Polygonatum stenanthum - update for Ben and Chad perhaps?

[JohnH]

Unfortunately, I don't have the skills or conditions to grow any of the more spectacular obscure species, and the only Polygonatum I have in flower at the moment is kingianum.... but it doesn't look like any photos I see online.
The nearest match I can find was John Jearrard's plant. The picture on his site was taken some time ago and it seems he wasn't sure it was the real thing. I wonder if he came to any conclusions, or if anyone can help with a positive id?



I have a few different verticillatum that have only just emerged, and one surviving 'Betberg' that is only 20cms tall when fully grown for me. Not sure why 'Betberg' is remaining so tiny, the leaves are normal size and purple as they emerge, but the stems are short. Is there a dwarf version?

[MartinNicklin]

So the shoot in my original photo which filled me with hope fizzled away but it sent up another. Here are some photos which might help with the definitive ID. Dog included for scale.









It’s lovely but would be much more lovely and impressive on the eye if it ever forms a clump due to its impressive height and the noticeably larger flowers. Do you think it needs a bigger pot? I understand they don’t like being crowded out in the garden so because my borders are so packed, it will have to remain in a pot where I can at least keep checks on it.

[Chad]

Wow!

That falls within what I understand to be Polygonatum macranthum.

I may be wrong.

Yes it would enjoy a much bigger pot.

Keep it well fed and watered this year and when dormant repot it into fresh compost in a 20L pot and it should be even happier.

As always, the growth you see depends on how happy it was the year before, so don't expect to see huge benefits from repotting until the second year.

I have Polygonatum vietnamicum in a 70L tub and it only gets to half the height of those in the ground. I'm feeding it well this year and will see if that gets it bigger next year.

Chad

[BenC]

Hi Martin, that's a fantastic plant. I would also agree on it being P.macranthum based on the flower size and leaf arrangement. Chad's advice is spot on - pot up into a bigger pot, and hope that it produces more underground growth and hence more stems next season.

And John - sorry I missed your questions. I can't help on your 'kingianum' I'm afraid. I am not aware of a dwarf 'Betberg'. It should get to around a couple of feet tall after a few years in the ground. Maybe some feed / generous mulch and a bit of additional watering might help it along?

[MartinNicklin]

Ben and Chad thank you both for this more definitive ID. I will indeed put it into a bigger pot at the end of the season and look after it. A clump would look lovely so that’s my ambition! Next update in 2050!

[JohnH]

That is a very nice plant Martin, the flowers are amazing.

Thank you Ben, I am not the most patient of gardeners and I would guess 'Betberg' is now probably twice the size it was last year, the recent rains have certainly helped. It is a really good plant, but I find the dusky purple shade of the emerging leaves disappears very quickly. I shouldn't say this too loudly but, as far as I can tell, the local sawfly haven't tracked it down....... yet.

[MartinNicklin]

I posted this lovely plant on the Unusual Plants FB page. I had a response from Bleddyn Wynn-Jones who said it was shown on the Crûg stand at Chelsea in 2011, when I saw it and then wanted one. It was displayed as stenanthum and then, as you Chad and Ben correctly state, it was changed to macranthum.

[Chad]

Martin,

Is it really overtopping a garden wall, 2M?

If so huge respect for having got it that much bigger.

I understand it is a monopodial species, so the rhizome seldom branches.

If you want a pot full of stems you'll need to grow a batch from seed [get busy with a paint brush now], or be very brave and cut the rhizome once it has died down in the autumn.

I don't know how successful the latter approach is, and it does look a bit risky.

John,

I now have a dwarf 'Betberg' as well.

It didn't use to be.

I think mine needs repotting and feeding.

Chad

[MartinNicklin]

I’d love to bask in the glory of being able to claim it was that tall Chad! It’s on a small table. I’d say it’s about 4ft. I’ll have a go at pollination but Bleddyn said it took 16 years to get something like the Chelsea pot! I did repot it last year and it does seem to be a thicker stem but I can’t see myself ever achieving the look I’d hoped for.

Have you got Night Lark amongst your collection and if so, can you see any difference to Night Heron?

[Chad]

Subtle genus jump there Martin to Disporum longistylum forms.

I only have a seedling of 'Night Heron' that isn't quite as good as the 'true' plant.

I understand from commercial growers that seedlings are all close to the parent, but with a keen eye outliers can be selected. 

Paul at Edulis picked out 'Night Lark' as being taller, and Nick at PanGlobal picked out ‘Bagheera’ as a darker plant.

So many of 'Night Heron' that were sold were actually seedlings rather than divisions that I'm not sure what the original plant was. That's assuming 'Night Heron' was a clonal plant and not a seed batch in the first place. 

Mine would be a better plant if it was planted out and fed.

I have it berrying now. As with so many things, if I got myself organised I could raise a thousand seedlings and pick out a darker one.

I could do the same with Polygonatum × hybridum 'Betberg', but that hasn't set berries this year.  Does it ever?

Chad