On the road this week

Beautifully groomed: the canal at Wisley.

 Back-to back meetings of the RHS Woody Plant Committee took me south this week. On Tuesday we met at Wisley to discuss recommendations for the Award of Garden Merit, spending a long time debating the qualities of plants proposed by working groups as part of the current AGM Review process. The committee as a whole has to ratify awards, and this meeting gave the opportunity for those who wished to raise objections or make proposals. It was a good-natured and productive session.

A section of the great double borders at Wisley.

Hydrangea paniculata Vanille Fraise was proposed and recommended for the AGM: here growing on Battleston Hill.

Inside the canopy of the huge Catalpa bignonioides by the rose garden at Wisley.

To mark the WPC's visit to Kew a young Carya cathayensis was planted, all members of the committee contributing a spadeful of soil. Tony Kirkham adjusting the plant; Raymond Evison (our Chairman) with spade. This is now the only example of the species growing outside in the UK.

On Wednesday we reconvened at Kew for a formal committee meeting and study day on Juglandaceae led by Tony Kirkham and myself. We discussed the identification and diversity of the walnut family, of which Juglans, Carya, Pterocarya and Platycarya are the four genera of interest to temperate gardeners. All have potential to make beautiful trees, but many species are seldom seen outside specialist collections, possibly because they don't like transplantation or pot cultivation much. Most of us got our first sight of a specimen of the Chinese hickory Carya cathayensis in the shape of two year old plants grown from nuts sent to Kew from the Shanghai Botanical Garden. One was planted at Kew in the 1980s but soon died: hopefully these plants will be more successful.

Juglans sigillata is the most recently introduced walnut: this specimen was grown from a bag of nuts sent to me in 2005, and is now over 3 m in height.

Bedgebury National Pinetum seen from the visitor centre.

 Thursday morning found me at Bedgebury National Pinetum, Kent, to see the new propagation facility there - we are planning a modest version at the Castle Howard Arboretum. Dan Luscombe, who planned, built and runs the nursery showed me around the extremely impressive set of growing areas, where he produces large numbers of beautifully grown conifers and other woody plants each year. The majority are for use at Bedgebury, but the surplus are distributed to other collections. In recent years Dan and the Curator, Chris Johnson, have built the collection at Bedgebury to undoubted primacy in the world, with an unrivalled collection of both species and cultivars, though the Pinetum is always strapped for cash - it is sadly under-valued by the Forestry Commission which owns it.

Part of the nursery at Bedgebury National Pinetum - a huge diversity of conifers.

A superb group of my favourite conifer, Taiwania cryptomerioides, in a beautifully glaucous form.

The first known cones in Britain on Cathaya argyrophylla, a very rare Chinese larch-relative.

Cones on Picea farreri: collected in 1919 on Reginald Farrer's last expedition to Burma it was not named until 1980, and all specimens in cultivation are propagated from the single tree that survived from Farrer's seed.

Succulents on the pond terrace at Myddelton House.

Coming round the M25 on Thursday afternoon I bethought myself to visit Myddelton House, which lies barely a mile from Junction 25. I am a member of the Garden Advisory Group there, but as I can't make it to next week's meeting it seemed like an opportunity to catch up. E.A. Bowles said it was the driest garden in England and even after this year's rainfall it was looking rather dusty in parts. Andrew Turvey and his team are getting to grips with it and bringing it back into shape, with newly tackled areas to see every time one visits.

A variegated Piper capense that I found on Kilimanjaro in 1992, now thriving (at last) in the new greenhouse at Myddelton House.