I have had the purple-stemmed Osmunda, r. purpurascens, growing in a pot for around three years now. It does need plenty of moisture so I keep a saucer underneath it all the time to retain water. It does reasonably well and grows up to about 2 foot or so high by 4 foot wide in the summer. I assume it would get rather larger in open ground.

I intend to re-pot it as soon as weather conditions permit. You can come and see it if you like although Osmundas don't look much a this yime of year!

Anyway, I'm not sure these "flowers" - I mean these fertile fronds - only depend on the growing conditions, I would be inclined to think it's also a question of age/maturity of the plant.

As for its watering needs, it certainly enjoys a moist (but not water-logged) soil during the growing season but, in my experience, does also well in a very good garden soil whith plenty of humus (leaf mould is the best). In the wild, it's a bank plant, not an aquatic plant, which means the water runs down, its roots don't sit in water.

I grow half a dozen of them and the oldest one (picture here and here with Cornus 'Norman Hadden' in the background) is about 8 years old. It grows in full sun (but they do like a bit of shade) in an acidic, moist and plenty of humus, rich garden soil.

They can become quite big indeed, old specimens can reach more than 2m (that would be 6.5 feet) high and wide, but that's in the wild or with very good growing conditions... and time. They take time to settle/establish, can make huge rootballs that are not so easy to transplant and, in my humble opinion, will always do better in the ground than in a pot - even a very large one.

If you can dig a big hole, amend it with leaf mould, replant it, mulch again with leaves, water it for the first couple of years, mulch with more leaf mould each spring and give it time (plenty of time), I think it's worth it. It's such a magnificent plant.

Olivier.

"Flourish: to grow well or luxuriantly; thrive"

Olivier.

Robby Em, your Osmunda sounds about the right size for my garden. If it reaches 6' there wouldn't be much room left for anything else! I'd love to come and see it when it gets round to doing anything.

I think I'll be hedging my bets with some kind of pot, saves making a proper decision for another year.

It's a deal, once the weather warms up a bit!
I've been to Palmer's at Enderby today to get a larger pot for replanting purposes.

Robby.

GN/Heather.

Yes I agree, not cheap at Palmer's but the coffee's nice! And there's things to see and do undercover if you have non-gardeners in the party.

Thanks a lot for the plants offer, I've never even heard of some of those you mention. I'll be in touch shortly. I've quite a few grasses available if you want to do 'swapsies': Milium effusum Aureum and Stipa arundinacea for starters, and a few ferns.

I saw some Osmunda in the wild a few years ago, at Askham Bog SSSI, near York. A remarkable sight was the huge mounds of fibre they are apt to produce, consisting of ariel rhizoids presumably adapted to help the plant's aeration in its boggy environment. They were not growing on a water's edge but in marsh. It is the Osmunda's fibre which was its undoing for wild populations at the turn of the 20th century when it was much in demand as a growing medium for orchids, right until the 1970s (when most of it was imported from Italy). Many orchid growers still swear by it, but then they are the sort of growers who think nothing of importing wild specimens and cannot appreciate that epiphytic orchids will grow in anything as long as their watering needs are properly attended to (there, I'll get off my soapbox now).