Propagation
Propagating your own ferns is a practical and rewarding way to build your collection, discover unusual and interesting species, and share plants with other enthusiasts. It also plays a valuable role in keeping species and cultivars in cultivation, helping to preserve the diversity of ferns we grow and enjoy.
There are several ways to propagate ferns, depending on the species. Some are very straightforward, while others may take a little experimentation.
Several fern crowns ready for splitting.
A fern crown after splitting and potting.
Propagation by crown division
Some ferns produce new crowns, or offshoots, next to the main plant and gradually form a clump. While this can be attractive in a natural setting, indoors the plant may eventually become large and crowded. Dividing the crowns reduces its size and gives you new plants at the same time.
Most indoor and tropical ferns can be divided at any time of year, although it is best to avoid excessive summer heat or drought and the depths of winter, when growth may be slow.
Sometimes a crown can simply be prised away with a trowel. More often, you will need to remove the clump from the ground or its pot and carefully prise the crowns apart by hand. A large knife may occasionally be needed. Make sure each crown retains some roots and avoid damaging the crown itself.
Pot each division separately and keep it in conditions similar to the parent plant. As the plants will have lost some roots, keep the compost consistently moist, but not wet, while new roots develop. This will also reduce the risk of rot.
Once you see new growth, the plants can be moved to their intended growing positions.
A Woodwardia terminal bulbil.
Propagation from bulbils and plantlets
Some ferns make propagation particularly easy by producing bulbils or plantlets on their fronds. These may drop off and root where conditions are suitable, or reach the ground as the parent frond collapses and dies.
Some ‘walking ferns’ produce a plantlet at the tip of a frond. Pin the plantlet onto compost in a pot next to the parent plant and, once it is growing well, separate it from the original fern.
Bulbils and plantlets growing on the surface of fronds can also be removed and placed on sterile compost in a sealed container. Keep them damp and pest-free while they develop roots and their own fronds. This may take several months.
Once established, separate the new plant from any remains of the original frond to help avoid rot.
Plantlets on the surface of a Woodwardia frond.
Davallia rhizomes.
A separated section of Davallia rhizome rooting and showing new growth.
Propagation from stolons and rhizomes
Many tropical ferns are epiphytes, growing on rocks and trees in habitats that are continuously damp or regularly wetted by storms. They often have creeping rhizomes that produce roots to anchor the plant and absorb water and nutrients.
These roots generally develop towards the growing tip, ahead of the new fronds, so a rhizome may extend for many centimetres without producing fronds.
The most reliable way to propagate these ferns is to pin the growing rhizome onto suitable compost while it is still attached to the parent plant. A pot alongside the original plant works well. Once new fronds emerge, roots are likely to have formed underneath and the rhizome can be cut to separate the new plant.
After separation, keep the new plant in a sealed container or plastic bag if necessary to reduce water loss from the fronds. Once you see active growth, it can be gradually hardened off.
If you have a section of rhizome without roots but with fronds, lay it on sterile, damp compost or sphagnum moss in a closed container. Keep it somewhere bright but out of direct light. Roots may develop over the next few months. Active growth at the tip is a sign that the plant can be gradually hardened off before being removed and potted up.
Terrestrial ferns with creeping rhizomes are simpler. Separate a piece of rooted rhizome from the parent plant, pot it into damp compost and keep it in a plastic bag or container until you see new growth.
Stolons are aerial rhizomes most commonly seen in Nephrolepis and some Goniophlebium species. They can grow up to a metre long and have a small growing tip. Allow the tip to touch damp compost while it remains attached to the parent plant; detached pieces of stolon will not grow.
Propagation from spores
Most ferns reproduce from spores, and growing them this way is a fascinating way to produce new plants. The process involves collecting ripe spores, sowing them onto sterile compost and caring for the developing plants through the different stages of growth.
It takes patience, but it can be very rewarding. Find out how to collect, sow and grow ferns from spores in our step-by-step guide.