A beginner’s experience of growing Pyrrosia

I first came across Pyrrosia about four years ago, on a summer holiday in Cornwall. Soon after this, I met someone, now a good friend, who has a vast collection of the genus. Seeing his plants really added to my appreciation of these ferns. I also remember reading about Pyrrosia in a book written by Martin Rickard; I loved the pictures of them in his book: the grey-green colouring of the frond with the rusty-brown backing. They looked very attractive. So whereas many of our IATFG group members may well have been growing these plants for many years, my experience of growing Pyrrosia is limited to just the last few years.

I quickly found out that they were not particularly easy to source. Very few nurseries have them available to purchase and then only occasionally. However, many individuals have been overly generous and shared rhizomes or small divisions with me. I have carefully tended to these, growing them on, and now have quite a collection which I’m trying to keep happy in my garden in South London.

Generally speaking, I have a habit of overwatering. I’m more likely to kill a plant through giving it too much water than under watering it. Many Pyrrosia grow on trees or rocks in the wild. They don’t require much watering. With this in mind, I generally plant my Pyrrosia straight into terracotta pots, which dry out quicker than plastic pots. I also try to use a very free-draining substrate mix. Some people are quite accurate and consistent with their potting mixes, however, to be honest, mine tend to vary. I usually plant Pyrrosia straight into Melcourt Composted Fine Bark™. Sometimes I plant in a special Melcourt mix for permanent planters, which is quite similar to the first but with more finer bark and the addition of loam and sand. At other times I mix my own using peat, grit and mini-chipped bark. In my experience I think almost any mix will work,

as long as it drains well, preventing the plant from sitting in wet soil for long periods.

One of the issues with using bark as a substrate is lack of nutrients. When comparing my plants to a friends plants, his seem to grow a bit faster in his slightly more fertile mix. However, I will stick with mine, for the time being, simply because I know it dries out quickly and I am less likely to kill them due to overwatering. I do feed my ferns about once a month from April until September, using a liquid seaweed feed. One thing I learnt quite quickly was that Pyrrosia do not appreciate the sun during South London summers. Summer days can be hot and damaging in this part of the country. I’ve had a few issues with plants positioned in sunny spots, even if it’s only 2–3 hours of sunshine in a day. In my experience, Pyrrosia do not like strong sun. I’ve had one or two totally shrivel up and look horrendous. Thankfully they recovered. I’ve also had a few damaged around the edges of the fronds from sun scorching. I now grow them in full shade throughout the day and I am having much better results. The plants grow with larger and lusher fronds. I’ve seen Pyrrosia come from sunny spots in nurseries and be positioned in full shade in my garden and be transformed in appearance within a year. They really can look fantastic given the right growing conditions!

As I mentioned before, many people have kindly given me rhizomes of different Pyrrosia. These rhizomes usually have next to no roots. Of course, it’s great to get a division with some roots, however, unrooted rhizomes can get going quickly. People do

this differently, but I usually just peg down the rhizomes with some metal wire onto my mix of composted chipped bark. I sprinkle a bit of the composted bark mix over the top once pegged down. I usually end up having some of the rhizomes covered with mix but also having some bits of rhizome still showing. At the beginning of this process it can be quite easy to kill these rhizomes by overwatering. So I aim to keep them slightly drier than my fully rooted ferns. I do get quite good success with these rhizomes, and usually within a year I have a plant which is growing new fronds. It’s great to be able to grow new Pyrrosia in this way and it makes expanding the collection much easier.

I soon realised that there were a number of Pyrrosia which I wanted to grow which required warmer conditions. Plants like P. abbreviata, P. angustata, P. glabra (syn. P. nuda) and P. lanceolata to name a few. I don’t mean warmer summer conditions, but warmer conditions over winter. So last winter I turned the heating up a bit in my greenhouse and kept it to a minimum of 12 °C. I did my best to keep the humidity up, and water appropriately and it seemed to work. The more tropical Pyrrosia survived and thrived. I had an issue with spider mite though, a big learning curve for me, it did a lot of damage in the greenhouse! I now aim to keep humidity higher, which I’ve heard should help. I will also try a biological pest control method, which a friend of mine has used successfully in his greenhouses.

I’ve managed to import a few more tropical ferns this year to add to the greenhouse. Some from Siamgreenculture and others from Christian Klein. Most of these are showing signs of new growth already. Christian Klein grows his ferns in soil but are shipped as bare rhizomes due to plant shipping regulations. Siamgreenculture grow a lot of their ferns now in ‘non-soil media’. Their ‘non-soil media’ looks interesting: some sort of gritty mix with something looking like polystyrene added. This means the

‘soil’ can be removed easily for shipping and the plants generally come with some viable roots attached to the rhizomes.

Last winter, a cold one in South London, I kept a number of hardier Pyrrosia outside all winter. However, some of these did not look amazing come the spring. So this year I will aim to keep more frost free simply to maintain better looking plants. I’ll probably keep them around 3 °C in a small greenhouse. Having said this, I’ve also planted a few out around the garden and plan on planting more out over the next year or so. So far I’ve planted out P. similis, P. drakeana and P. sheareri. I also have P. porosa, in a pot attached to the house which sailed through last winter untouched. As some of the others mature and grow in size, I will divide bits off and plant out pieces to test their hardiness.

One other thing that I love about Pyrrosia is that there seem to be different forms and clones in circulation, not only in the UK but also in Europe and further afield. This adds more excitement to collecting them! I look forward to finding more Pyrrosia in the future and expanding my collection.

EVAN SHARP

Evan grows a number of ferns in his small South London garden. With a love for woodland plants, particularly Araliaceae, and other evergreens from around the world. He is a gardener by trade and works in the London area. Favoured ferns include Pyrrosia, Lepisorus and Microsorum.