Plant Guide: Ferns
Ferns are a gorgeous plant to have in the garden. Their arching fronds, tiny delicate leaflets and rich green colour help to create a verdant and lush vibe wherever they’re planted. Typically thriving in shaded and damp locations, they’re perfect for spots with low light. We love to use them growing out of stone walls, in damp corners or as underplanting for taller trees and shrubs.
There are a huge variety of different ferns available, so you can find the perfect one to match most spots.
Plant type:
Ferns can be evergreen or deciduous, the former keeping their leaves throughout the winter months, and the latter dying back beneath the ground during this time.
How to plant:
Most ferns are grown in containers and can be planted out in the garden throughout the year, as long as the ground isn’t frozen. See our guide to planting out container grown plants for more info. They tend to establish best in planted in Autumn – as there is usually plenty of rain to keep them well-watered – but if planting at any other time of year, just take care to water well while they get established.
Growing conditions:
Ferns are well known for loving damp and shady conditions and on the whole this is the best spot for them, though there are some varieties that can cope with sunnier or drier locations.
From tiny ferns that can root into the smallest rocky outcrop on a wall (such as Asplenium trichomanes), to huge ferns with vast unfurling fronds that need plenty of boggy soil to grow in (Osmunda regalis, the royal fern, is one of the biggest ferns in Europe) there are ferns that do well in almost every sized space available! If you’ve got a particular shaded spot to fill, a bit of research should find you the perfect plant.
Grow with:
Just about anything! Ferns tend to pair well with all sorts of plants. Mixed with flowering plants, the delicate fern leaves set off blooms. We love to use ferns with geraniums and erigeron karvinskianus, both of which have smallish flower heads that appear to float from among the fern leaves. Or match the feathery fern foliage with some green leaves of contrasting shapes: hostas, brunnera, and Asarum europaeum all look great alongside ferns. Just take care to choose plants with similar growing conditions.
Care:
The majority of ferns need consistent moisture to grow well, so will tend to need watering in any especially dry periods. Other than this, ferns are usually fairly low-maintenance and don’t need much ongoing care.
Evergreen ferns that keep their fronds over the winter months might start to look a bit straggly in the Spring time, so give them a prune in late Winter if so, just before the fresh fronds start to appear.
Favourite ferns:
We have so many favourite varieties of fern, we’ve made a whole list of them! Check out our ten favourite ferns.
Polystichum setiferum
Tree ferns in a garden
Evergreen ferns growing in a wall
How to propagate:
Spore propagation is a somewhat complicated and lengthy way of propagating ferns, but is also very fun and can lead to lots of new plants! Ferns don’t reproduce with seeds, but instead with spores, which grow on the underside of the leaves. The spores show up as small dark brown lines or spots, along the underside of the leaves. Check the plant in Summer for spores, they will start off looking pale green, but turn to deep brown when ripe. Cut one leaf from the plant when the spores are ripe. Place the leaves upside down on a piece of dry paper in a warm, dark place (a shed in the summer months is perfect for this). After a few days, the spores will have fallen from the fronds, creating what almost looks like a print of the leaves on the paper. Prepare a tray filled with sterilised compost, by pouring boiling water over it and waiting for it to cool down completely. It’s important to do this to kill off any dormant weed seeds that might be in the compost. Shake the paper over a seed tray, to distribute the spores thinly on the surface of the compost. Cover the tray either with a see-through plastic bag or a layer of cling film. (We have also improvised before, and used lidded takeaway containers, with a few small drainage holes poked into the bottom, which has worked perfectly as a recycled, covered tray!) Sealing the tray is crucial, though, to maintain the moisture levels that the spores need to stay alive, and to keep any external elements out. Label the tray, and leave it in a cool, shady spot for a few months.
After a few months, a thin green layer will grow over the top of the compost, similar in appearance to liverwort. This is the intermediate stage between spores and ferns. A month or so after this, small tiny fronds will appear – these are the beginnings of the new ferns. Once large enough, each new plant can be potted on. Keep it growing under plastic for a while, to maintain the humidity that is crucial for its survival as a small plant. A sowing in the Summer months should have new baby plants by the Winter. But the plants should be grown on inside in ideal conditions (humid and shaded) for at least a year or two, before being planted in the garden. So, all in all, this is an extensive process for new plants, but can, at the very least, be an enjoyable challenge!
Quicker, and generally more reliable, many ferns can also be propagated with division. Dig the plant up carefully from the soil, and cut into two or more sections. One can be replanted in the original position, and the other(s) moved to a new spot. For more on division, see our guide.
If ferns are happy in a garden, they often tend to spread, either by natural spore spreading, or some will grow plantlets from runners. You can easily dig up this baby plants, when you spot them, and place them in your desired position.
