pH requirements for some alpines

[JPB]

I'm about to repot my alpines. Does anyone know the preferred pH (Ranges) of the following species?:

Gentiana verna
Siderites hyssopifolius
Dianthus plumarius
Viola biflora
Phyteuma hemisphaericum
Soldanella alpina

Thanks!
Hans

[Lesley Cox]

I really can't help with anything specific except that in general, Dianthus like lime. However, I have read and I firmly believe, that lime lovers can live without it while lime haters can't live with it, so err on the neutral to acid side unless you know the plant is a lime lover, like silver saxifrages for instance.

[iann]

Gentians all need acid soil, right?  Well not this one, and not quite a few others similar to it.

[David Nicholson]

I though only the autumn flowering species needed acid soil?

[Diane Clement]

Gentians all need acid soil, right?  Well not this one, and not quite a few others similar to it. 

Gentiana clusii prefers limestone, which is one way to differentiate it from G acaulis.
G verna grows on the Burren which is limestone

[iann]

I though only the autumn flowering species needed acid soil?

That's the rule of thumb I learnt when I got past the initial myth that they all need acid soil.  I don't think it's a 100% reliable rule of thumb though.

[Lesley Cox]

I've always worked on the principle that Asian gentians need acid soil while European need (or prefer) lime. Are you saying Diane, that G. acaulis prefers an acid soil?

[Diane Clement]

Are you saying Diane, that G. acaulis prefers an acid soil? 

It's the accepted wisdom as the factor that differentiates it from G clusii.

Quote (AGS encyclopaedia): G acaulis: ... in acid grassland, stony areas and bogs 
Quote (Flora Europaea): G acaulis: Calcifuge

In that group G acaulis et al, Flora Europaea also lists as Calcifuge: G alpina, whereas the others in that group (Gg clusii, occidentalis, ligustica, dinarica and angustifolia) are listed as calcicole 

[Lesley Cox]

Well in that case my G. acaulis, isn't. It's in a rather limy raised bed. And I've been sending it as G. acaulis to the seed lists for years. I don't have either of those books/vols - or access to them - as the AGS thing was way too expensive for me at a time when I was just about without any income at all.

As it happens, and based ONLY on recent pictures on the Forum I'd been wondering if mine was G. angustifolia rather than acaulis. It is far from stemless and the leaves are perhaps more narrow than they should be for acaulis. Opinions please.

Sorry about the weeds there. They obscure the issue. I'll try another pic.

[Diane Clement]

Well in that case my G. acaulis, isn't. It's in a rather limy raised bed. And I've been sending it as G. acaulis to the seed lists for years. I don't have either of those books/vols - or access to them - as the AGS thing was way too expensive for me at a time when I was just about without any income at all.

My AGS vols I got a bargain second hand years ago for £25, although I paid extra to have it rebound.  Flora Europaea isn't mine, I can't afford it, it belongs to the AGS seed exchange, luckily I have charge of it for name checking duties.    

As it happens, and based ONLY on recent pictures on the Forum I'd been wondering if mine was G. angustifolia rather than acaulis. It is far from stemless and the leaves are perhaps more narrow than they should be for acaulis. Opinions please.  

I bow to the great knowledge of Franz H and hope he will oblige here.