Ferns are among the most popular houseplants, but not every house is suited for them. You may find your fern fronds turning brown within weeks of bringing the plant home from the nursery. Prevent browning leaves with a knowledge of your fern's basic needs.
Ferns prefer 40 to 50 per cent humidity, but average homes have only 10 to 15 per cent humidity. Many ferns have delicate leaves that turn brown when humidity drops. Misting is not always effective. Instead, place the potted fern on a dish of pebbles or gravel. Fill the dish with water to create a humid environment without waterlogged soil.
Ferns are adapted to shady but sunlit conditions. Direct sunlight scorches the leaves, turning the entire side of a plant brown. Ensure that the fern receives filtered or indirect sunlight. A northern window is ideal. The angle of sunlight changes over time, and a fern may receive direct sun or even bright, reflected light as the sun shifts.
Despite the lush, rapid growth of many ferns, these plants are not heavy feeders. In fact, the opposite is true. Too much fertiliser burns the fronds, causing browning and dead leaves. Fertilise ferns only when they produce new growth, and use a liquid fertiliser at half the recommended dosage for houseplants. Avoid fertilising during cooler months, when fern growth slows considerably.