Ferns grown from spores are thriving in the McAlpin Farm greenhouses. The process of growing ferns for our lands and gardens from spores is a slow one that starts in the fall and, if successful, gives us a finished plant in July. I have been working on perfecting this process over the past few winters.
1. I start with these take-out containers. You can use anything comparable, but I like these because they have the lids that fit tight, keeping the moisture in and have a clear lid to allow light in. I bought ours locally, at Renys. We clean and sanitize our containers before using them.
2. I use a fine peat and perlite soilless potting mix from Lambert, sold as a germinating mix. I bought ours from Griffins. The soil is sterilized in the microwave for three to five minutes and after it is cooled, we fill the containers three quarters of the way with the moistened mix and lightly compact it.
3. The soil surface is moistened again and then I scatter the dust-sized spores on the surface of the soil. The fern spores are purchased from the American Fern Society, Hardy Fern Foundation, and North American Rock Garden Society. I have also collected spores from ferns growing locally. The lids are put on and the containers are placed in a partially sunny location where is stays roughly 70 degrees. The water droplets inside the lid are great to see, this shows that there is high humidity which is important for spore germination.
4. In three months, the spores germinate into this young fern stage. At this stage I transplant them into cell flats.
5. This clump of young ferns is placed on the soil surface (using same soil mix as above) at the same depth as it was in its germinating container.
6. The young fern clumps are centered in the cell flat. This is what they look like one week after transplanting.
7. They are covered with a plastic dome that fits over the entire flat (purchased at Johnny’s Seeds) then placed back in a warm room with partial sun. They are checked for moisture daily and misted as needed because they can die quickly if they dry out at any stage of growing.
8. At three weeks from transplanting, I am starting to see the true leaves of the maidenhair fern starting to appear. This is one of the 30 different fern species I am growing this year. Once the ferns are fully rooted in this cell flat they will be transplanted into their final pot and be available for planting this summer in our lands and gardens.
Jon Knight, McAlpin Farm & Abby Garden Manager