8 tree ferns to grow in pots or in the garden
The ferns are one of the most amazing plants in the world: its trunk is more or less thin, but its leaves can overcome smoothly two meters long. From afar, they look like palm trees, but don’t be confused as they have nothing in common (palms are angiosperm plants, and ferns are gymnosperms).
These plants are also much older; moreover, fossils of about 420 million years have been found. They don’t produce flowers, but that hasn’t stopped them from being one of the most beloved plant beings in gardens, patios and terraces. Next I will introduce you to the most popular species.
What are ferns?
A fern is a gymnosperm plant characterized by having large fronds (leaves), usually pinnate, and generally greenish in color. They may or may not have a stem that serves as a trunk, which is formed by a rhizome of roots. They reproduce by spores, which are produced in the sporophylls and are found on the underside of the pinnae, and they look like this:
Do you see those reddish dots? They are called sporophylls, from which spores arise.
Where they live?
Ferns live in the shady and humid regions of the world. However, the vast majority of tree ferns only grow in those that are temperate or warm (including tropical).
Types of tree ferns for the garden or pot
Blechnum gibbum
Image – Wikimedia/ Krzysztof Ziarnek, Kenraiz
Known as blecno or strong fern, it is a fern native to New Caledonia characterized by having a very dense crown, composed of 3-4 meter long green fronds. Its trunk is short, up to 1 meter high by about 20 centimeters thick.
Its cultivation is quite simple: it requires a fertile, humid soil (do not let it dry out completely in summer), and as if that were not enough, it resists both weak frosts (up to -3ºC) and high temperatures (38ºC).
Cyathea australis
Image – Flickr/ Pete The Poet
Known as a rough tree fern, it is a plant native to southeast Queensland, New South Wales and southern Victoria in Australia. It can reach 12 meters in height, rarely 20 meters, with a trunk thickness of about 30cm. The leaves are long, 4 to 6 meters long, the upper surface is dark green and the underside pale green.
It is grown both in gardens and in pots, with fertile and well-drained soils. The frequency of irrigation must be high, since it does not withstand drought. On the other hand, it does withstand weak frosts down to -3ºC if they are punctual and of short duration.
Cyathea arborea
Image – Wikimedia/ Xemenendura
Known as the giant fern or shrimp stick, it is a fern native to the Antilles that can reach 9 meters in height, with a thin trunk between 7 and 13 cm thick. The fronds reach a length of up to 4 meters, and are green.
Due to its origin, its cultivation is delicate. Live outdoors only in humid tropical climates, without frost. It can also be kept indoors, for example in an interior patio, protected from the sun. It requires very frequent waterings.
Cyathea cooperi
Image – Wikimedia/ Amanda Grobe
Known as Queensland Tree Fern, Australian Tree Fern, Lace Tree Fern, Scaly Tree Fern or Cooper Tree Fern, it is a native Australian plant. It grows up to 15 meters in height, with a trunk thickness of up to 30cm. Its fronds are green, with a length of 4-6 meters long.
It can be grown in semi-shade both in gardens with fertile soil and in large pots in temperate climates. It resists frosts of up to -4ºC if they are punctual and of short duration. Keep in mind that at these temperatures it can lose foliage, but it recovers well in spring. High temperatures (30, 35 or even 38ºC) do not affect you if you have moist soil.
Cyathea dealbata
Image – Wikimedia/ CT Johansson
Known as the silver fern tree, silver fern, kaponga or pong, it is an endemic plant to New Zealand. It can exceed 10 meters in height, with a dense crown composed of fronds 4 meters long, white or silver on the underside. Its trunk does not exceed 30 centimeters.
The care it requires is similar to that of its sister C. cooperi: fertile soil or substrate, frequent watering, and being in an area where the climate is temperate. It resists weak frosts down to -2ºC, although it prefers that it does not drop below 0º.
Cyathea medullaris
Known as the black fern tree, it is endemic to New Zealand. It grows to a height of 6-7 meters, with a totally black trunk that does not thicken more than 35cm. Its fronds or leaves measure up to 5 meters.
It is a relatively easy plant to care for, which requires warm-temperate climates, frequent waterings, and a soil rich in organic matter.
Dicksonia antarctica (now Balantium antarcticum )
image – Flickr/ Jungle Garden
Known as Dicksonia, it is a fern native to Australia, specifically New South Wales, Tasmania and Victoria. It can reach 15 meters in height, although it is normal that they do not exceed 5 meters. Its trunk thickens about 30cm, and is crowned with very long fronds of 4 to 6 meters.
It is often found in temperate gardens, with mild climates (with maximums of up to 30ºC) and humid. It requires a soil rich in organic matter, and frequent watering. Its cultivation in the Mediterranean is not recommended due to the low tolerance to extreme temperatures (of a minimum of 35-38ºC) that it has. For the rest, it resists freezes down to -5ºC.
Fibrous dicksonia
Image – Wikimedia/ CT Johansson
Known as the golden fern, it is a fern native to New Zealand that reaches 6 meters in height, with a trunk thickness of 30cm. The fronds or leaves are 3 to 4 meters long, making it undoubtedly one of the smallest tree ferns.
Its cultivation consists of having it in fertile, well-drained, and humid lands. Irrigation must be frequent. It resists weak and occasional frosts of up to -2ºC.
Related article:Cyathea tomentosissima, a tree fern that will not leave you indifferent
How to grow tree ferns?
Tree ferns are plants that, although there are many different species, all require more or less the same care. This means that if you buy for example a Blechnum and later get a Cyathea, I am almost 100% sure that both will be precious if you take care of them in this way:
- Location:
- Outside: place it in a bright area, but protected from direct sun. The ideal is to put it in the shade of a large tree -and wide crown-, or under a shading mesh.
- Interior: the room must be bright, without drafts.
- Watering: frequent, especially in summer. You have to keep the soil moist except in winter or if you have it indoors, when it is better to let it dry out a bit. Use lime-free water if possible, and do not wet the leaves.
- Subscriber: in spring and summer with organic fertilizers, such as guano.
- Planting or transplanting time: in spring, when the minimum temperature rises to 15ºC.
- Pests and diseases: they are very resistant. But you have to control the risks, and if the environment is very dry and hot, to the mealybugs.
- Multiplication: by spores in spring, which have to be kept in a seedbed near a heat source.
Where to buy tree ferns?
These plants are usually sold in nurseries, but from my own experience I recommend that you search the Internet for nurseries or online stores that are producers and that are dedicated to sale.
Be very careful when buying large specimens, as they may have been illegally taken from their respective habitats. To avoid taking risks, always look for small specimens, without a trunk, since this ensures that these seedlings have been obtained by spores.
And with this we are done. Which of the tree ferns you have seen did you like the most?
