How to Propagate Garden Ferns and Grow Your Own Cheap Plants

The first fronds (leaves) of garden ferns to appear in spring are purely vegetative, but those which unfurl later have sporangia or spore capsules. These sporangia form on the underside of the frond. They are pale to begin with then turn darker as the spores (dust-like cells) mature within them.

How Ferns Reproduce in Nature

As the sporangium matures and dries out it rips wide apart. Spores, often thousands of them, are forcefully flung out. Those which land on a suitably damp surface germinate and develop into a tiny heart-shaped pad of delicate green tissue called a prothallus which enlarges before the first fronds of the new ferns appear.

Where the Gardener Can Get Fern Spores

Pieces of spore-bearing frond can be collected from mature ferns in mid to late summer before the sporangia explode. If these are put in a dry paper bag for a day or two the spores will be ejected and settle in the bottom of the bag. Alternatively spores can be bought from the British Pteridological Society.

How to Propagate Ferns From Spores

For the gardener spore propagation is relatively simple provided strict hygiene is adhered to:-

• Spores are sown in small clean plastic pots 9 x 9cm which have been soaked in domestic disinfectant for thirty minutes before filling just to the brim with seed compost.
• The surface of the compost must be sterilized and the recommended method is to cut a disc of kitchen roll or newspaper to fit snugly in the top of the pot. Boiling water is then poured slowly through the disc until the water coming out of the bottom of the pot is very hot.
• The surface of the pot is then covered with glass or plastic until the compost is cold.
• Then the spores are spread thinly on the surface of the compost.
• The pot is then enclosed inside a clean polythene bag which is tied at the top so creating a miniature greenhouse.
• The pot is then placed on a windowsill, but not one in direct sunlight.

Germination of Fern Spores

The next stage in the propagation of garden ferns by spores requires patience. Wait a month or two and if the process has been successful a light green film of tiny prothalli will appear on the surface of the compost. The tiny little plants or sporelings as they are called can be pricked out into pots of sterilized compost the following spring.

Fern Propagation May be Unpredictable

As very few ferns breed true the results of all this meticulous attention to hygiene and patience may be unpredictable. Whatever they are like, and many may be extremely garden worthy, these young ferns won’t be ready to plant in the garden for at least another year. That may seem a long time in human terms, but it is less than a split second in the long history of these ancient plants.