I last saw John Cushnie in mid-December recording a special Christmas edition of Gardeners' Question Time (GQT) at The Museum of Gardening History in Lambeth Palace.
He was well - and in full flow. He was a handsome man and a very big presence. There was no sign at all of anything wrong - so his death on New Year's Eve comes as a very big and unwelcome shock.
GQT has an alchemy. It is not merely a programme of gardening experts about trees and plants. That is the core of the matter - but it is also about character and wit. And John Cushnie had those qualities in abundance. He did not do vanilla. His answers - delivered in that instantly recognisable Northern Ireland brogue - were, of course, always informed - but they were laced with acerbic wit and warmth. He spread joy during the programme recordings - a joy which was transmitted to the audience at home.
And thus it was during that particular recording. John was asked to sum up the 2009 gardening weather in Northern Ireland. He immediately went into a fluent riff about the unfortunate timing of the hot spells, wet spells and dry spells. Everything had come at precisely the wrong moment. Potatoes had been a calamity - but he had managed to grow a few things successfully even so. As per normal everyone was laughing.
Then someone from the audience produced a sample in a plastic bag of a plant that she wanted to preserve. John was apoplectic - about the state of the plant - and his advice was trenchant - along the lines of "Get rid of it - now. Entirely. Forever. Awful." This was a common Cushnie response to a plant specimen - or even genus - that aroused his ire. And there were quite a few of those...
All the banter ('crack' seems the right word for John) was never at the expense of the knowledge. He knew a tremendous amount about a tremendous amount of horticultural life and that showed too.
We will miss him a great deal.
Mark Damazer is Controller of BBC Radio 4