White Summer-flowering Geranium for Sunny Rose Border?

Nollie

I am a bit bamboozled by the huge range of hardy geranium species. Although I have avoided the ones solely for shade/part shade, most others still say for full sun/part shade, which makes me wonder how heat-tolerant they really would be in my location.

These are the white(ish) full sun/part shade ones I can get, are any a safer bet than the others or are they all roughly the same?

G. Cantabrigiense ‘Biokovo’ (blush, May-July) G. Clerkii ‘Kashmir White’ (purple veining, Jun-Sept) G. LambertiixTraversii ‘Coombland White’ (similar to above, leaves look stouter, June-Sept) G. Pratense ‘Laura’ (the only pure white, pretty semi-double, June-Sept)

Any thoughts, kind people?

Obelixx

Renardii?  Good in full sun in poor soils and has good foliage too.  White flowers with purple veins - https://www.rhs.org.uk/Plants/7924/i-Geranium-renardii-i/Details 

floralies

I have tried hardy geraniums here @Nollie, without much success. I planted a few in full sun of which only one white one survived but I'm afraid I don't know the name of it. all the others just frazzled in the heat. The only geranium that grows well in my garden is Psilostemon, but that's the wrong colour for you!

Borderline

Not familiar with the ones you have listed but from my experience, Geranium Sanguineum ‘Album’ can do well in dry conditions. Geranium Pyrenaicum ‘Summer Snow’ normally available in seeds are tough plants, they prefer hot and dry conditions. 

Singing Gardener

I have Geranium Sanguineum 'Album' in my sun-baked border and it does very well. The flowers are quite small though compared to some other varieties.

Topbird

Cantabrigiense Biokovo does ok in a very dry border here. It forms a mat which is nearly evergreen and takes easily from bits pulled off with a scrap of root. The only downside is that the flowers only last a few weeks.

An alternative to consider might be a white heliantheum. Similar form to a geranium and seems to do well in my south facing very dry gravel garden.

Nollie

@Obelixx , @Borderline and @Singing Gardener thanks very much for your suggestions, what would I do without you guys! I have added Renardi and Sanguineum Album to my list. Actually both are available, but weirdly did not come up when I searched the nursery site for white geranium in full sun, although are exactly that...

Doing some more research, Kashmir White is off (hates it hot and humid) and Laura, said to flower for ‘several weeks’ on some sites, which sounds short compared to others plus I have a feeling she might be a bit fussy... So revised list:

Coombland White
Biokovo
Renardi
Sanguineum Album

@floralies, yes it’s the frazzling I am concerned about most, as I can give them good soil and plenty of water. Rozanne does fine here if watered well, apart from this year when she frazzled too. Shame you can’t remember the name of your white one, do you have any photos of it by any chance?!

floralies

@Nollie, I'm afraid I don't have a photo of it, but I imagine it may be Sanguinium Album. They don't sell many geraniums in these parts probably because they don't do well. I will have a look in the GC and see if I can see one. I bought three about four years ago and only one survived.

Nollie

Not to worry, thanks @floralies. They don’t sell many geraniums here either, but that’s because they don’t sell many perennials period. I have to get mine mailorder from your side of the Pyrenees!