On the 26th July 2020 we took a trip to Tregrehan to study Hydrangeas, however of course we were a bit side-tracked with other things, as you will see below.
A most confusing subject with much renaming and juggling of classifications. Quite how you decide what is aspera ssp. sargentiana and aspera ssp. Villosa Group remains a mystery which was not revealed during our tour.
The late flowering Hydrangea aspera ssp. robusta ‘Titania’.
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Hydrangea chinensis aff. (Wilson collection).
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Dichroa ‘Cambridge Blue’ – excellent and a plant to get.
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Bowkeria citrodora from South America (rather different to the one Burncoose stocks).
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Callicarpa formosana (FMWJ 14533) – a species new to us which looks like a viburnum. Introduced by Crûg Farm.
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Hydrangea angustipetala with gorgeous bark. Fifteen feet in height and grown as a trio.
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Rhododendron nuttallii from Vietnam – the best plants I have ever seen. Perfectly hardy.
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Hydrangea sargentiana from the original wild Borde Hill introduction plants.
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Hydrangea aspera villosa – Gongshan – the best hydrangea today bar far.
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Hydrangea anomala ssp. anomala from Sikkim growing up a tree and as groundcover. Rooted material was given to us. Huge leaves.
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The very rare Rhododendron goreri which is close to Rh. nuttallii.
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




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Following our visit to Tregrehan I received this email from Tom:
From: Tom Hudson
Sent: 12 August 2020 16:12
To: Charles Williams PA
Subject: HYdrangeas
Hello Charles,
The reply from Maurice was interesting on a couple of points.
But as he pointed out the latest taxonomic revision doesn’t really help us at all horticulturally….whats new?
H. petiolaris is elevated to full species status.
H. scandens chinensis and angustipetala have both been lumped into chinensis.
H. davidii in his opinion warrants specific status although it is lumped into chinensis by McClintock.
We forgot to look at H. longifolia which I really rate as a plant, lovely foliage although flowers a bit on the small side.
I will propagate the white Dichroa as I need to trial it outside properly.
The later flowering villosa collections looking really good now.
No new update on the Callicarpa info from KR on his Vietnam one but he is due a visit soon.
All the best,
Tom