The Hard And Soft Wheats CAN be either Winter or Spring. There is both Hard Red Winter and Hard Red Spring Wheat.

The flour used for Cakes and Quick Breads are higher in starch, lower in Gluten. This is the Soft Wheat.Since enzymatic conversion turns the starch into Sugar - this kind of wheat makes better sprouts for juicing. Also used for the Rejuvelac.
The 'Stephens' variety is a Soft Winter Variety.

Whereas, Bread Flour {Strong Flour in UK} is higher in the Gluten thus protein. Its this that gums up with yeast to make the sponge, or better yield of Seitan. This the Hard Wheat. Durum Wheat is a Hard Wheat.

In modern parlance 'Red Wheats' require the bleaching to get maximum sales - because processed white wheat is the demand.

Baker Suppliers Wholesale are the best help for grains/flour prices - as for Organic the footwork will be up to you.

I, too, am interested in Rejuvelac. I'm in the Denver vicinity and am wondering if you've found soft spring wheat berries sold anywhere in this area.