I have a seed grown Flowering Currant (Ribes sanguineum) that has breezed through four winters in Kingston, Ontario and is now six feet tall. While the leaf buds appear to be very hardy and the plant has never died back, flower bud hardiness is not quite as good. This appears to be the first spring that it was prepared to flower but I have been left with 3 flowering buds (below snow level) and a whole lot of dead (brown/blk) flower 'embryos' being pushed out as the leaves unfurl. My question to the folks familiar with growing this species....At what temperature would you expect flower bud kill to commence? In my experience, while the plant itself will sail through -29Â°C (an exceptionally cold night this past winter), can I ever expect to see flowers after a more average Kingston winter (-24Â°C)?