Are you willing to start from seed?

https://www.jelitto.com/Seed/Perennials/HEUCHERA+sanguinea+White+Cloud+Portion+s.html

I'd rather not. But if that is my only choice, then I would give it a try. Thank you.

What is it about these cultivars that makes you want have these specifically? Asking because there are seemingly endless varieties of heuchera, something with green leaves and white flowers shouldn't be difficult to find if you can't find those specific cultivars.

" endless varieties of heuchera, something with green leaves and white flowers shouldn't be difficult to find "

Actually, green leaved heucheras with white flowers are not all that common. Pink to red flowers tend to rule the day :-) You might want to see if you can find June Bride or Autumn Bride if growing from seed is not your thing.

And while it is not a solid green leaf, it is more green than not until winter coloration but Green Spice produces white flowers. I also consider it to be one of the best performing heuchs of all time!!

There seem to be very few green leaved white flowered cultivars on the market these days, as Gardengal mentioned. I suppose I mentioned 'White Clouds' because I grew it once upon a time and liked it. The fact that it is a Heuchera sanguinea cultivar rather than a cross is an added plus for me. I am not growing a strictly native garden - far from it - but I enjoy using as many natives as possible.

'June Bride' seems to be almost as difficult to find. It could be a substitute though. I have seen 'Autumn Bride' listed, but the pictures I've seen show a heavy, clumsy looking flower cluster, not the graceful wand of 'White Clouds'.

Also, I just hate seeing excellent cultivars disappear due to changes in fashion. I get it that heucheras make wonderful and useful colored foliage plants, but it seems to me that their role as actual flowers that happen to have nice foliage as a bonus is being lost.

I am not familiar with 'Green Spice'. I will take a look at it, thanks!