

Petra Croton (Codiaeum Variegatum) may be the most psychedelic-looking tropical plant on Earth. Native to the South Pacific (Indonesia, Malaysia, Australia, the Pacific Islands) and roughly 2’-4’ high and tall, this living kaleidoscope’s foliage is so bright and colorful that it makes ‘70s-style black light posters jealous. Petra Croton is unique, it’s gaudy … and it’s absolutely captivating!

Petra Croton’s new leaves emerge bright green, but with yellow veins and edges, giving each leaf a sort of “neon x-ray” look. For most plants, that would be enough, but for Petra, it’s just the beginning. As the plant ages and its leaves mature, eventually growing up to 3” wide and 11” long, their colors slowly change. Bright green and yellow becomes dark green with orange veins and edges—which, in turn, deepens to burgundy-green with red veins.

Best of all, because Petra Croton is technically an evergreen (ha), most specimens display leaves in every stage of this color progression at the same time. The end result is a fireworks display of orange, yellow, red, purple, and sometimes even green on a single plant. It’s amazing.

Crotons do have a few important care requirements, but they’re reasonable. Petra wants as much light as possible (though constant direct sun can scorch its leaves, so keep an eye on it), and prefers moderate temperatures (above 60°F), high humidity, and room-temperature water in soil that is usually damp, but never soggy. It dislikes drafts, cold, and being moved around (maybe it’s part couch potato?) but requires little fertilizer or pruning. 

Petra Croton. It’s one of our favorites. It’s sure to be one of yours, too. 

Characteristics and traits of a Petra Croton (Codiaeum Variegatum)

Scientific Name: Codiaeum Variegatum (syn. Croton Variegatum, Croton Variegatum var ‘Pictum’)

Genus: Codiaeum

Family: Euphorbiaceae

Common Name: Petra Croton, Garden Croton, Joseph’s Coat, Fire Croton, Variegated Croton

Indoor:   All year in temperatures above 60°F

Outdoor Zones: 10-11 

Type: Perennial evergreen; propagated via stem cuttings and air layering

Mature Height: 3’ - 4’ (up to 10’ outdoors)

Mature Width: 2’ - 3’

Plant Height when Shipped: XXXXXX

Growth Rate: Slow to Medium

Flower: Rare on indoor specimens. Spikes of small, white-yellow flowers that have two forms (male and female) on the same plant. 

Foliage: Thick, glossy oval leaves ranging in color from light green to dark purple-green, variegated with lighter midribs and veins in colors ranging from yellow to red.

Plant Care and Advice for Petra Croton (Codiaeum Variegatum)

Grown In:  Inside: all zones year round, Outside: zones 10-11

Light Requirements: Prefers bright indirect or full sun (though it may require afternoon protection in some locations).

Water Requirements: March-August, give generous drink when top ½” - 1” of soil becomes dry, then let drain. In cooler months, wait for top 2” to dry and give smaller sips.  

Drought Tolerance: Good

Temperature:  Prefers indoor temps of 65°F-85°F. Bring potted plants in when temps fall below 50°F. Can handle wider extremes if planted directly in the ground.    

Air Purification: Good

Toxicity: Toxic. Sap can cause skin irritation, most tissues can cause vomiting, diarrhea, and other symptoms when consumed, and seeds can be fatal to children.

Fertilizer: Slow-release acidic fertilizer 2-3 times March-July, none in winter.

Container Friendly: Yes, but good drainage is crucial.

Planting:

Petra Croton can get stressed out by repotting, so only repot when the plant’s roots begin to peek through the pot’s drainage holes (every 2-3 years in a healthy croton). Choose a pot 1”-2” larger in diameter than the existing pot (terra cotta is best because it “breathes” better).

While it’s important to use rich, quick-draining soil with ample organic matter, you do have some leeway as to its precise formulation. Most quality potting soils with pH between 4.5-6.5 are fine. Some growers use a 2:1 mix of peat and perlite/sane, and others recommend a 6:3:1 mix of peat, pine bark, and sand.  

Plant Care:

The basic rule for lighting with a Petra Croton is that it wants as much light as possible—that’s what makes it so colorful—right up until the point it’s getting too much light. In practice, this means bright indirect light is always great, and in many instances direct or full sun is also great—unless the plant’s leaves begin to fade and/or scorch, in which case the plant may need a bit of protection during the harshest hours. That said, Petra Croton is often grown outdoors in full sun in Florida, there’s a fair chance it can handle whatever light you have available. It can also tolerate medium light / partial shade, though it will lose some of its rainbow color and stay greener. 

Crotons go through a lot of water, but they dislike wet feet. During spring and summer, give it a deep drink, wetting its soil until water begins to flow out the pot’s drainage hole, then let the soil drain completely. When the top dries out to a depth of ½”-1”—which could be as soon as the next day in hot weather—or if the younger leaves start to wilt, give the plant another drink.

Once the weather cools in fall, offer less water and let the soil dry to 2” deep before rewatering—and no matter what time of year it is, use room-temperature water to avoid thermal shock to Petra’s roots.  

The higher the humidity, the happier your Petra Croton will be. Daily misting is strongly advised, as is placing the plant on a tray filled with 1” of pebbles and ¾” of water (so the water doesn’t touch the bottom of the pot). As a tropical native, Petra also prefers temperatures between 65-85°F (18-27°C), and especially dislikes temps cooler than 60°F. When planted directly in the soil outdoors, they can handle a wider range of temperatures, but should still not be considered reliably frost-hardy.

Surprisingly, Petra Croton doesn’t need much fertilizer to maintain its glorious foliage. Some owners feed a general houseplant fertilizer at half strength every two weeks during spring and summer. Others favor a slow-release, acidic fertilizer applied only 2-3 times between early March and late July. Whichever technique best suits your style, don’t fertilize in fall or winter, when the plant is relatively dormant.

Petra Croton looks fantastic in any location, but not all locations are ideal for it. In addition to giving it as much light as possible, avoid placing it near A/C vents, drafty doors or windows, or heat vents, all of which can sap its humidity, expose the plant to cold, or both.

Also, be aware that Petra Croton likes to stay in one place and tends to stress out when it is moved. So if it drops leaves when you first bring it home or when you move it from one room to another, don’t be alarmed. That’s just Petra’s way of getting acclimated. If you give it the right TLC otherwise (and, obviously, minimize additional movement), the plant should fully recover.

Expert Advice:

As mentioned, Codiaeum Variegatum tends to drop a few leaves when it’s relocated. No worries. However, if the plant is dropping an unusual number of its lower leaves, it may be thirsty.

The leaves also provide a myriad of additional clues to help you manage your Codiaeum Variegatum’s health. For instance, if they’re overly green, you’ll want to give the plant more light—conversely, if you notice bleached or grayish patches on the leaves that face the sun, the plant needs less light and/or heat.

If Codiaeum Variegatum’s leaves begin to twist, reduce fertilizer. If their tips or edges become brown or “crispy”, it’s likely a cry for more humidity, less cold, or more water. A quick examination of the plant’s surroundings and your care practices should help you narrow it down. Also, if the leaves develop brown spots with yellow edges, there’s likely excess salt in the soil (probably from fertilizer). Flush the soil with lots of fresh water, making sure it drains fully as well. 

Wilting leaves on Codiaeum Variegatum can actually mean two opposite things. If newer growth wilts, it’s likely a sign that the plant is ready for more water. However, crotons also wilt when they're getting too much water, so you’ll have to use your best judgement on which it is.

Codiaeum Variegatum has above-average pest resistance, and maintaining high humidity around the plant and wiping its leaves clean with a damp cloth on occasion can do wonders to prevent infestations. However, pests such as mealybugs, scale, thrips, and especially spider mites can still appear. Viable treatments include neem oil, insecticidal soap, and dabbing the pests with a cotton swab dipped in rubbing alcohol. 

There are also a couple important bacterial or fungal infections to watch out for on Codiaeum Variegatum. Dark, water-soaked patches on the leaves can be a sign of anthracnose leaf spot, which can be treated with neem oil, a copper spray, or a Bacillus Subtilis spray. Neem oil can also treat powdery mildew, an infection made more likely by wet leaves (so don’t be too heavy-handed with your misting).

Pruning is rarely needed with Codiaeum Variegatum, but if you do wish to shape the plant or remove unhealthy foliage, be aware that the plant’s sap can cause skin irritation. 

The sap is also a concern when propagating Codiaeum Variegatum, as Stem cuttings are the preferred method. Simply cut off a 3”-4” length of stem and strip off all but the uppermost 3-5 leaves. Insert the stem in rooting hormone (optional, but helpful) and place it in a small pot. Keep the soil moist, humidity high (place a plastic bag loosely over it if need be), and temps in the 70°F-80°F range, and the cutting should root within a month. Some plant keepers also report success rooting this plant in plain water, but we prefer the soil method.

A slightly more complex method of propagation is air layering. On an existing Codiaeum Variegatum plant, find a branch you want to be a new plant and make a diagonal cut roughly ⅓ of the way through it where you want the roots to form. Sprinkle rooting hormone in the cut, then slide a toothpick, the tine of a plastic fork, or some other small obstruction into the cut to keep it open. Then, wrap the wound in a clump of damp sphagnum moss and wrap it with plastic wrap to hold it in place and retain the moisture. When you see roots winding through the moss (it should take several weeks), unwrap the “bandage”, cut the stem the rest of the way through, and plant your new croton in its own pot.

Richard, the zones on this one are unclear. Some sources say 9b-11, others say 11-12, Floridata says 10-11, which seemed safest to me. Your call.