Growing Ferns From Spore
Nothing for the impatient!
1. Get some spores from a fertile frond. To decide if the sporangia (spore capsules) are mature watch them: if they appear firm and compact, it's too early. If they appear blurry, it might be too late. If your plant stands on a table and you notice dust-like granules around the pot then at least one frond is releasing its spores.
2. If you don't want to cut the frond you may tip it gently while holding a sheet of paper underneath the frond. Put the collected spores into an envelope if you don't want to sow them immediately.
3. Now you need some potting mix, douse it with boiling water (or put it into a microwave oven) to kill mold, insects and the seeds of other plants and put it into a plastic container. Drill some holes into the container's bottom.
4. Pick up the spores with a knife and tap it gently all over the soil. Another good practice is to add the spore to a small amount of water in a spray bottle and to spray this on to the mix.
5. Cover the container with plastic wrap (or something transparent that won't let air through it and place it in a dry, warm, well-lit place out of direct sunlight. Put it into a flat pod and fill that pod with water. It will flow through the container's holes and keep the soil wet.
6. Now wait for some weeks to some months. The first growth will result in a small salad of miniature plants, the Prothalli. If you provide enough humidity the sperm are able to swim to the egg thus producing the sporeling, the second growth (see Fern FAQ).
7. When the sporelings are recognizable as small ferns (they will be 5mm to 2cm tall) you may gently remove them out of their soil and place them into their next growing medium. You should keep them under controlled conditions and harden them off slowly. Don't be impatient, this will take some time.