By: Mary H. Dyer, Credentialed Garden Writer
Ferns are beautiful, ancient plants that have been around for many millions of years. They are versatile plants that grow in an amazing variety of conditions, and many are well-suited for growing indoors. Although ferns are hardy specimens, they require a bit of care to keep them looking their best. Fertilizing indoor ferns isn’t complicated, but it helps to be armed with useful information, such as the best fertilizer for indoor ferns, and when to feed fern houseplants. Keep reading to learn all you need to know about fertilizer care for ferns indoors.
How to Feed Your Indoor Potted Ferns
In their natural environment, fern plants draw nourishment from a steady diet of decaying leaves and other organic matter. Although regular fertilization is important, indoor ferns don’t need heavy doses of fertilizer, which may scorch the leaves.
Be sure to water well immediately after fertilizing indoor ferns; fertilizer is a strong chemical that may damage the roots when applied to dry soil.
When to Feed Fern Houseplants
If your fern is newly potted (or repotted), allow the plant time to adjust to its new environment before fertilizing. As a general rule, it’s a good idea to wait four to six months, but you can start earlier if growth is really taking off.
Thereafter, fertilizing indoor ferns is best done every month throughout the growing season. Feed the plant only every other month when growth is slower during fall and winter.
What is the Best Fertilizer for Indoor Ferns?
Indoor ferns aren’t terribly fussy about their diet, and a weak dose of any liquid houseplant fertilizer is just fine. Be sure to dilute the fertilizer to about half the mixture recommended on the label.
This article was last updated on
Read more about Fern Houseplants
Factsheet | HGIC 1505 | Updated: Aug 21, 2015 | Print | Download (PDF)
Ferns are an attractive addition to any home or office. Ferns are popular because of their graceful foliage and ability to grow in low light. Many different types of ferns can be grown indoors for interior decoration.
The Boston Fern (Nephrolepis exaltata ‘Bostoniensis’) is commonly grown in hanging baskets.
Barbara H. Smith, ©2015 HGIC, Clemson Extension
How to Care for Ferns
Last Updated: November 17, 2020 References Approved
This article was co-authored by Artemisia Nursery. Artemisia Nursery is a retail plant nursery in Northeast Los Angeles specializing in California native plants. Artemisia Nursery is a worker-owned small business with plans to become a worker-owned cooperative. In addition to California native plants, Artemisia Nursery offers a selection of succulents, heirloom veggie and herb starts, house plants, pottery, and gardening tools and supplies. Drawing on the knowledge of the founders, Artemisia Nursery also offers consultations, designs, and installations.
There are 14 references cited in this article, which can be found at the bottom of the page.
wikiHow marks an article as reader-approved once it receives enough positive feedback. This article received 26 testimonials and 92% of readers who voted found it helpful, earning it our reader-approved status.
This article has been viewed 557,660 times.
Taking care of a new plant is never easy, especially if you aren’t familiar with what they need or like the best. Ferns are beautiful, shrubby plants that thrive in warm, moist environments either inside or outside. There are tons of different species of ferns, but they all generally need the same thing: water, warmth, and shade. By putting your fern in the right spot and keeping an eye on it, you can grow your fern to its full potential and keep it around for years to come (seriously—some ferns can live to be 100 years old!).
Best for Lawns: Scotts Turf Builder 12.6 lb. 5,000 sq. ft. Lawn Fertilizer
It’s hard not to envy your neighbor whose lawn is always thick and luscious, but you can get the same healthy grass with the help of Scotts Turf Builder. Scotts is one of the top brands for lawn fertilizers, and this particular product helps to thicken grass and provide even greening, all while crowding out weeds.
A 12.6-pound bag of Turf Builder can cover up to 5,000 square feet of lawn, and it can be used on all grass types. It provides nutrients to your grass, helping it to grow deep strong roots, which in turn helps to strengthen your lawn against heat and drought. This fertilizer has an NPK ratio of 32-0-4, and it can be applied in any season and lasts for up to six weeks. Just be sure to follow the instructions, as applying too much can burn your grass.
Fern Plant Food
As a plant meal, compost serves up a full course of benefits. First, it provides important nutrients, such as nitrogen and phosphorous, to your fern's roots. For the best results, mix a couple of inches of compost or similar well-rotted organic matter into the top 10 inches of soil before you plant your ferns. Ferns have delicate roots and don't respond well to high dosages of nutrients all at once. Ferns grown as indoor houseplants require a different feeding schedule compared with their outdoor counterparts. Once you see new growth appear on your potted fern, begin fertilizing it once a month until new growth stops, typically in the late fall. Use any liquid houseplant fertilizer. Think of mulch as the dessert in your fern plant's multi-course meal. Mulch conserves soil moisture and regulates soil temperature, helping to create the moist, cool environment that many ferns enjoy.
Plant asparagus ferns in pots or containers in loose, well-drained potting soil. Outdoors, plant it in rich, well-drained soil that is slightly acidic. It is generally tolerant of less-than-ideal soil conditions.
Asparagus ferns don't mind being slightly pot-bound, and can go up to two years before repotting. For the most successful repotting, divide the plant into big clumps, and be sure to take multiple underground roots when dividing. Place the divided plants into similar-sized pots to retain the tight growth habit. Asparagus ferns do not need large pots, as they are slow indoor spreaders.
3. Provide Ferns With Consistent Water and Humidity
If you've always got the urge to water your houseplants, ferns will do well under your care. They like evenly moist soil, and while you shouldn't water them constantly, don't let them completely dry out between waterings either (there are some exceptions, like brake fern, rabbit's foot fern, and Japanese holly fern, which don't mind drying out between waterings). To figure out if you should add water, stick your finger into the soil about an inch deep. If it's dry, give your fern a drink, and if it's still damp, wait a couple more days.
Most tropical ferns also do best with high humidity. They naturally do well in bathrooms, thanks to steamy showers, but you can also mist their foliage with room temperature water once or twice a day. Or invest in a humidifier to increase the humidity in the whole room if the air tends to get really dry in your home.