Boston Fern Fertilizer – Tips For Fertilizing Boston Ferns


By: Heather Rhoades

Boston ferns are among the most popular houseplant ferns. This brings about the question of how to fertilize Boston ferns. Keep reading to learn the best practices for fertilizing Boston ferns.

How to Fertilize Boston Ferns

Boston ferns, like most ferns, are low feeders, meaning they tend to need less fertilizer than other plants; but just because they need less fertilizer doesn’t mean that they don’t need to be fertilized. Fertilizing Boston ferns properly at different times of the year is essential to growing beautiful Boston ferns.

Fertilizing Boston Ferns in Summer

Summer is when Boston ferns are in their active phase of growth; more growth means a higher need for nutrients. In the spring and summer, Boston ferns need to be fertilized once a month. The proper Boston fern fertilizer to use in summer is a water soluble fertilizer mixed at half strength. The fertilizer should have an NPK ratio of 20-10-20.

During the summer you can supplement the monthly Boston fern fertilizer with slow release fertilizers. Again, when fertilizing Boston ferns, administer the slow release fertilizer at half rate recommend on the fertilizer container.

Fertilizing Boston Ferns In Winter

In the late fall and through winter, Boston ferns slow their growth significantly. This means that they need less fertilizer to grow. In fact, fertilizing Boston ferns too much during the winter is often the reason that Boston ferns die in the winter months.

During the winter fertilize Boston ferns once every two to three months. Once again, you will want to fertilize your Boston fern at half the recommended rate on the fertilizer container. The proper Boston fern fertilizer for winter will have an NPK ratio between 20-10-20 and 15-0-15.

In the winter it is also recommended that distilled water be used once a month to water the Boston fern to help flush out any salts that may have built up in the soil due to the Boston fern fertilizer that has been used.

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The 5 Best Fertilizers for Ferns

Not all fertilizers are created equal. The difference between the best ones out there and an average one is drastic. With a quality product that has the ideal nutrient ratios, your fern will grow strong and healthy.

In this article, I will be reviewing the top products for ferns. Using the proper fertilizer is of utmost importance in the health of your fern as it is literally the nutrients that your fern is using to grow. Unfortunately, many products on market try to cut corners by using cheap ingredients to deliver nutrients. I’ve done the legwork in compiling a list of the highest quality products to help your fern flourish.


Fern Signals

Both overfertilizing and underfertilizing a Boston ferns affect the foliage. Too much fertilizer turns fronds brown, beginning at the tips not enough fertilizer causes fronds to lose their color and become a pale green. Boston fern requires supplements containing nitrogen, phosphorous and potassium on a regular basis to keep it healthy and lush. Supply these through a water-soluble fertilizer when fronds begin to lose their color or at regular intervals, depending on the season.


How to Grow Boston Ferns Indoors

Most of us grow our Boston ferns indoors, only putting them outdoors during the summer. Their preferred temperature range is 60⁰F - 75⁰F so refrain from moving your plant outdoors until the night time temperatures reach 60⁰F. In the fall, move it back indoors when the night temperatures start to fall below 60⁰F. Place them in a shady or semi-shady spot in your yard.

Indoors Boston ferns need filtered sunlight rather than the shade they prefer outdoors. An east facing window is ideal because the plants will only get morning sun. The rest of the day they will be in the shade. If you only have west or south facing windows, hang a sheer curtain in the window to cut down on the amount of sun your plant receives.

Humidity is also critical. Our homes are much dryer than their natural environment. Be sure to place your plant well away from heating and air conditioning ducts which will blow dry air on them. Bathrooms and kitchens, which are more humid than the other rooms of our homes, are great places for Boston ferns.

You should plan on providing extra humidity for your plant. You can mist it regularly. Or you can construct a humidity tray which is simply a (ornamental) gravel filled tray that is filled with water. The plant is placed on top of the gravel. As the water evaporates from the gravel, it provides humidity for the plant. You will need to refill your humidity tray regularly.

Use well-drained potting soil and keep it moist but not soggy. Soil that is too wet will cause root rot.

You will need to fertilize. A balanced slow release fertilizer is the easiest way to fertilize your plant. If you prefer liquid fertilizer, add it full-strength on a monthly basis. You can also dilute the fertilizer and apply it every other month instead. You will know if you are over-feeding your fern because it will start to develop brown tips on the ends of its fronds.

Thanks to their arching fronds, Boston ferns are stunning when displayed on pedestals or in hanging baskets.


How to Care for Boston Ferns

Last Updated: November 3, 2020 References Approved

This article was co-authored by Melinda Meservy. Melinda Meservy is a Plant Specialist and the Owner of Thyme and Place, a botanical boutique offering plants and gifts in Salt Lake City, Utah. Before starting her own business, Melinda worked in process and business improvement and data analytics. Melinda earned a BA in History from the University of Utah, is trained in lean and agile methodologies, and completed her Certified Professional Facilitator certification. Thyme and Place offers indoor plants and containers, a fully stocked potting bench, and tips on plants to suit your space and lifestyle.

There are 12 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 21 testimonials and 100% of readers who voted found it helpful, earning it our reader-approved status.

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Some people seem to naturally have a green thumb, or a gift for gardening, and their homes are filled with luscious, healthy greenery. If you aren’t one of those people, don’t worry – there are plants that even you can keep alive! The Boston fern is one of those plants. It’s one of the most popular ferns to grow, and its long, feather-like branches add vibrancy to any space. You can help your Boston fern flourish inside or outside of your home with just a little bit of knowledge and some TLC.


A Guideline To Care Boston Fern Outdoors

With ultimate care, Boston fern will thrive outdoors. Here is the Boston fern care that you can use to grow them outdoors.

Soil: Boston ferns prefer light, loamy and airy soils. You can add compost to your potting mix for best results. Add perlite and peat moss to the soil to improve airflow to the roots. These also ensure proper drainage after watering. Your soil should have a proper balance of the soil amendments without using too much of anything.

Watering: Boston fern is drought tolerant thus it requires plenty of water. Always provide adequate water to keep your soil moist not too much or too little. Do not allow the soil to become too soggy by overwatering because this will kill the fern. If you live in a dry climate, make it a habit to mist the plant lightly on hot days. If you are growing your fern in a container, it will need watering daily in the summer season.

Fertilizing: Use small amounts of fertilizer because the Boston fern is a light feeder. If the leaves turn pale or yellowish, it is an indication that the plant is lacking enough nutrients. Feed the fern frequently throughout its growing season. Use a dilute mixture of water-soluble fertilizer or provide a slow-release fertilizer in spring.

Pest control: Boston ferns are pest-resistant but are susceptible to damage by slugs. If you notice a light slug infestation, pick the pests off the plant early in the moving or late evening. Drop them in a bucket of soapy water to eliminate them. You can also use other non-toxic methods to discourage pests. For example, sprinkle dry eggshells or dry coffee grounds, or non-toxic slug pellets around the slug.

Temperature: Boston ferns prefer temperatures between 60-75 degrees. If you live in a region that the temperature falls under 55 degrees in the Winter, you will need to grow your ferns in pots. This is to help you move them inside to save them from frost when it starts to get cold outside. Once inside, do not place your pots near open places or vents. The cold wind blowing on them through these spaces will affect the health of your ferns.

Re-potting: The size of the pot you choose is what determines the space that the roots will have to grow. This also determines the size of your fern. If your fern is in a small pot, re-pot it when it begins to look like it will split the sides of the container. Always re-pot into a bigger pot each time to allow more growth than the previous one. If you don’t want your plant to grow larger, remove it from the pot, shake off the soil, and trim back the roots. With the right care, the fern will recover from the root pruning stress and bloom. Choose a container that has lots of drainage holes.


Watch the video: Boston Fern Care. Fern Friday


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