Ostrowskia magnifica

[Gene Mirro]

I have a few seeds of Ostrowskia (after a lifetime of seeking it).  Does anyone have experience growing it from seed?  All I can find is a note in Deno's book that says it will germinate at 40F, but that it goes dormant shortly thereafter, and is very difficult to keep.  Also, the Archibalds say that its growth pattern is similar to Eremurus.  Any suggestions?

[Lesley Cox]

I germinated some from Pilous seed a couple of years ago (he lists it again this year) and they stayed as cotyledon leaves for about 4 months then died down. In the pots when emptied, were a dozen or so little white tubers. I repotted them and lost them during the coming winter, not to frost but I suspect to their being too damp in my shady tunnel house. I also wish I'd not tipped them out after just the one season. I'm trying more this year and will leave any that germinate in the seed pot for at least another year, well drained at all times.

[Gene Mirro]

If they are like Eremurus, they germinate and grow in spring, then go dormant in summer, to survive the dry, hot conditions.  So maybe the dry warm dormancy has become a requirement.  When a gardener sees the plant wilting away in early summer, what is the first thing we do?  Water it.  Maybe we're killing it with kindness.  

This is all hypothetical, of course.  Does anyone know for sure?

[Gene Mirro]

I've been learning.  After sowing, keep them warm for two weeks or so, then cold for a month or two, and they will germinate while it is still cold.  Give them lots of light as soon as they germinate.  I put them under fluorescents at about 60F (15C).  Feed with soluble fertilizer.  They need a deep pot and porous soil.  They will not bloom until the roots are very large, so if you grow them in a one-gallon pot, they may never bloom.  I am growing them in 12 inch deep bands from Anderson Die in Portland, Oregon.   http://www.andersonpots.com/products.html



In the foreground are some young plants growing in a 2.6 liter square pot.    Behind the big Ostrowskias are Tropaeolum polyphyllum and Echium wildpreti, both of which need deep containers.

They go dormant in midsummer.  They need several months of warm dry dormancy, followed by several months of cold dormancy.  If they don't get the warm dormancy, you will probably lose them.  I lost my first ones that way. I let the mix get somewhat, but not completely, dry during the dormant period.  I keep them in my nursery fridge during Winter, so they don't freeze.

Some people say to grow them outdoors, but this plant is too rare for that, IMO.  The birds and slugs will get the emerging shoots.  I tried it one year.  One plant made a big bud, but it never opened, probably because of our wet, dark springs in the Pacific Northwest.  The potted plants still haven't bloomed for me, but I am optimistic about the ones in the deep bands.

The only good seed I ever got was from Jim Archibald, who said he was growing them outside against a south-facing wall.  Exchange seed has never germinated for me.  Maybe some forum members could exchange seed among themselves of short-lived seed like this.  If you mail these seeds, it is essential to pad the envelope, since the seeds are soft and oily, and will be crushed by the post office sorting machine.  I see that Rareplants is selling the plants for 22 pounds each.

This plant has to be the granddaddy of Platycodon, which is super-easy to grow.  

[Lesley Cox]

They look good Gene. Keep it up! I had seed from Jan Jilek a few years ago and that germinated but they didn't grow on as far as yours have before dying off.

[JustG]

Greetings

Would someone be so kind as to give me a contact for Mr V Pilous or anyone else who can supply seed.

I recieved some good quality seed of Ostrowskia magnifica a few years ago from this gentleman but i have lost his email address.

Many thanks

[David Nicholson]

vlpilousATseznam.cz

replace AT with @ as usual

[JustG]

Many thanks David.

[Gene Mirro]

I can keep my plants alive, but they will not bloom.  I've given them a very deep root run, but I'm afraid that they emerge too early in Spring, when there isn't much sunlight in this climate.  I've tried supplemental light, but it doesn't seem to help.  I have tried them outdoors, but they do not do well.  I am running out of ideas. 

Jim Archibald said they come from the same region as Eremurus, which grows very well for me here.  But the Ostrowskias come up and make leaves, and in a few weeks they go dormant again.

Can anyone offer advice?

[pontus]

Hello Gene,

they may be going dormant early because the black pots, which attract sunlight, may get too warm? and therefore the soil and root gets too warm and decides to go dormant?  have you tried then in half shade? or like lilies, plunging the pot in the ground, with groundcover, and then having the plants head in the sun?

I have been tempted many times by this plant, but have always halted and not bought one because of my fear that it will start growth too early in my poorly lit garden shed in a pot.....just like i have always wanted to try canariana canariensis...but that would be the same problem..it will start growth too early i think....

have you tried cold stooring the ostrowskia roots in a nursery fridge untill perhaps march/april, and planting them when there is sufficient light and warmth outdoors, and then, if buds form and it gets too cold, bring the pot inside in a veranda or a windowsill?

Pontus

[Gene Mirro]

I have tried storing the potted plants in the fridge until mid-April.  Then I place them in the cold greenhouse.  But they do the same thing:  grow for a few weeks, then go dormant. 

I also tried them in the open ground.  They came up in April, when it was dark and rainy for weeks.  One plant tried to bloom, but there wasn't enough heat to open the bud.  After a few weeks, they went dormant.

I like your theory about keeping the soil cool.  I will work on that this Spring. 

It is easy to understand why this plant is almost never available.

[Gene Mirro]

Blooms at last:



Four tall stems with one bud per stem.  The leaves have wilted, but the buds are opening.  I don't know if I will be able to collect seed.  I didn't chill the roots or do anything special.  They are in the cool greenhouse.  I'm beginning to think that it is just a function of root size.  They are in a huge deep pot, so the roots are probably quite large now after 5 years.  This fall I will plant some of the roots in the open ground.  This is a very difficult plant.

The flower looks just like a giant pink Platycodon, but the bullet-shaped bud is quite different, and the plant does not behave anything like the very easy Platycodon.

[Maggi Young]

 Tim Ingram has made a midsummer diary about this plant  - you can read it here

A reader has replied to Tim that she is having some difficulties with the plant as well - there seems to be a lot of that about. 

Paige Woodward in Canada has written on the Hillkeep site that  :
"Our plants descend from material collected by Arnis Seisums in the Hissar Range of Tajikistan. This plant needs dry Central Asian conditions to thrive, but on account of its size it is unlikely to survive in a pot smaller than 15 liters (4 gal.). Seisums grows it in an open bed, lifting it after it flowers and keeping it dry till the end of September. We grow ours in pots in a cool glasshouse. We don't lift after blooming, but we water frugally and when the leaves die down we stop watering completely till the first green tip emerges."

I reckon since he's actually begun to get blooms that it won't be too long before Gene is showing us a plant with many flowers.....

[Tim Ingram]

Thanks Maggi for correcting my reference to the Hillkeep site (why did I think ca meant California?; lazy of me). Very interesting to read more about this plant and Gene's experiences. Adrian Cooper grows many of the dry-land irises extremely well and so gives this plant a similar situation, though it flowers a good bit later. His plant though is under cover in an alpine house, but he grows many irises outside in a narrow bed next to the greenhouse (hot and dry) and there must be a good chance that Ostrowskia would grow here too. This would be an amazing plant to get established in the garden if Farrer's words can really ring true.

[Maggi Young]

Thanks Maggi for correcting my reference to the Hillkeep site (why did I think ca meant California?; lazy of me).

I had not spotted that, Tim    I make the same mistake so often myself, but I do know Paige.