Rabbit’s foot fern (Davallia Fejeensis) is hardy only in U.S. Department of Agriculture plant hardiness zones 10 through 12, but produces an impressive mountain of lacy green foliage in a wicker basket onto a screened porch or hanging in shady gardens which never see frost. These natives of the Fiji islands have needs, though. Among other causes, too little humidity or too much sunlight can dry the delicate fronds starting at their tips.
Epiphytes and Humidity
Named for the white, fuzzy rhizomes that cover the soil surface and also trail over pot sides, rabbit’s foot ferns are epiphytes — they carry moisture in the air around them as opposed to from dirt, so that they are typically stored in a pot — hanging at a tree or indoors. Foggy days provide plenty of humidity, however, indoors, humidity plummets if the central heating begins through a cool spell in sunlight. Misting helps only temporarily — it doesn’t provide the constant 40 to 50 percent humidity which ferns need. When lack of humidity causes browning hints, add humidifiers and separate plants to permit free flow of air — and humidity — around fronds.
Supplement aerial humidity by keeping growing media moist. Too little moisture may cause tips to dry out and brownish. Grow rabbit hair ferns, indoors or outside, in sphagnum moss, peat moss or bark, or a mix of those materials. Frequently labeled for orchid culture, epiphyte mixtures hold moisture but allow water to drain through. In a hanging basket lined with sphagnum moss, permit the surface of the press to become nearly dry, particularly from fall to late winter when growth slows. Rabbit’s foot ferns are sensitive to salt, so when fronds begin browning at hints, bring them indoors. Water with delicate or bottled drinking water.
Bright websites, Cool Nights
Unlike ferns that grow in shade to the forest floor, epiphytes rise in the trees, up where the lighting is bright and sometimes sunny. When they can not hang in a tree outside, hang square-foot ferns close a west or, in winter, southern window to give them four to five hours of bright light or reflected sunlight — direct sunlight will burn frond tips. Temperatures increase and humidity falls close to the ground, so hang ferns where daytime temperatures don’t exceed 72 degrees Fahrenheit to avoid dried, browned hints. Ideal nighttime temperatures range 10 degrees lower, but colder temperatures may brown leaf tips, too, so bring outdoor dwellers in when temperatures drop below 60 degrees at night.
Light Menu Eaters
Planted in a crook of a tree, a rabbit foot fern requires little in the way of fertilizer. Indoors, implanted in sphagnum moss and pine bark, leaves can begin to pale whether the plant requires nutrients. Too much fertilizer scorches fronds, however, browning them, tip-first. A 20-20-20 houseplant fertilizer must keep your plant healthy when you bring it indoors. Dilute the food by half — a half teaspoon per gallon of water if the label indicates a teaspoon per gallon, like — and water over a pan for drips once per month between March or April through October.