Crotons (Codiaeum variegatum) are vibrant tropical shrubs renowned for their stunningly colorful and leathery foliage. From a botanical perspective, our survival and growth are entirely dependent on consistently warm temperatures, high humidity, and ample sunlight. Our native Southeast Asian and Pacific Island origins mean we are not genetically equipped to handle cold conditions.
We thrive in environments that mimic our tropical homeland. For us to flourish outdoors, the climate must provide sustained warmth year-round. We require temperatures that remain well above freezing, as our cellular structure is highly susceptible to cold damage. Even a brief exposure to temperatures below 50°F (10°C) can cause us significant stress, leading to leaf drop and stunted growth. A hard freeze is almost always fatal. Furthermore, we crave high atmospheric humidity to keep our large leaves turgid and prevent them from drying out or becoming crispy at the edges.
Based on these physiological needs, the United States Department of Agriculture (USDA) hardiness zones where we can be successfully grown as permanent outdoor landscape plants are USDA Zones 10 through 12. In these zones, the average annual extreme minimum temperature ranges from 30°F to 50°F (-1.1°C to 10°C). This means the risk of frost or freezing temperatures is minimal to non-existent.
In USDA Zone 9b, where minimum temperatures can dip to 25°F (-3.9°C), our existence outdoors is precarious. We may survive if planted in a very protected microclimate—such as against a warm south-facing wall—and heavily mulched for winter protection. However, we are likely to suffer significant dieback or defoliation during colder winters and are not guaranteed to return. In zones lower than 9b, we cannot survive the winter outdoors. In these regions, we are best treated as spectacular summer annuals or grown in containers that can be moved indoors to a bright, sunny location well before the first autumn frost arrives.
Even within the appropriate hardiness zones, simply being planted in the ground is not enough for us to reveal our most brilliant colors. We demand specific conditions to truly thrive. We require full sun to partial shade; several hours of direct sunlight are crucial for the development of our most intense leaf coloration. We also need rich, well-draining soil that is consistently moist but never waterlogged, as our roots are prone to rot in soggy conditions. A regular feeding schedule during the growing season supports our vigorous growth and vibrant leaf production.
