There is a lot of misinformation out there about maidenhair ferns (Adiantum sp.) which paints them as being finicky and easy to kill when they are actually one of the easiest plants to care for. By looking at their natural habitat you can quite quickly start to see that there are really only two things that matter when it comes to growing this super lush fern. Light and water!
Maidenhair ferns can be found natively around Melbourne. After some research, and trial and error we have figured out how to grow the perfect maidenhair fern and are ready to share our secret with you.
Maidenhair ferns need to be in a very bright position. Look for a spot where there is enough natural (indirect) light that you don’t always have to use any electric lighting to be in the space comfortably. If the room is a bit darker try to keep the fern closer to window to maximize how much light it receives. A good way to tell if it’s a good position is that you will be able to see the sky from the plants perspective.
Cool direct sun either in the morning all year round, or direct afternoon sun in winter provides a huge boost to the growth speed without burning the plant. Our maidenhair fern receives direct morning sun everyday which is how it managed to grow to this size in only three months.
Maidenhair ferns are one of the few plants that you cannot over-water! They love to be consistently moist at all times. The easiest way to achieve this is to keep a deep tray under the pot they are in (self watering pots work great for this too.)
If the tray is empty, add water to it, if it’s full then your job here is done! In summer they can drink up quite a bit of water so be sure to keep the tray topped up at all times. In winter the tray can be allowed to empty for a short time without damaging the plant.
Avoid watering onto the leaves as they may snap. Watering directly onto the soil or just top up the tray.
During the warmer months of the year, apply a liquid fertilizer every two weeks. Make sure to dilute the fertilizer per the instructions on the back. Feel free to use a seaweed extract or similar product at the same rate to elevate your plant’s health.
During winter the growth will slow down so fertilizer will not be necessary, however if you are blessed with the right conditions and your plant continues to rapidly grow then keep fertilising but consider using a weaker dosage.
Most newly purchased plants will come with a few months worth of slow release fertilizer already in the soil.
Due to the maidenhair water requirements it is easiest to get a pot that comes with a deep tray or self watering feature unless you want to water it everyday. It’s always better to re-pot during the warmth of spring and summer when the plant is actively growing but I haven’t found this plant to be particularly sensitive to being re-potted at other times of the year provided it is a well established plant is well looked after. (If you have any well researched resources on re-potting ferns please send them our way.)
Simply massage the plastic nursery pot to help it release and slide the root ball free. The root ball may stay in a solid cylinder shape due the matted form of the roots holding all the soil together. You do not need to tease the roots or loosen the soil up to encourage growth. Simply place it into it’s new container and fill in the spaces.
The large plant featured in the comparison is in a 16cm in diameter and 16cm tall pot. The small plant is in a 14cm x 14cm pot. A larger pot does not always mean a larger plant. It is best to increase pot sizes incrementally to avoid shocking the plant, but even so the maidenhair is quite happy to be root bound and will become very large regardless. The only real difference between the two plants is three months of time.
Terracotta pots are perfectly fine to use. The porous nature of unsealed terracotta does wick water out of the soil and tray but as long as the tray is constantly filled there is no difference to the health of the plant. The plant may release spores that can even grow on the outside of this kind of pot!
I have regularly seen maidenhairs happily growing in pots with no drainage holes although I don’t recommend this as the soil can rot and become full of mould and algae (this will kill most plants too.)
Any premium potting mix should be fine to use but always be sure it is high quality. In Australian you’ll most likely be spending about $8-$12 for a bag depending on the size. To guarantee it’s good quality in Australia, keep an eye out for the ‘Australian Standard’ logo. If it doesn’t have this logo it is probably not going to benefit your plants. Make sure the potting mix is stored in the dry space and is fresh (before purchase). Many large chain nurseries will store low quality potting mix in the same space as the premium soils causing contamination of gnat flies and fungus. (We will have a more in depth article on soil soon!)
If you’re reading this article it is highly likely you have killed a maidenhair at least once in your life. Don’t stress as they are easily resurrected by simply trimming off the damaged leaves (even if it is all of them) and then returning to the proper care routine. It may take some time but the new fronds will start to emerge from the roots as long as they are kept moist.
Maidenhair ferns can be propagated via division or from their spores. For higher chances of success and survival always propagate during the warmer months.
Take an established plant and divide the root ball in half by gently ripping or cutting it. Don’t worry if a few leaves die off once the division is complete. Place the new plants into pots and then continue so treat them as usual. A little seaweed extract added at this time can help the plants deal with any shock from being torn in half by YOU! Make sure the new pots you plant into aren’t too large. Choose something bit bigger than the new root ball until the new plant is well adjusted to it’s new life.
Propagation via spores:
Ferns don’t produce a flower or seed, they create spores! We will write a detailed article about the life cycle of ferns at a later date. It is both beautiful and confusing!
Propagation via spores is easy to try! You will know your plant is ready to produce spores when you see the sori (little brown dots on the underside of the leaf tips.) Cut off a few fronds with the sori and place them between two pieces of paper and leave it in a protected space for a week. The spores will drop onto the paper where you can then spread them over the soil in a small pot. Cover the top of the pot with plastic wrap to create a mini greenhouse. Make sure this is not in direct sun as it may get too hot.
Keep the soil moist and after a few weeks you will begin to see the gametophytes emerging. This is just one step in the process to achieving a new plant. After fertilisation of the gametophyte, the sporophytes aka ferns will begin to emerge!
Keep an eye out for our full article on this topic as there is a lot to cover and properly explain.
Common maidenhair fern varieties don’t need any additional humidity. This is hard to believe when you see the thin, feathery leaves but it’s true! There are definitely some species that may be more sensitive, but for the more common ones the natural humidity in Melbourne is perfect. Our average year round relative humidity is 55%. Considering you can find this plant growing in the wild in Victoria it makes sense that it doesn’t need any additional misting or protection.
A regular amount of natural air flow is perfectly fine, whether it’s from an open window or because you keep your plants in a sheltered spot outside. Be careful that heating and cooling is not blowing onto any of your plants though as the air is often very dry and will disturb the natural transpiration processes.
Black tea and tannins:
We’ve seen a lot of posts about watering your maidenhair with cooled off black tea and mixing the spent tea leaves into your soil to add extra tannins to the mix. While I see the logic behind this I haven’t seen any results or well researched articles discussing this. If you know of any resources discussing this topic please send them to us.
Maidenhairs do natural grow along waterways, and in organic matter rich soils which would contain a lot of tannins. I don’t know for sure whether or not additional tannins added to your plant would be beneficial but doing this occasionally certainly won’t have negative effects. The potting mix you use will release tannins as it breaks down. This is what makes the water that drains out of your pots a darker colour.
We don’t use this technique for any of our plants and for now simply recommend using a regular fertilizer and a premium potting mix. Try adding seaweed extracts if you want to take your plant nutrition to the next level!
Mastering the maidenhair is easy and very enjoyable as long as you keep the two most important factors in mind. Bright spot and heaps of water. Once you have the plant in a good position you will find that it flourishes and rapidly grows in size. Due to the speed of growth we recommend buying a smaller (and cheaper) plant and instead spend your money on buying a great pot! If ever you are struggling with a plant it is very helpful to look at the plant’s natural habitat for clues as to what is going wrong. Next time you are walking by one of Melbourne’s waterways be sure to keep an eye out for a maidenhair fern living it up under the shade of a nearby gum tree.