Primula 2010

[Gerdk]

Despite cold and snow and a shortage of light Primula 'Blue Wave' is flowering - a gift from a nice Forum member!

Gerd

[Ragged Robin]

Wow,Gerd, that is absolutely gorgeous - what a colour - a really cool photo

[David Nicholson]

Nice to see it Gerd and it's a long way in front of my own plants

[sippa]

Hi -- Blooming in my greenhouse right now.  As we are in full winter it brings a breath of spring


Marianne
Vermont, USA

[Carlo]

Well done, Marianne. Very nice. What else have you got tucked away in there?

[Lesley Cox]

Very lovely Marianne. Is it a cultivar of P. allionii?

edit:
 ...answered in this post on page three: http://www.srgc.org.uk/smf/index.php?topic=4976.msg142008#msg142008

 it's P. allionii 'Anna Griffith'

[David Sellars]

Here's a species Primula allionii flowering in a vertical piece of tufa last weekend. I inserted a small rooted cutting in the tufa almost a year ago and the plant is still very small.

[Ragged Robin]

Blooming in my greenhouse right now.  As we are in full winter it brings a breath of spring

A really lovely Primula, Marianne, such a delicate pink to start your 'Spring in the greenhouse', congratualtions 

[Ragged Robin]

Here's a species Primula allionii flowering in a vertical piece of tufa last weekend. I inserted a small rooted cutting in the tufa almost a year ago and the plant is still very small.

David, that's a great success story - your Primula allionii cutting obviously loves tufa!  I have never grown plants in tufa and wonder how different the conditions are to growing amongst rocks?

[David Sellars]

Robin:

You are right.  Plants in tufa grow differently compared with plants amongst rocks.  The main difference is that they grow much more slowly so they retain a compact habit if you like that kind of thing.  I certainly do.  So you need lots of patience both watching them grow and also planting in tufa as the technique is quite exacting and takes time. The good news is that you can fit lots of plants into one tufa block so it is a great space saver.

One observation that I have not seen in the literature, is that plants in tufa flower more readily than in regular rock garden soil.  My theory is that they are a little more stressed which brings on flowering.  I have very small Kabschia Saxes that I planted last year that have already flowered this year.

Of course you can really only grow lime-loving or lime tolerant plants in tufa. I like to choose plants that have a natural habitat on vertical limestone rock such as Primula allionii and Saxifraga longifolia. I have found it best to have tufa beds mostly north facing as they could have a tendency to dry out in the summer. Plants that grow on vertical rock also tend to like north facing slopes so that works out well.

If you have the patience (and the tufa), try it.  If you love alpine plants you will love tufa!

[Ragged Robin]

If you have the patience (and the tufa), try it.  If you love alpine plants you will love tufa!

Now there's a challenge.....but no idea if tufa is available here....there are limestone outcrops in the region and locally we're on granite but i would love to grow lime-loving alpines if I can.  Thanks for your detailed information David 

[sippa]

David, lovely little plant.  I wish I could grow allionii outside, but I am afraid the climate is too harsh.  When I have a larger supply I will try your method in tufa.


Marianne

[David Sellars]

Marianne:

I could not keep the species Primula allionii alive in our climate until I tried tufa.  Allionii hybrids have been OK though in regular rock garden soil. 

I think if you can replicate the natural habitat (to the extent possible) you have a better chance.  They do seem to prefer growing in a vertical limestone face.  I have a winter rain shelter over that part of the tufa garden which may also help.

[Lori S.]

I wish I could grow allionii outside, but I am afraid the climate is too harsh.  

I wonder if it is not cold-hardiness that is the limiting factor there, but conditions (e.g. winter wet, as may have been alluded to in David's comments), since P. allionii cultivars (I don't have the "straight species") grow outdoors here in regular soil in this cold but dry climate?  (On the other hand, perhaps mine are P. allionii hybrids and thus I am seeing some hybrid vigour?)

[Maggi Young]

I believe that it is winter wet which is a problem ....and here, in Aberdeen, the next problem is summer wet!  These plants just don't enjoy sitting about in the rain.... who could blame them/