There are 10,500 known species of ferns on the planet, though it is believed that there are a few thousand unknown species as well. They can range from tiny plants that are less than an inch tall to giant tree ferns that can reach up to 80 feet.
Of course, most of these aren’t options for growing indoors. For houseplants, you’d likely want to stick to small, yet lush types, like the Asparagus, Button, Holly, or even Tree fern varieties. Our fern growing tips can help you maintain the proper conditions to help your chosen plant thrive.
Soil
Ferns don’t need any specialty soil to get their nutrients from, though they do prefer some specific conditions. Though they love moisture, they don’t like to sit in a puddle, so well-draining soil is best.
Most varieties prefer neutral to slightly acidic conditions with a pH range of 4.0 to 7.0. This isn’t true for every variety, so be sure to check the needs of the specific plant. You can also use a compost mixture made of peat or a fibrous substitute combined with a high quantity of sand. This combination drains freely to avoid soggy roots.
Watering
As mentioned above, ferns like moisture but hate to be overwatered. That’s why it is best to check the plant every day and water as needed. If the top of the soil feels as though it is beginning to dry out, add a small amount of water. This ensures that the plant is getting the moisture it needs without soaking the roots too much and causing damage. You should never let the soil dry out completely, so check the plant daily for the best results.
Humidity
As well as maintaining moisture in the soil, you need to do so in the air as well. Ferns love humidity, so if you have a greenhouse or terrarium that you can keep at a high humidity level, this is the best place for them.
Of course, not everyone has one of these in their homes. Luckily, there is another option to keep your fern moist and healthy. You can place a humidifier near the fern to keep it happy or mist the fronds every few days. Keep an eye on the fronds since brown tips and reduced growth can be signs of low humidity levels.
If all else fails, place your fern into a bathroom or a kitchen that can give it the light it needs as well as a decent amount of moisture. These rooms have the highest humidity levels in the house, so are the best places for a fern.
We also have some tips for increasing the relative humidity levels in your home in a separate article.
Lighting
Ferns are used to the shady areas of the forest, so they don’t like a ton of sunlight. This doesn’t mean that you should stick them in a shady corner and forget about them, though. They do still need some sun to survive.
The best place for a fern is close to a window that gets sun in the morning or late afternoon such as a westerly facing window. This gives them the light they need without overheating. Any more than this and the soil will dry much faster, requiring more frequent watering. Too much direct sunlight could also cause yellow fronds or loss of leaves, so watch for these issues and move the plant if needed.
Temperature
Despite their love of high humidity, ferns don’t all need overly warm temperatures. If you’ve chosen a tropical or sub-tropical species, a room with a temperature of 50 to 70 degrees Fahrenheit is best. These plants do best indoors as they get a more consistent temperature than when planted outside.
Fern varieties from the more temperate areas prefer temperatures of 50 to 60 degrees, but a little warmer likely won’t cause any issues. Of course, no ferns like the cold, so keep them away from windows or drafty areas, especially in the winter.
Fertilizer
Fertilizer isn’t necessary to keep your ferns thriving, though they can handle a bit of this once in a while to help maintain their green coloring. Don’t use anything too strong, though, since this could damage their delicate root system.
Instead, use a slow-release fertilizer once a month from early spring to the middle of autumn. You can also try a liquid houseplant fertilizer but only at half-strength to keep those roots happy and healthy. Don’t use any fertilizer during the winter since most fern varieties will have entered their resting stage and halted their growth.
Repotting
Repotting your fern will likely become necessary as your fern grows in size. It will eventually become too large for its pot, so a larger one is a must to keep those fronds growing in size. Of course, this isn’t necessary until the roots have filled the pot, so don’t judge this by the frond size alone.
The best time to repot your plant is in the spring. If you want smaller plants, you can split the fern into two and give them each their own pot to expand in, this is propagation which we’ll touch on below. You can also move the whole plant into a larger container for an even larger fern.
When moving, carefully break out the soil around the plant and gently remove the roots. Don’t pull on the plant as this can damage it. It should be able to be gently removed from the soil. Once it’s in its new home give it a healthy dose of water and keep it protected from direct sunlight. Your fern will be at its most vulnerable to sun damage for a week or two after repotting.
Propagation
There are three methods of propagation when it comes to ferns. The first is division, which is done by dividing a clump of smaller fronds from the main plant. This is the easiest method, giving you an already grown plant instead of starting from scratch.
You can also use the stolons to create new plants. The stolons are long, string-like structures, which can be layered on the soil until they root and new growth begins to appear. Then you can cut them from the main plant and move them wherever you like.
The most difficult and time-consuming method is using the spores that grow beneath the fronds to begin new plants. This is basically like planting new seeds, so they need extra care, though you can get several new plants from one frond. This makes this the best method if you want to grow a lot of ferns at once.
Indoor Fern Growing Tips
Ferns are excellent indoor plants that are quite hardy and easy to grow. They don’t take much effort, and make a great choice for even first time gardeners. Have you grown ferns indoors before? Let us know how it went and what variety you grew!
FAQ
Why Are My Fern Tips Yellowing?
This is often due to too much direct sunlight. Try moving your plant back from the window a bit to see if the condition improves. If not, it can also mean you’re watering the plant too much.
What Is The Best Fern To Grow Indoors?
Boston ferns are some of the most popular have that traditional fern look most people think of.
How Much Sunlight Do Ferns Need?
Look to get about 4+ hours of in-direct sunlight for most fern varieties. Certain kinds can take more however, so make sure you know which variety you’re planning to grow.
