Problems with yellow-flowered Pulsatillas

[Maggi Young]

 A question for the forumists .....

"I have every year problems with growing yellow Pulsatillas (P. aurea and P.alpina sulphurea) from seed. After a good germination the seed-leaves turn to brown and fade away after some weeks. Could you give me an advice how to prevent this and to get healthy yellow Pulsatillas?

Many thanks!

Best wishes

Hans D.
Germany "

[Lesley Cox]

I have never had seed of P. aurea but regularly try P. alpina sulphurea (P.a.apiifolia?) And for me too, there is quite good germination then the leaves brown off but it seems that's just what they do. I see nothing more, but if left alone in the seed pot, a new little growth appears in the coming spring and away they go. Yes, I lose some but always a few survive. But I've had no flowers yet after several years.

[Gabriela]

Same for me happening right now with Pulsatilla aurea. My worry is that they remain green for a very short time and I can't imagine having time to build up reserves for next year growth. Very upsetting.

[Philippe]

Same for me. The young leaves/cotyledons of seedlings generally turn rapidly brown the first summer, letting the pot soon empty for most of the growing season then.
It seems these plants first build up roots in earlier life stages, rather than leaves ( as does sometimes Anemone narcissiflora and other Ranunculaceae relatives too)

[Darren]

Likewise. I have not tried aurea but alpina apiifolia germinates OK and then the cotyledons start dying back after a few weeks but this is usually accompanied by a first true leaf emerging slightly to one side of the cotyledons. As noted by Philippe above, sometimes this waits until the following season - I wonder if climate or sowing time influences this?

One point I would make is that I have found that they prefer to be pricked out very early, if you do it at all. I do this before the cotyledons have even fully expanded - by which time the root can be 5 cm long already. Any later and losses seem much higher.

As Lesley suggests - it does seem very slow to mature. I have a plant on the rock garden which has flowered now for several years and is probably around 12 years old - seedlings from this have been sold by me at shows several times. Sometimes the flowers abort, probably weather related. Two other plants (in pots) are 5 years old and look like they might flower this year for the first time.

In the wild it apparently is found on acid soil but ours is planted in thin soil of pH 7.7 over limestone rubble and is happy. That said, the best plant I have ever seen was in a garden at Penrith in acid soil over sandstone - the plant was so big we thought it was a yellow peony from a distance.

[Hoy]

Here are seedlings of Pulsatilla aurea (Gabriela seed) sown this winter.
Pulsatilla does not always germinate but this winter all my species have germinated and grown well  - so far. I usually blame the slugs if they do not appear in the garden when I have planted them out.

[shelagh]

We have grown Pulsatilla albana aurea from Gothenberg seed very successfully.  Just coming in to flower, if it ever stops raining I'll take a pic.

[Gabriela]

Trond - I am so happy to see yours!
I also blame the fact I tried them under lights indoors.

[Tristan_He]

Not a yellow flowered Pulsatilla but the attached picture shows seedlings of P. alpina (subspecies unknown) sown this winter. As others observed they seemed to be 'sulking' - not dying back but not growing either, so following Darren's approach I repotted the whole lot very carefully into a larger pot with some richer compost. This seems to have done the trick and they are now growing nicely. If anyone wants to send me some seed of a yellow flowered species I will repeat the experiment 

One interesting thing about this species is that the second leaves seem to come not from the centre of the cotyledons as is usual, but from somewhere below ground.

[Hoy]

....

One interesting thing about this species is that the second leaves seem to come not from the centre of the cotyledons as is usual, but from somewhere below ground.

The true leaves come from the point between the hypocotyle and the radicle.

[greenspan]

i only just found this thread today...i want to give some infos about my experiences with Pulsatilla aurea. at first...P. aurea has nothing to do with P. albana "aurea". unfortunately some seed collectors brought P. albana under "P. aurea" into our hobby. both species are native in the caucasus region but that's all, what they have in common. P. aurea seems to be closely related to the P. alpina complex + in my opinion this alpine-species seems to need a quite special treatment to keep alive for a longer time in our lowland climate conditions

in august 2014 i got fresh aurea seed from a czech seed collector. i had a few aurea plants before (seedling quality) but they rotted within 2 years in a humus rich-sandy soil. with this experiences i mixed a sowing substrate with pure peat and a bit sharp sand. i only watered with rainwater with a ph-value about 3,5-4 adding a bit sulphuric acid (battery acid) to the rainwater. the seedbox was stored in a cold, frostfree greenhouse while the winter + i had a very good germination rate. as far as i remember, the germination started in february/march, still quite cold in the greenhouse. from then on i watered with the same acid water plus some fertilizer (liquid fertilizer for rhododendron). the growth was very good. i got seedlings like picture-perfect (see seedling example on a 7-cm pot for comparison). i potted more than 100 perfect seedlings. a few very poor + tiny seedlings remained + i didn't want to throw them away, so i planted them just for fun in a minimoor where some Sarracenia, Platanthera ciliaris, Pogonia, Calopogon and other moor-plants grow.

to cut a long story short...all potted aurea seedlings died within 2 months...always the same effect...rotting. but the poor seedlings in my moor growed on, slowly but healthy. i have to say, that i keep the moor constantly very acid with the same method (rainwater with sulphuric acid with a ph about 3,5-4 or with my groundwater with a carbonate hardness about 6 but just gave a bit more sulphuric acid to get the the same low ph-value). i didn't have done this with the potted seedlings because the normal rainfall held the substrate moist enough and this was the problem...rainwater has a ph-value about 6,5!!! the aurea in my moor had no problems with the very wet soil, not even in dormancy while the most wet winter period. i guess the moist/wet conditions are necessary for this high-alpine plant in an exposed sunny place in our lowland conditions. i was very surprised when one of the "poor" 2015-seedling first flowered in 2016 

[greenspan]

p.s. my "acid"-treatment is the same with P. alpina ssp. apiifolia, P. sugawarai, P. tatewakii, P. ajanensis, P. sherfelii (= P. alpina ssp. alba) + P. vernalis, all planted in a little mound with peat soil mixed with sand + lava grit, not so wet like in my moor, but keeping moist especially in summer. P. ajanensis made a flower bud this autumn, waiting to flower in spring 

[Gabriela]

Thank you 'Greenspan' for sharing your experience in growing the yellow-flowered Pulsatilla sp. I had no idea that P. aurea would prefer an acidic substrate since I've never seen it in its wild habitat, which usually provide some hints for cultivation. The germination was perfect but afterwards they went downhill. Next time I'll have seeds I will definitely try your method.

[ian mcdonald]

I have had several yellow flowered Pulsatilla plants and they never survive here.

[Leena]

I have sown this 2012 as Pulsatilla alpina 'Sulphurea', I hope it is correct.
I planted three seedlings, of which one disappeared and one flowered for the first time last spring. I don't have many Pulsatillas (yet) to compare this with, but this one flowered later than Pulsatilla halleri slavica. The second picture is of it a week later than the first picture.