Androsace yargongensis – an update
Don Peace
The ACE expedition of 1994 provided a very significant quantity of seed from this species, giving many growers their first opportunity to grow plants from different collection sites in Yunnan. The KGB expedition, only a few months earlier, also brought back seed of A. yargongensis (in the guise of A. aff. delavayi), and various much smaller scale collections in more recent years have provided further material for us to experiment with. So how well established is this desirable species and what have we learned about its requirements in cultivation?
The ACE seed germinated readily and many plants were seen and reported. The species became available in the specialist UK nursery trade particularly during 1998 & 1999 (interestingly all of those I could trace were ACE1722 and often the same clone that was ‘passed around’ and bulked up from cuttings). Plants have also been available in North America and in mainland Europe (particularly in Holland). However, in the current year I saw very little A. yargongensis on nurserymen’s stalls – several having reported difficulty in maintaining good stock levels.
The KGB expedition made five collections of A. aff. delavayi (numbers 223, 328, 350, 450 & 523). I am not aware of many plants arising from the various collections of A. aff. delavayi but some plants do exist and what evidence I have suggests these may all be A. yargongensis. Goteborg Botanic Gardens have been unable to confirm identity as they had very little success with these plants and currently have no live material. Does anybody have plants of the KGB aff. delavayi or information about their true identity?
Mike Bramley donated seed to the Group’s exchange in 1997 following his trip to China and I know of plants that originate from this source. In the same year the Group’s exchange contained seed donated by George Young and recorded as wild collected from the same location – George however tells me that he was not on the same trip and that his seed was ‘garden collected’ from 1st generation ACE plants (sorry George – the error was ours). I’m not aware of any plants from this source, but please amend your records if you are lucky enough to have any. Pete Boardman and Dieter Zschummel have also provided us with new seed in recent years.
Whilst almost all the collections that I’m aware of have been made in Yunnan, and more particularly on the Biema Shan or Big Snow Mountain, Pete Boardman donated seed to the 1998 exchange from the hills south and west of Litang in West Sichuan. I’m not aware of anyone successfully germinating seed from this source. Pete tells me that identification was not 100% certain and in view of the different location it would be very interesting to compare plants if any are available. [Does anyone have plants from this source?]
In common with most of section Chamaejasme, A. yargongensis is essentially self-sterile but seed is forthcoming if different plants are placed close to each other at flowering time (allowing flies to do the pollinating). I’m sure that more seed is produced if less related plants are used (e.g. a plant from the ACE 1722 collection next to one from ACE 1465) - but perhaps this is illusory. I now have a good number of 2nd generation seedlings from ACE material and this year obtained sufficient seed from ACE1722 plants to put some into the Group’s seed exchange.
An interesting point mentioned to me by Dieter Zschummel is that fresh seed tends not to germinate until the following spring whilst ‘old’ seed sown at the same time (mid to late summer) will literally germinate within a few days. Records of my own sowings have revealed the same propensity.
Having canvassed our entire membership (both via the Newsletter and by email) and spoken to several nurseryman and growers both in the UK and overseas there seems to be relatively little material resulting from this very significant influx of seed. Why should this be? I think that the plant is very difficult to please. In one sense it is easy to grow, and also easy to propagate (from cuttings and from seed) but it is far from easy to produce a ‘nice’ plant. It becomes ‘untidy’, the lower stems become brittle and the plant DIES.
After receiving a Preliminary Commendation in 1998 with a plant from original ACE1465 seed, and a Certificate of Merit for a plant of ACE1722 during the current show season, I have a very soft spot for A. yargongensis. However I have to grow many plants and provide a disproportionate amount of attention to please this splendid but recalcitrant species.
Ray Fairbairn (our seed exchange manager), whose plant was the first that I saw reach the show bench, tells me that initially it was an easy and super plant, but he has since had great difficulty in reproducing this early success in spite of ample material and opportunity. How many times have we known this phenomenon in relation to new introductions?
Several growers have mentioned that plants can appear most unhappy in mid-winter, becoming brown and seemingly lifeless, and then miraculously revive in early spring (if you’re lucky!). More unusually, plants often degenerate quickly as they mature, even during the summer. Not only do they go brown in the centre but also the mature stems become very fragile so that the plant becomes almost impossible to handle. I have had some success by repotting at depth so that the entire lower stem is covered with compost and only the current growth at the tips remains exposed. This mimics the conditions experienced by plants that naturally grow in unstable screes (situations where they receive frequent 'top dressing'). However the field notes from both ACE and KGB collections refer to stable scree and Dieter Zschummel confirms this from his own observations.
The difference between plants grown under glass and those outside is very marked – during the growing season, indoor plants rapidly become extremely etiolated. This is very similar to the behaviour of other Himalayans e.g. A. mucronifolia, but does provide much better (or at least much easier) cuttings. This species also seems particularly susceptible to aphid and to red spider mite (even outside!). One grower has mentioned that “whitefly love A. yargongensis”.
Several growers have reported significant variability in both habit and form – some clones being much more compact than others. Hopefully after a few generations we will achieve a few good clones that are well behaved, relatively easy to grow and compact in habit. As mentioned earlier, individual plants are affected greatly by whether they are in the open or under glass during the growing season. In my own experience, (North East of England), the plants that are completely exposed to every bit of summer sunshine (but with lots of water) are the best plants. Growers further south prefer to provide some shade against the midday sun.
A number of members have reported attempts to grow A. yargongensis outdoors throughout the year. The success rate has so far been very discouraging. Experiments continue, particular with the use of tufa, and hopefully the secret will eventually be found. In the meanwhile, I would not advise planting out your only specimen!
If you already have this species then please keep propagating and growing it. If you don’t yet have a plant then try to obtain one. In spite of all the difficulties, it can make a super plant and when in full flower is an absolute delight.
For reference here are the notes and collection numbers from the ACE and KGB expeditions.
[ A. axillaris ] [A. baltistanica ] [A. hausmannii] [A. hirtella] [A. x marpensis] [A. minor] [A. sarmentosa] [A. SQAE265] [A. yargongensis]
