Description horticole :

Plantsman Preference 2016 (UK)

New in 2014. (G. platypetalum x G. gymnocaulon)

Excellent clumps of felted grey-green foliage are covered by masses of large, deep, indigo blue flowers tinted purple in the veins. Average soil in sun. 40cm.

We have had this variety without a name for many years but it is only recently that we talked to some other growers about it.  The exact origin is a little vague but when we obtained it we were told that it had come from Bill Baker, unfortunately it is, of course, too late to ask him about it.  Alan Bremner did make this cross but he tells us that his plants weren't distributed so we assume that this cultivar did not originate with him.

One of the most striking things about Geranium 'Blue Thunder' is the depth of colour in the flowers, it is a real indigo base which can only have come from Geranium gymnocaulon (if you don't know Geranium gymnocaulon, it has deep indigo blue flowers but they are a poor shape and the plant a little difficult to grow).  Geranium platypetalum brings a much better habit, flower shape and floriferousness to this hybrid.

Geranium 'Blue Thunder' has proved to be easy to grow in drained soil in full sun and long lived.

Named by The Plantsman's Preference, in conjunction with Robin Moss in the Hardy Plant Society Geranium Group newsletter in 2014.

Notes :

Notes de Robin Moss (UK) in Newslettre, spring 2014, geranium group of HPS.

Amongst the most beautiful plants I have had in the garden for some years, is a clump of a hybrid gymnocaulon x platypetalum. I am certain that this originated from material I had from Alan Bremner, who certainly made this cross. Several nurseries sold this plant under this hybrid description (without a cultivar name) and I always assumed it was from the same source - Bremner material that found its way into nurseries, something that happened with several of his plants. For example, ‘Solitaire', before it was named, was sold with the parental hybrid name. However, chatting to Tim Fuller of Plantsman's Preference, he showed me the same plant and said how much he liked it. It has the most intense dark blackish blue colour with really heavy black veining. He had always assumed it came from Bill Baker but David Victor would neither confirm nor deny this. Bill Baker's material had allegedly not come from Alan Bremner. Tim and I both think the plant should be named. I can now report that, having debated the issue, we have named the plant ‘Blue Thunder'. Anyone with further information should contact either Tim or myself.