Though some call it cathedral windows and some call it the peacock plant, there’s little chance of anybody calling Calathea makoyana dull. Translucent, creamy-green foliage patterned using a darker, intricate leaves-within-leaves design gives the plant its own rose-window splendor. As if which weren’t enough, the design repeats in pinkish-purple on the leaf’s undersides. Regrettably, like the leaves of this poet Robert Frost once observed, “Nothing gold can stay,” cathedral windows’ foliage dries out and dies as it ages. Cultural problems have a similar effect. Removing the damaged or tired leaves and supplying the right growing conditions promotes vibrant new growth.
Eliminating the Leaves
Eliminate the old, dead or dry leaves from your cathedral windows once they occur. Use clean, sharp scissors to cut them away in the base of their reddish stems. To avoid spreading insects or disease, dip the scissor blades in a solution of 1 part household bleach to 9 parts water between cuts.
Examine the remaining leaves for dead, brown tips or margins resulting from cultural problems. If you’re able to, trim the dead tissue without ruining the leaves’ appearance. Otherwise, remove the entire leaves, again disinfecting your scissors between cuts.
Determine which of the cultural practices are liable for the damaged leaves. In the wild, cathedral windows grows only in the hot, humid jungles of eastern Brazil. It tolerates outside life in U.S. Department of Agriculture plant hardiness zones 11 through 12, but does not succeed outside in colder areas without substantial pampering, though it might be grown as a houseplant.
Preventing Future Problems
Give cathedral windows a brightly lit location with no direct sun and a temperature consistently between 70 and 85 degrees Fahrenheit. Immediate sun may burn its own leaves. To keep cold air from browning and curling them, move the houseplant from air conditioning vents in summertime.
Keep the growing medium consistently moist. Lack of moisture browns and shrivels cathedral windows’ lower leaves and also causes dark, brownish spots on its upper ones. After the top 1 inch of medium is dry to the touch, water the plant thoroughly until the surplus water flows from the container’s drainage holes. Use tepid, distilled or rainwater; fluoridated water also dries the leaf tips and edges.
Provide cathedral windows using at least 60 percent humidity during winter. At lower levels, its leaves often dry and brown at the tips. Place the pot on a shallow tray full of pebbles submerged in water to just below their surfaces. Replenish the evaporating water since it raises the humidity around the plant.
Fertilize your plant every three weeks from March through September and once monthly during the rest of the year. Salt accumulation from excessive pesticide browns the leaf tips and edges. Mix 1 tsp, or the maker’s suggested amount, of granulated, 20-20-20 houseplant fertilizer in 1 gallon of water and use it to replace a normal watering session.