His pyramid, or tower, sponsored by Westland Horticulture, is a piece of work. It stands 80ft tall, with a scaffolding frame, and has seven floors altogether, which each have a different theme. On the first floor is a miniature gentlemen's clubroom, looking out onto a Japanese terrace. The second floor has flowers - peonies and roses - while the next floor has a greenhouse, a cold frame and a vegetable patch, grown in raised beds.
There is none of the meticulous finish you find at Chelsea - the floors are made of scaffolding boards with rather alarming gaps in between, and there is a very random selection of furniture, ranging from swing seats to Adirondack chairs.
A lift - of the most basic kind - takes you up to the sixth level, thank goodenss, because although there are stairs up to the first floor, further access is by ladder. Erk! I'm terrified of heights, so I went up in the lift, stood on the sixth level (with my legs shaking) long enough to take some pictures, and came down in the lift, feeling rather sick and looking rather pale.
VP, on the other hand, came down the stainless steel flume - like the ones they have at water parks - which runs from the top to the bottom. She said it was fab. I'm quite happy to take her word for it, and I'm full of admiration. As it was, I had to go and have one of Mark Diacono's cocktails afterwards to make me feel better (he was acting as bartender on Jo Thompson's Caravan Garden).
The great man himself.
Sculpture and planting on the ground floor
A seating area on the first level
Looking up through the lift-shaft
The gentlemen's club on the first level, which looks out onto a small Japanese-inspired balcony
A miniature pond complete with water lilies
Arriving on the ground floor by flume
The view of the showground from the top of the tower. This was taken quite early, about 9am, so it was still fairly hazy. Still, I'm glad we went up then - we just wandered on, whereas later in the day, there were huge queues of hacks.
Looking down from the sixth level at the vegetable garden
The view of the Thames, and Battersea Park, to the south.
There has been a bit of controversy about Diarmuid's garden (no!) because there was some suggestion that he was going to let the public on, in defiance of health and safety rules. The RHS line is that if he chooses to invite people on, and they want to go, that's fine, but it's totally impractical for the public to have access. If you think the RHS might take rather a pompous attitude to Diarmuid's tower, then let me tell you that head press officer Hayley Monckton has already been down the flume.