Calatheas make for great indoor plants, and even garden plants providing you are in a sub-tropical area. These plants originate from the South American tropics and are related to Maranta or prayer plant. The flowers of some species are quite spectacular, but most of these plants are grown for their foliage rather than the flowers. Plants that are able to tolerate very low light conditions in the home or office are limited, but the wide range of colours you can expect from calatheas more than makes up for this.
How To Grow:
Some people might find it a bit tricky to grow Calathea varieties well, but they are mostly rather easy providing they are given the right conditions. Big, broad leaves are a clear indication that these plants prefer shady conditions, although they might be able to handle some very early morning direct sun. Any direct sun or conditions that are too bright will ‘bleach’ the foliage colour. Water is the part of growing these plants with which most people struggle. They prefer to have their roots moist at all times but not soggy. If the roots stand in water for long periods, they might be susceptible to drowning or rot. High humidity is best for these plants as the leaves will quickly curl up or form dried-out patches in low humidity conditions. A potting mix that retains moisture but still drains well is best, and the plants grow optimally in chunky peat mix. A humidity tray placed beneath the plants will allow for slightly raised humidity during drier periods and will greatly benefit the plants.
Choosing the right Calathea:
If you prefer the bold contrast between deep velvety maroon leaves and orange flowers, Calathea crocata is for you.
Different shades of green can also be subtly arresting. If this is your preference then plants such as Calathea orbifolia, Calathea ‘Freddie’, Calathea ornata ‘Beauty Star’, Calathea lancifolia and Calathea leopardina might be good choices.
The best Calathea varieties for the garden are Calathea lancifolia, Calathea leopardina, Calathea sanderiana and Calathea ‘Network’. Certain Calathea roseopicta varieties will only grow in the most tropical gardens as they will get marked leaves in dry or cold conditions.
There are numerous varieties of Calathea roseopicta that do well indoors with leaves marked in green, maroon and purple.
Troubleshooting your Calathea
Dry patches or edges usually occur when there is a combination of high temperatures with low humidity. They may also be caused by cold wind.
Curled-up leaves are an indication that the plant is dry and needs watering. This is usually only temporary but if it stays dry for too long the leaves might die back.
Black and brown patches on the leaves, especially young unfurling leaves, are signs of bacterial or fungal infections. These could become a problem as the high humidity that these plants love is the perfect breeding conditions for these ailments. Treat with a systemic fungicide and ensure adequate air movement to avoid stuffy conditions.