They planted a mixture of deciduous trees donated by the company in Dunorlan Park in Tunbridge Wells, Kent to support the horticultural charity. Sodehxo holds the grounds maintenance contract with Tunbridge Wells Council to look after the park.
The trees are on sale for £20 each via the Perennial website and all the money will be donated to help horticulturalists in need. The buyers see their names added to a commemorative plaque in the park.
Sodexho operations director Nigel Payne said: "We had a fantastic turn out for the Perennial Woodland Garden planting yesterday and we are all proud to be supporting the work of a unique UK charity by giving something back to the community in Tunbridge Wells.
"Perennial plays an important role in supporting those who look after the UK’s green municipal spaces, as well as all those working in or retired from horticulture, so it seems fitting that we should enhance this wonderful park with a new woodland garden for visitors to enjoy for years to come."
Perennial’s president, Alan Titchmarsh said the woodland garden was "a wonderful way to raise money for Perennial while further greening the environment for future generations."
He added: "We are looking to our colleagues across the horticulture industry this year to support the work of our great charity with fundraising challenges, pledges and donations."
Perennial has set a target to raise £175,000 this year to mark 175 years since it was founded.