Growing Ferns from Spores

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A photo from a private event at my home in February 2015 with featured speaker Richie Steffen, co-author along with Sue Olsen of The Plant Lover’s Guide to Ferns (The Plant Lover’s Guides). The presentation was ALL about ferns and it was after that talk I took the spore plunge. I’ve been quietly sporing ever since.

My first gardening job as a kid was to cut back Mom’s sword ferns each year. She had roughly 100+ of them. It was a lot of work but it ended up looking quite lovely once they’d all reemerged again. I never thought about how they were propagated though. They were just there with all of the other native plants. I took them for granted.

When Richie Steffen came to my house to give a talk to the underground Daisy Chain group, he really made me think about the wonders of hybridization. Many fern hybrids created during the Victorian era are long gone now. There are so many possibilities it seemed endless after this event so I decided to collect some spores at Cistus Nursery to see what I could come up with on my own.

My first crop of ferns at Cistus Nursery. This is Pyrossia lingua ‘Nokogiri Ba’ which came true from spore. Who woulda thunk it? You don’t know until you try it.

Several crops came up, and as they did so I observed them carefully. Sporing requires keen patience and some requisite knowledge as well as an understanding of how to coax fern babies along. After my first successful crops though, I’ve kept at it, and have tried a variety of different things. Each year I experiment with new plants to keep my skills sharp. This process takes a lot of time. At certain points it can feel frustrating, and you might want to just throw your arms up in the air and chuck the container. It’s easy to get the sporelings going, but growing them on has been the greatest challenge for me. You can ignore them initially, but you must keep an eye on them to make sure they don’t die out on you.

Clean containers are a requirement. I personally have fallen in love with the takeout containers of the pandemic. Many restaurants use ones now that are microwave and dishwasher safe. Whenever I can save time by sanitizing in the dishwasher, I’m a happy propagatrix.

As for a soilless medium, I tend to use whatever I have on hand. To be honest, you should sterilize it as well, but I often forget. You can do so in a microwave or oven.

Using a container with a tight lid is also important. You want the spores to be in a very humid environment and you do not want to open the lid frequently since it’s more like a Petri dish and can be contaminated far more easily than other seed trays. This can lead to sudden death so be cautious about sanitizing the area where you’re working.

Since I work with a nurseryman who also collects in the wild, I can collect at the nursery, and after Sean has collected elsewhere, I can prepare the spores after the fronds have been placed between sheets of paper.

(*I do NOT recommend that amateur growers collect in the wild. This honestly requires a license typically and we do this to keep plants in the trade to HELP prevent the poaching of entire plants. If you’re interested in purchasing spores, keep reading. I will get to that below.)

At the nursery, I collect spores as they ripen. Most ferns we grow though are primarily divided since it’s quick and easy, but not all ferns grow quickly.

When you collect in the wild—or even from the garden of a friend—you have to do what you can with what you have at the moment you encounter it. This might mean sowing them immediately, or you may have to press fronds by keeping them warm and dry for a few weeks more in a warm and dry basement.

I can’t say at this point that this part is an easy process. It takes observation and experience to understand when a fern is ready. I’ve collected many myself that ended up being duds. I have also collected from one fern only to have spores from another more weedy one appear. (Spores do float around on the breeze so it makes sense that there would be contamination.) It is not easy to isolate most ferns so you really have to simply wing it and try not to be disappointed if it’s not quite as exciting as you’d wanted it to be when you began.

Once I sow the spores on the surface of the medium I use a water bottle to spray them into the soil. (By the way, the medium is also moistened before I sow the spores.) After that, I slap the lid back on tightly and I wait. I usually leave them in a cool spot for a few weeks with a bit of light. You can stack them in a window and forget them too. It’s oddly that easy but it requires that leap of faith!

In the photos above, the two in the middle show what can happen when your soilless mixture has sphagnum in it. This is not a bad thing to have happen, but to a beginner, it might be frustrating and a bit confusing. Luckily ferns and sphagnum can coexist well together.

Additionally, notice how the gametophytes in the second photo look like liverwort. Folks might be confused by this I’m sure and at this stage the containers might be tossed hastily. But guess what? Before the sporophytes appear, you will have gametophytes. Be patient. Be observant. If you know liverwort, you’ll know it when it hits its next growth stage. Soon you will see antheridial and/or archegonium heads. At that point, you can prick that stuff out, but you need to wait.

If your ferns are to grow successfully, soon you’ll see those little tiny sporophytes. (They’re visible in the 3 photos above and to the right, but they may be difficult to see. The photo with the sphagnum has another kind of Pyrossia, and the photo on the far right is a tree fern.)

These are plugs I spored with spores from the American Fern Society. While many were very successful, I had a lot of spores that spread around, so pricking them out was a bit messier then expected. This Bio Dome system from Park Seed typically works well for me too when I have fewer spores to sow. Since it floats on water it is evenly bottom watered which allows me to spore them and forget.

Lastly, I want to help you to purchase spores by encouraging you to join fern organizations. I usually purchase from the Hardy Fern Foundation and the American Fern Society but remember that you MUST become a member in order to purchase from these groups. Individual collectors, independent growers, public gardens, and others donate their own time to collect and send in these spores and volunteers help to run these spore exchanges. Both are an incredible resource to us all, and we should support them as much as is possible.

I hope that this has helped a little bit. I skimmed over a lot of information but I know it’s available elsewhere and has been provided free online by expert growers if you search around. I’m just a propagator with knowledge acquired over years of practice at my craft at home and in the professional arena.

For a much more thorough description of all of this I recommend this article provided online from the Brooklyn Botanic Garden by Judith Jones of Fancy Fronds Nursery.

Thanks everyone for reading this and if you have any questions, please ask away in the comments section.

18 thoughts on “Growing Ferns from Spores”

  1. Have always been intrigued by seed sowing but found spore sowing intimidating. Always sounded like some complicated lab experiment. Your description has motivated me to try some of my native ferns. Something new and fun. Thanks

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  2. So your pyrrosia baby that I bought at Cistus, that’s the Pyrossia lingua ‘Nokogiri Ba’? I was looking for a label the other day and couldn’t find it. Also… you’ve inspired me. I have great ferns and I would like more of them, plus I too have take out containers that I would love to use! Maybe with a little success I’ll even order spore from the HFF (I am a member). You should hold a workshop in your garden, I’m sure many of us would love to learn more in person!

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    • I am often surprised that Evan and I are not asked to give propagation workshops. Might be a lot of fun to do at home too. Go for the fern prop project too. It might fail and become an ugly science project but it very well may succeed and yup! That is the correct Pyrossia! Can’t recall what the new one is coming up at home but it is one I ordered.

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  3. Noah Oldham

    Do you cater your substrate to the varieties or do you find that the gametophyte stage is pretty versatile but the sporophytes are more tricky? I ask because I want to start experimenting with more tropical species (like the elaphoglossums and others) but I wonder if it takes a different substrate or set of conditions. I’ve wondered the same thing with dry land ferns (cheilanthes, pellaea and other tricky genera.

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    • I think that for the initial germination the substrate being the same is ok. As for the sporophyte phase, it’s likely that the tropical species could benefit from some different additions, but I think I would base those mostly on how and where the grow, for instance, terrestrial versus epiphytic. My gut says that it’s likely not nearly as important as temperature though. Temperature seems to be key for small plant babies due to dampening off and pests etc. Add to this requisite humidity too and it’s kind of a bit complicated but that just sounds like a lot of fun to me! I’ve killed some tropical babies already but am up for the tackling the challenge again in the future!

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      • I mostly have grown temperate ferns. I keep them all in heated areas. As work some of them have rotted out so it should be at least around 65F. I think with the tropicals I would say the same but I would look at them all on a case-by-case basis and guess based on their native growing environment to see what the temp ranges are like.

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  4. Noah Oldham

    Also…have you ever found a list of germination times by genera? Some things seem to take fooooooorever to germinate (like blechnum) but I can never find any good resources on germination rates or time for hobbies growers. I don’t have space to keep things around for months but I would if I thought they’d germinate.
    It seems in general like there are tons of simple how to guides, and tons of doctoral level research papers but not so much in the middle for us amateurs.

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    • I don’t think there can be a set list due to many factors. The first hangup I think of is the age of the spores and how they’ve been stored. I guess you could have averages. In general, I think most ferns are just slow. I tend to keep them around for months too but I keep making more space lol. I am so glad my husband hasn’t lost his mind over both the basement AND the garage turning into my plant space.

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  5. One of my memories of my grandmother is her showing me the spores on the undersides of her ferns, and then seeing her grow them from spores in her greenhouse. She didn’t have a huge collection; she wouldn’t have had the financial wherewithal, or the ability to travel to collect. I also remember she had lots of ferns in a narrow shady walk between her and her neighbor’s house. She had a feud going on with her neighbor and would get furious when he would put his ladder on her ferns to wash his windows. He called them, in a Norwegian accent, “Those damn weeds.” Another childhood memory is a girl who seemed so much older and more sophisticated (she was probably eight years old) showing me how to draw ferns with my crayons.

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  7. Craig

    My parents’ house had a fern bed in the patio area filled with Athyrium lady ferns and Woodwardia western chain ferns. My self appointed job was cleaning them up right before they started growing each year. The plants stayed strong and healthy for more than thirty years and eventually became tree fernesque by growing short trunks.

    My first job in horticulture was working in an old time nursery that used sand covered benches – low bench tops had raised edges then a plastic sheet was placed inside and filled with a couple of inches of sand. Deep propagating trays could be turned upside down and placed on top of the sand to keep pots and plants clean if desired and I regularly grew plants on top of them. The trays didn’t fit the benches perfectly so there was usually a small amount of space left on the far side away from the aisles. The greenhouse was set up for growing african violets so it was kept 68-72° day and night and was usually shaded and humid. Perfect for the violets but tropical ferns liked it too. I encouraged pteris, polypodium, and adiantum ferns to grow. It was a lot of fun seeing the spores germinating and the gametophytes grow and then the first fronds. I would flood the gametophytes with water if the fronds seemed to be taking too long to start growing. The ferns and a few other plants that I also encouraged growing on the sand were considered weeds so I would need to purge everything a few times a year but with so many ferns around there were always plenty of spores to start the next generation. Good times.

    In almost every greenhouse I’ve visited I have usually found oddball plants tucked away in spare corners and “empty” spots. I’ve always thought of them as Greenhouse Pets as that’s how I’ve thought of my little ferns. They aren’t easy to grow without a setup to provide for their needs so I didn’t try growing them after I left the world of greenhouse growing. But I’ve never forgotten them and the pleasure they gave me so I’ve been gathering them again whenever I can find them and it’s nice getting reacquainted with my old friends.

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  8. Where I fail is growing them on. I had a petri plate filled with cute little gametophytes of a desert fern from New Mexico that lasted from 2012-2018. I just never potted them up to the next size. Then, one day, I noticed they had dried out and they never recovered. Oh well. I’m trying again anyway.

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