Many Crotons can be grown in full sun (once mature) but most do well with partial shade, and some cultivars need more shade to look their best. Excessive light on young plants will burn and scorch leaves, stunt new growth and cause eventual decline. It is also true, however, that they are most adaptable to change when they are younger, and are more likely to succeed in being able to tolerate stronger sun.
If you are uncertain where a Croton belongs, i.e., how much shade is too much or not enough sun to color the plant nicely, or conversely how much sun will end up fading or "bleaching out" its leaves by summer's end, it may be advisable to leave your Croton in a pot for a while and move it around to different garden locations to see where it's happiest. Unfortunately, the true test for Crotons in Florida always comes in the Summer months when the sun is strongest and days are the longest.
In the face of uncertainty as to a Croton's optimum garden location another approach is to plant it in a spot with shady summer afternoons (roughly noon to 4 p.m.) and if the leaves are dark and lackluster or the plant not quite thriving, then transplant it to a sunnier spot. All of our plants are grown in a 35% shade house and moved to brighter conditions as they mature.
Once planted and a Croton reaches 2-3’ in height with a good root system and a strong trunk, it is better able to tolerate harsher conditions. Young plants require more water and shading while they reach that larger size and tougher state.
Crotons require ample amounts of water while young plants but can become very drought tolerant at maturity. They are less tolerant of wet and boggy conditions, and will develop root rot if they are subject to extended flooding conditions. An irrigation system that gives plants up to 1” per week in the winter is ideal. While plants shouldn't need additional irrigation in the summer rainy season we have unfortunately been experiencing near drought conditions in Florida over the past summers. Going without any means of irrigation in the summer months particularly if you are a seasonal resident is inadvisable unless you're exceedingly comfortable gambling. Plants in containers (whether created from natural or artificial material) need water 2-3 times weekly in the winter but more often in Summer, even daily especially if temperatures exceed 95 degrees accompanied by windy conditions .
They desire a well drained soil with lots of organic matter, an acid PH of 4.5 to 6.5 and a layer of mulch to conserve moisture and reduce weed competition. Most soils in Florida are satisfactory except for high PH rock soils with calcium base. They are heavy feeders and look best when given regular applications of fertilizer.
We prefer an organic Palm fertilizer applied in early spring (March) and late spring (May) for established plants. Young plants might take a third feeding about July but do not apply late in the season. It is essential to let new growth harden off for the winter dormancy period.
Crotons are true tropical plants and perform best at 50-90 degrees. At 40 degrees the plants will enter dormancy and stop most growth. At 32-35 degrees some cultivars will drop leaves, especially in a windy, unprotected spot. At 28-32 degrees, all plants will drop leaves and some will have tip or stem damage depending on the age of the plant, cultivar and location. We have seen some varieties in Melbourne, FL keep all their leaves and experience no die back at 28 degrees while other varieties will drop all leaves and die back to the ground at 32 degrees in Ft. Pierce.
We have observed many Crotons growing just fine within 100’ of the ocean in Florida. They are rarely damaged by normal levels of salt spray but should a heavy wind blow excessive levels of salt spray on the leaves for an extended period, they can be defoliated (as can most non native sea-shore plants). A timely and thorough wash of water from the hose bib takes off most of the sea salt on your special plants.
They have been used as indoor decorative plants since the Victorian era in Europe. Their colorful foliage, hardiness and ease of care have always made them very popular worldwide. Many nurseries in North America started importing them from Europe to be used specifically as house plants. Varieties Norma, Petra and A.F.D. #5 were bred especially for the indoor environment, and are widely grown and used today for just that purpose.
Ironically however, we do not recommend Crotons as houseplants in South Florida because they must have humid conditions which centrally air-conditioned homes and offices cannot provide.
The most widely grown varieties for indoor use include Petra, Norma, A.F.D.5, Mrs. Iceton, Gold Dust, and Mammie. Dwarf varieties such as Batik, Ram's Horn and Picasso's Paintbrush are also good choices. Most people start with a one gallon plant for a table top or small space, and a three gallon plant for floor decoration. Simply take the new plant and drop it inside of a decorative container or repot into a clay, faux terracotta or other decorative pot with saucer and good drainage. Use a good sterile potting medium, finish by sprinkling a little slow release fertilizer around the top, and give the roots a good soaking once weekly.
Don’t over water or keep the soil soggy. Houseplants are happier when just a little dryer; as long as the leaves and stems are atomized frequently. If it’s in a sunny window, increase slightly. The biggest problem with Crotons indoors is spider mites. Since spider mites most often congregate under the leaves, regular humidifying via spray droplets is just the right discouragement . Once spotted, simply wiping the leaf undersides with a soft sponge and soapy water should keep them suppressed and under control.
In the warmer months when overnight temps rarely dip below 60 degrees F, potted crotons enjoy spending some time outdoors in a spot that is shaded from hot afternoon sun.