This week his wife Denise, who writes the Gazette’s farming column, spoke warmly about her husband who had farming in his blood and was the sort of man who would do anything for anyone.
The family have asked for men to wear bright ties and women to put on colourful hats for the service which starts at 2.30pm and is open to anyone who knew the dedicated farmer who was out on the combine harvester on the day he died.
Mr Plummer, who died aged 69, moved to Wiltshire as a boy when his family took over Leaze Farm, Stanton St Quintin, between Chippenham and Malmesbury.
Mrs Plummer said: “He always loved farming and really enjoyed his life. On the day he died he had been out on the combine. In the past months we had been away on trips and he had seen a lot of friends.
“We both came from a farming background and met when we at agriculture college in Devon. Back then he was much more out going than me and I was a little bit in awe of him but we had a lot in common.
“We married in 1972 when we were both aged 22. It is a mixed dairy and arable farm but Richard always said that he preferred the crop side of farming. He loved the soil.
“I had always been horsey and Richard became very involved with them too. He was a steward at shows.”
A proud moment came in the 1990s when the couple went to Wembley with a horse in the Working Hunter Pony class at the Horse of Year Show and took fourth place.
The couple went on to have daughters Adele and Melissa and four grandchildren Dominic, Bethany, Natasha and Annabel.
Mr Plummer had suffered from health problems for a number of years but his death came as a terrible shock to the family.
His wife said: “We had been planning to go to Australia in September. He will be badly missed by a lot of people as he was such a big character and so kind.
“He was the sort of person who really would do anything for anyone. If he saw a pile of cuttings by the side of the road when he was out on the tractor he would just think ‘oh they need getting rid of’ and stop and put them in the trailer.
“He was a very outgoing man who had time for everyone. He worked very hard and enjoyed life to the full. I have been overwhelmed by the messages of support I have received.”
Donations for the Royal Agricultural Benevolent Institution and the Wiltshire Air Ambulance will be taken at the thanksgiving service.