Keep Anthuriums Blooming
Anthurium is a genus of around 1,000 species of perennial plants native to Central America, northern South America and the Caribbean. While they can be grown outdoors in the garden in warm climates, anthurium is more often grown as houseplants by enthusiasts willing to put forth the effort for a plant that can be fussy. Some species are highly prized for their bright, exotic flowers, while others are grown mostly for their foliage.
The flowering varieties of these plants are distinctive for their multicolored spathes and red or yellow tail-like flower spikes. Other varieties feature large-leaved, deeply veined foliage. Many anthuriums are climbers and all need high humidity and warmth to thrive. They tend to thrive in greenhouses, and no type of anthurium is particularly well-suited for indoor, domestic living without a lot of attention and care.
Anthurium plants thrive in bright, indirect light. They do not like exposure to direct sunlight, except in the winter months or in plants that have been carefully acclimated. Wild anthuriums generally live in temperatures at or above 60 degrees F and the foliage types prefer temperatures even warmer. If temperatures dip below this level, the plant will suffer.
Potted anthuriums prefer a rich but well-draining potting mix that should be kept moist but not wet. A potting mix tailored for orchids, with a few handfuls of sand and a few handfuls of peat moss mixed in, is ideal.
In natural settings, many anthurium plants are “epiphytic”—they grow on other plants instead of in soil. If your plant fails to support itself, give it a stake or small trellis to climb on.
Repotting should be done whenever the plant fills up its pot with roots. This can occur every year or two, when you see “air roots” begin to extend up above the soil level. This is a sign that the plant can be repotted.
Indoors or out, anthuriums grow best in bright, indirect light. Avoid direct sun, which can burn the leaves.
Anthuriums prefer a coarse, well-draining potting. An orchid mix with additional sand and peat moss mixed in, makes a perfect potting mix for anthuriums.
The soil should be kept slightly moist and never allowed to dry out completely. Setting the pot in a tray of water-filled gravel will help the plant drain and also help keep humidity levels high. Allow the top of the soil to dry out to the touch before watering again.
Temperature and Humidity
All species of anthurium are native tropical plants and mimicking those conditions will give you the best chances for success. This plant prefers high humidity and temperatures between 65 and 85 degrees Fahrenheit. These plants can be grown outside only in zones 11 – 12, and will likely perish at temperatures 40 degrees or less.
In dry climates—or during dry winter months—mist the plant daily to keep humidity levels high. You may find it necessary to run a humidifier constantly during dry months.
It is safe and recommended to use liquid fertilizer throughout the growing period. Use a fertilizer high in phosphorus, and dilute it to half strength to feed the plants every two weeks or so.
Potting and Repotting
When an anthurium fills up its pot with roots and begins to send up plentiful air roots, it is time to repot. Normally, this is necessary every two years or so. Transfer the plant to a pot that only slightly larger than the old one—no more than 2 inches larger. Fill the pot only about 1/3 full of potting mix, then set the plant onto the soil and lightly pack additional soil around the base, up to the level the plant was buried in its old pot.
As new air roots form above the soil over the following weeks, lightly pack additional potting mix around the exposed roots.
Common Pests & Diseases
These plants are subject to some of the same pests that commonly affect most houseplants: mealybugs, spider mites, whitefly and scale. Horticultural oils and soaps can be used to treat these.
If dry or drafty locations, the foliage on anthuriums may scorch. In rare cases, fungal rots, blights, or leaf spots may occur.
Information courtesy of TheSpruce.com