In situ seeding of natural crevices, dry stone walls?

[JohnMcMillan]

Has anyone ever seen a discussion in a book, blog etc. about seeding natural crevices or dry stone walls? We have a garden in Cumbria on tuff, surrounded by dry stone walls. There are lots of different habitats, some sunny (today), more shaded, most mossy.  I'd like to try seeding them. I know Farrer used a shotgun, but I'm not sure I want to try that.  One of the obvious problems is that it rains here. Lots.  So fine seed just tipped into a crack is unlikely to stay there.  I found some US discussion about hydroseeding and gel/tackifier mixes.  This was mainly aimed at people who were trying to create large scale lawns in deserts.  Is there an alpine version of this? Or is it better to germinate seed in pots/trays and transplant seedlings to the rocks?  Again are there any good procedures/recipes for transplanting and stabilising seedlings.   Lastly is there a good source of plant suggestions for mossy shaded rocks?

[Maggi Young]

Hello John, I cannot  remember  if  this  was  from a  journal article,  personal communication or a talk, in the  past - but  I  recall instructions for  mixing seed  in sticky soil/clay and  splattering that  into the  crevices of  the walls  of  an old quarry  ( in which case  it  would  have been Sheila  Maule's garden) or  up steep slopes  into more  natural rocks -(in which case  it  would  have  been Hillary Hill in Argyll). It  seemed  to  work pretty  well.
 If  your  desired  seeding  position is  a wall, then it  should  be  slightly  easier  (!!) for  you  to splodge such seedy  parcels  into suitable  gaps  and  hope that the  substrate  will keep it  there long enough  for the  seeds  to establish and make  their  own way in situ.
Sounds  like  a  fun job, anyhow!  Enjoy, and we'll look forward  to seeing the  photos  in due  course  of  your  flowering  wall!

[ian mcdonald]

I think I read somewhere about encouraging moss to grow quickly on a hyper-tufa wall or troughs. The idea was to make a thick rice sludge and smear it on the surface. This would allow moss "seeds" to blow on the wind and stick to the coating. It might encourage birds etc. to eat the rice though?

[Tristan_He]

Hi John,

I have not tried seeding but have played around quite a lot with trying to establish plants in and on top of dry stone walls (I think I posted a thread about this some time ago but can't find it now). It's not as easy as you might think - the compost needs to be good and wet and you need to try to establish quite a bit of soil behind the plant, otherwise they will just shrivel in dry spells . I do like the way it can keep alpines 'in character' though, and I love coming across plants in unexpected places.

Here in North Wales we often have a dry spell about now which isn't ideal for establishing small plants. If you are planting it may be better to wait until late summer / autumn when there is a bit more rainfall or even dew.

In terms of plants to try, the successes have been fairly predictable - things that like a lot of sun and are drought tolerant: Dianthus; Campanula; Sedum; Sempervivum; Saxifraga; Edraianthus; Geranium dalmaticum. I have a birdsfoot trefoil that looks great in this sort of situation but tends to get dried out every year around about flowering time, and a primrose that rather improbably does quite well. You could also try thrift and dwarf thymes, and maybe some tough bulbs that won't mind a baking like grape hyacinths and dwarf tulips.

On a shady wall, if you have some spare plants, Ramonda should cope. They are very tolerant of periodic drying out. And ferns such as Polypodium are good. Maybe also Primula auricula? Not tried any of these though.

What I will say is though, be prepared for a high failure rate, because it's harder to water, use slug pellets etc. Don't buy something rare 'for the wall' because you are likely to lose it. It's better to plant out surplus plants from things in the garden that are getting too big, or grow lots from seed.

Hope this helps and good luck - please post pics when you have got it going!

[Maggi Young]

Tristan, I think this  may be  the  thread  you  mentioned ....
http://www.srgc.net/forum/index.php?topic=14672.0       

[Tristan_He]

Thanks Maggi, yes it was! I'll post some updates on what has grown and what hasn't.

[JohnMcMillan]

Many thanks to those of you who replied, in particular Maggi's memory of the previous thread, which I hadn't seen and which I found very useful.
Thinking about it, I'm probably less interested in seeding than "trying to establish plants in and on top of dry stone walls", by whatever
method. Certainly some of the things I'm interested in need light to germinate - so making a seed-containing gloop and squeezing it into
crevices isn't going to work there. 

If you're interested in walls, you might find John Presland's site interesting. https://sites.google.com/site/wwwdrystonewallfloracouk/

I'm intending to do some more experiments though these will have to wait until I can order materials and until this dry spell ends.  I'm currently spending about 45 minutes a day watering, a procedure normally unknown in Cumbria.  I'll write them up for the "gardened wall" thread.