Ferns are some of the oldest plants in the world—they've been thriving for 300 million years and grow in an astonishing array of environments. As houseplants, they've been in cultivation for centuries. Worldwide, the American Fern Society estimates there are about 12,000 species of ferns, ranging from cold hardy to tropical, and ranging in size from miniature to the monstrous tree ferns of New Zealand and Australia. Growing most ferns isn't difficult—certainly no more difficult than keeping orchids alive. There are, however, a few basic pointers you need to follow to have success with most of the common houseplant ferns available:
- Humidity is essential. None of the popular household ferns can tolerate dry conditions for long. Their fronds will quickly turn brown, and they will begin to drop leaves. Mist your ferns as often as practical, preferably in the morning.
- Never let your ferns dry out. Most ferns are adapted to the loamy understory of forests and rainforests. Even the epiphytic ferns, such as the staghorns, tend to thrive in the loamy leaf litter that collects in the crooks of tree branches. So make sure your ferns are well hydrated. However, a word of caution: unless it's a bog fern, don't let your fern sit in water. Keep it damp, not soggy.
- Give them light. Contrary to popular opinion, ferns are not typically deep shade plants. They are adapted to the dappled sunlight of the forest floor. So make sure your fern is getting enough bright, filtered light to thrive. On the flip side, however, few ferns can withstand full midday sun and will quickly begin to turn brown.
- Feed your ferns. As forest floor plants, wild ferns thrive on a steady supply of gently decaying organic matter. In the home, this means giving them a steady supply of weak fertilizer during the growing season. A weak liquid fertilizer or slow-release pellet fertilizer is perfect.
Beyond these basics, each genus of ferns has more specialized requirements. So make sure you know what you're growing, and then provide the right elements. You'll be rewarded with an indoor garden of unparalleled lushness and delicate beauty.