Top 5 Tropical Ferns

Create An Oasis in Your Home With Tropical Indoor Ferns

Tropical ferns are some of the oldest types of plants on the planet. Fern fossils have been found that are 325 million years old! There are 10,000 species of ferns existing now on earth and each species has its own unique height, shape and growing environment. They are air purifying rainforest plants that have found their way into our garden centres and are enjoyed in our homes.

Many species of ferns are epiphytic in their natural rainforest habitats. You will find epiphytic ferns in the tree canopies, taking in nutrients from the air and rain.  Ferns can also be found on the rainforest floor, providing lush humid environments that they share with the rainforest creatures.

Many people shy away from purchasing ferns thinking they are too much of a challenge. In reality they have minimal care requirements. You only have to provide a few key basics to put you on the path to fern growing success!

Most of the tropical ferns you find in garden centres will be happy at indoor temperatures between 18 and 24 C with 10 degree cooler night temperatures.

Location – Ferns love a bright, warm and humid indoor location. Do not put your ferns in direct sun. A few will tolerate lower light levels. In spring and summer an east window or west facing location further back from a window is ideal. In winter you can put them closer to a west or south facing window.

Ferns love humidity.  This does not mean you have to turn your home into a sauna! It can be a bit of a challenge to have a happy fern in our dry homes (especially in winter) but the purchase of a small tabletop humidifier can remedy that. Group your ferns together around a small humidifier, leaving some room for air flow. A relative humidity of 40-50% will keep most ferns happy and thriving. Include a small fan in the same room to increase air movement around the plants. If you are fortunate enough to have windows in your kitchen and bathroom, these are the ideal rooms for ferns. I have a shelf in the window above my kitchen sink where just about any plant loves to live. It is ideal for ferns! I am not a big fan of misting your ferns to provide humidity. Most of the mist is wasted into the air and would have to be done at regular intervals throughout the day to be effective. In winter, at watering time, give your ferns a shower to remove any dust accumulation.

Watering - It is important to keep indoor ferns moist at all times. Moist does not mean overwatered and soggy. Too much water can eventually cause root rot and kill a fern. When the top of the soil is beginning to dry, water with warm water. Never let a fern completely dry out. Make sure to empty the drainage trays after you water.

Pots – Plastic pots or glazed clay pots are ideal for ferns. Terra cotta clay pots dry out way too fast.

Soil – The optimum soil for ferns is a very porous and fast draining soil mix that will retain some water (think “moist”). A rich tropical plant soil, with extra perlite and even some medium orchid bark mixed in will help provide the aeration that fern roots need to survive. A neutral  pH soil is fine but some ferns require a slightly acidic soil mix. For those ferns add dampened peat moss to the soil mix.

Fertilization –  Ferns require very little fertilizer. Provide a half strength application of an all- purpose water soluble tropical plant fertilizer once a month in spring and summer only.

Propagation – Ferns do not flower or produce seed. Fern propagation is usually accomplished by root division or starting the spores that grow on the underside of the fronds.**  Root division is most often used as spores can take months to germinate and grow. Root division is best done in spring and summer. Do not forget to sterilize your tools. Each division should have fronds and healthy roots. 

Bluestar Fern – Phlebodium aureum

Height: 60-90 cm.    Width: 60-90 cm.

This fern is one of my favorites. It is native to the rainforests of South America and is an epiphytic fern. Like staghorns, it can be mounted on a board and hung on the wall or grown in a pot.

I would suggest bottom watering this fern as the exposed hard rhizomes at the top of the soil do not like to be wet. Sit the pot in warm shallow water until the top of the soil is damp.

Your Blue Star fern will need repotting when the rhizomes push against the sides of the pot, causing it to become misshapen. The new pot size should only be one or two sizes up from the old pot size. A very large new pot will hold too much water, over saturating the soil mix and cause root rot.

When dividing a Blue Star fern root ball, wash any soil mix off the root ball with warm water. This fern grows in sections; it does not have a central root system. Carefully pull apart the sections of the root ball. Each section should have roots, stems, and leaves/fronds.

Wimsettii Fern  -  (Pteris cretica “Wimsettii”)

Crested Cretan Brake Fern

The Crested Cretan Brake Fern is native to Africa, Asia and Europe

Height: 30 – 60 cm.          Spread: 30 – 60 cm.

This Brake Fern is a clump forming fern with an arching green mound of palmate leaves with the leaflets being long, slim and flat. Each leaflet has a crested tip.

Place this fern in a dappled shade to shady location. It can tolerate some bright indirect light.

The cultivar ‘Mayii’ is more commonly known as the Ribbon Fern. The variegated green fronds are divided and have crested leaf tips.

Silver Lace Ferns (Pteris ensiformis “Evergemiensis”) are green with silver variegation.

Propagate by root division and spores.

Brake Ferns are easy to grow and an ideal starter fern for beginners.

Tiger Boston Fern  -  Nephrolepis exaltata ‘ Tiger Fern”

Variegated Boston Fern

Height: 30-60 cm.          Width: 60-90 cm

Green fronds with chartreuse to yellow variegation.

Place in a location that has part shade to bright indirect light.

If the soil is allowed to dry out, the Tiger Fern will shed some fronds. If too many fronds are lost, cut the remaining ones back to 5 cm in height to rejuvenate the fern. You can then repot the whole rootball or propagate by root division. You may have to use a very sharp sterilized knife to cut the root ball in half or in quarters. 

In their native habitats Boston Ferns may grow 2 meters! They are native to Florida, Mexico, West Indies, Africa, Polynesia and Central/ South America.

Lemon Button Fern    -      (Nephrolepis cordifolia ‘Duffii’)

Native to Asia

Height: 30 cm          Spread: 30 cm

A slow growing rhizomatous small variety of Boston Fern. When crushed, the fronds give off a lemony scent.

Place in bright, indirect light. Will tolerate somewhat lower light levels as well.

Soil should be loamy, moist, and very porous. It likes somewhat acidic soil (peat based) but can tolerate less acidic soil if necessary.

Some fronds may die in winter. Just remove these fronds at soil level with sterilized pruners or scissors.

Crocodile Fern  -  ‘Microsorum musifolium’

Height: 60-90 cm.          Spread: 60-90 cm.

Native to the Malaysian Archipelago.

The Crocodile Fern has unique, reptilian textured, wide glossy leaves. An epiphytic fern, it predominately grows on the rainforest floor.

It belongs to the same fern family – Polypodiaceae – as the Staghorn Fern and Blue Star Fern. The fronds are long and leathery.

Use a porous, rich organic potting mix. A mix designed for orchids or epiphytic plants works well as it allows for good air circulation around the roots.

Avoid cold drafts and sudden temperature changes.  Maintain an indoor temperature between 16 – 24 C.

Repot every 2-3 years or when the plant is root bound. Repot into a container that is one or two sizes up from the original.

Propagate by division or spores. Use lukewarm water to wash away the soil from the roots so you can see the natural root divisions of the plant. Identify the sections of the fern root that can be separated. Each division should have fronds and a healthy root system.

Troubleshooting Fern Problems

Fronds are small and growing slowly – too little light.

Scorched fronds – too much sun.

If the fronds (leaves) become brown and crispy, the fern is probably in too much light or does not have enough humidity. The leaves will become pale if there is not enough light provided.

Browning frond tips are caused by low humidity and possibly not enough water.

Wilting fronds – too much water – too much sun.

Mushy stems – overwatering.

Yellow leaves - too much sun and or too much water.

Fern spores are often mistaken for scale insects. Mature spores can be many colors depending on the fern variety. They are usually round and appear in rows on the underside of the fronds. Scale will attack both the top and bottom of leaves and secrete a sticky honeydew.

Regarding Fern Toxicity

I always advise people to research the toxicity of the plants you have in your home and consult your doctor or vet. There is also a Sask Government Poison Information Centre that is available 24/7, all year round.

**There will be more information on fern spore propagation in October’s DIY blog.