Ventnor Botanic Garden said goodbye to "a truly remarkable person" last Friday, and made sure the former garden supervisor, volunteer mentor and student mentor started her retirement in style.

Trish Brenchley drove her tractor, which colleagues had decked out in balloons and tin cans, past her long-nurtured mixed flower border to the courtyard where her fellow gardeners, friends, volunteers and former students awaited her with cheers – followed by speeches and lunch in the Edulis restaurant.

Trish has worked at the garden since 1988 as a gardener and garden supervisor.

In addition to organising the gardeners, she looked after the many regular volunteers, special needs groups and students.

After a break of a few years Trish was brought back by the Friends' Society to train and mentor a succession of horticultural students in conjunction with the IW College.

In his speech, Chris Kidd, VBG's curator, pointed out that her job titles do nothing to explain the sheer scale of what she has achieved.

"Think about the changes that have happened since 1988. The olive grove was just covered in poor trees, the Mediterranean garden wasn't much to talk about and this courtyard was a rose garden. The nurseries were a fraction of their current size."

He amused the guests by saying he and Trish hadn't at first got on, but their different approaches were smoothed out because of their shared love of the garden.

"We both agreed the garden needed change, so I developed it and Trish looked after it afterwards."

Chris praised Trish's ability with people. "What she's done beyond the horticulture is extraordinary too. The training that has gone on in this garden. Students have gone on to [RHS Garden] Kew, to [RHS Garden] Wisley, to Sparsholt College.

"People have done better things with their lives directly as a result of the pastoral care and passion that Trish has put into them. That's not something that you can learn, this is something innate, and comes from within."

He said the garden is looking better as a result of the maintenance that Trish has put in than at any time ever since 1972.

Trish had written a letter to the Friends' Society of VBG, thanking them for the generous funding they had given the garden over the years.

She added: "We have come a long way, especially over the last few years, as we've made a concerted effort to restore the garden to its former glory and beyond. This place is looking good."

Two of Trish's horticultural students returned to join her send-off. Ellis Gant is currently a Diploma Student at RHS Wisley, and Adam Cooke gardens with his family's firm.

Other success stories include David Pearce, who became gardener for King Charles's estate, Highgrove, then head gardener at Whatley Manor and is now curator at Abbotsbury sub-tropical gardens, and Indi Wyatt, a diploma student at RHS Kew.

Ellis said: "Having Trish as a mentor during my apprenticeship at Ventnor was a fantastic experience – her tenacity to do the best possible job was inspiring."