Astragalus whitneyi

[ronm]

Seed of this ( I believe ) very special Astragalus sp. is with me now. I am determined that it will grow well and be passed around as I really think it deserves to be, and has ( as far as I'm aware ) not yet been done so.

http://www.wnps.org/plants/astragalus_whitneyi.htm

It has been indicated to me on the NARGS Forum that the seed is easy to germinate. Can anyone add any cultural advice based on experience in UK conditions please? I'm pretty confident that I should be able to grow it well, but any advice is most appreciated,

[Lesley Cox]

No help at all Ron but what super pods. Something really to look forward to. Best wishes with it.

[Maggi Young]

I'm no help either- just saying well done on getting the seed - it's from an area of serpentine rock, isn't it? 
Beautiful thing.

[ronm]

Thanks Lesley and Maggi for your best wishes with this  sp. and subsp. 

I am finding that there are some superb plants growing on these Serpentine soils and that they appear to be rarely cultivated. I'm not quite sure why this is as they appear to respond well to a 'normal' alpine cultural regime given a knowledge of rainfall and snowfall in the regions where they grow. Given success with a number of these plants I feel confident trying these Astragalus and the previous posted Viola beckwithii, and others of similar requirements. My concern is that I may be missing a trick in the long term and will be taking on a series of plants that appear to flourish in the short term, but will perish in the long term due to my inadequate knowledge. This I don't want to do as I know these are not common plants in nature, as their Serpentine ecosystems are specialised and restricted.

[Tim Ingram]

Ron - so far I've only had really good success with Astragalus utahensis. I've always thought these would be ideal subjects for a deep sand bed, but the rainfall where many grow is so low that protection is likely to be necessary unless in pots in an alpine house. The best advice probably comes from people like Graham Nicholls (in his book 'Alpine Plants of North America') and from Anne Speigel. I think a lot of playing with small seedlings and experimenting is likely to be the only way of finding what suits your climate and conditions. Sowing seed in situ in a sand or crevice bed could be good way to go because pricking out seedlings is a delicate business and those roots want to go straight down! Like you I would be fascinated to hear from anyone who is growing these well.

[Mark Griffiths]

Re the serpentine thing I read somewhere that serpentine is rich in base metals and so is toxic to many organisms including alot of fungi - that was then connected to poor natural resistance to fungal attack by plants that are restricted to serpentine rocks. I think Cyclamen alpinum is an example. I may have misremembered or even made it up myself.

Only advice I can give is to pot up seedlings quickly otherwise the tap root goes down and they don't like being moved. 

[Susan Band]

I have in the past grown some of these type of astragalus. The seed needs to be scratched (rubbed on sandpaper) before you sow it then it germinates within a couple of days. I would advise making sure you leave the sowing until you are nearly ready to plant it as they will grow on quickly. Try starting the seed off in perlite then either planting them in situ or into long root trainer plugs.
I had it growing, flowering and setting seed in a trough many moons ago.
By coincidence it was for plants like this I was looking for perlite plugs as I fancy starting to grow them again.

Susan

[ronm]

Thank you Tim, Mark and Susan for all the information and advice. 

Mark, you certainly didn't make up the information regarding serpentine soil conditions. They are particularly harsh and indeed toxic to many organisms, although it is well known that the vast majority of plants tolerant of serpentine soils are involved in mycorrhizal associations.

I'll sow in March, in situ, in deep beds in a large polytunnel. I have two subsp. ( ssp. whitneyi and ssp. siskiyouensis ), which will grow in separate beds.

I think your idea re Perlite plugs is very good. Did you manage to find a source?

[Susan Band]

Ron,
No I didn't find a source of the plugs. I got an answer from the Dutch company but I could only order them by the pallet which I thought was a bit extravagant for trail purposes. Will still try and work something out.
You prompted me to add a few  Astragulus to my Alpains order 
Susan

[astragalus]

Astragalus whitneyi is certainly a great one to have.  All astragali supposedly have an alelopathic (sp?) reaction which basically means they can kill each other off if sown in the same pot.  I really have not had this problem.  All my fabaceae seeds are scarified and planted in 3" pots no more than two or three to a pot for ease of separating them.  After the true leaves appear I start separating them and pot them up in a very gravelly, sandy, loose mix.  They are put into the garden the first year, sometimes in early fall if the growth has been slow.  I water the pot two days before removing the seedling and then tip everything out on damp paper and some turface.  The garden mix is also gravelly, sandy, and very fast draining.  Some subsoil (mostly clay) is used in the mix, no peat at all.  This has worked well for the american astragali, some of which grow in areas where 6" of rain is a good year.  All of mine are planted in very sunny, windy conditions.  I've had wonderful germination with Alplains Seed.  You should try more of them, Alan Bradshaw has a wonderful selection with rarities like Astragalus lutosus.  Apparently, collecting the seed in habitat is a death defying experience!  Astragalus spatulatus is an excellent one to grow and A. crassicarpus has wonderful large, cherry-colored pods. 

[astragalus]

And here's a photo of Astragalus lutosus, my favorite, grown from Alplains Seed, and collected in a very steep sliding scree above huge sheer cliffs.  And Alan Bradshaw survived the collecting experience although I think his backpack took a 700' freefall over a cliff.

[ronm]

Firstly, WOW what a beautiful classy plant, A. lutosus. I can see how that can become a favourite in a genus that contains some very interesting and stylish plants.

I didn't know that all Astragalus contain the chemicals for negative allelopathy. Should have done my homework   Bad news for me as my intention was to grow these in beds specifically constructed for growing the Fritillaria of the serpentine soils and talus / screes. I was hoping some 'companion plantings' ( Astragalus, Viola, Silene etc.) would produce a more aesthetic group of beds, hence my taking on these seeds. Now it seems there is a chance of them being bad 'bedfellows', I cannot take the risk. It'll have to be a small bed of their own,  Thank you so much for sharing this information. [ You may not have noticed any effects of this as it is usually designed to prevent other species of plants from germinating/ growing close to the plant in question, and not its kith and kin ]

Alplains certainly do have a wonderful range of sp. of this genus. Did you manage to resist many of them Susan?