The fourth series of the show, produced by Spun Gold Productions and fronted by Alan Titchmarsh, begins filming in the spring.
Frosts will design and build gardens which meet the individual requirements of eight chosen families, with the aim of bringing joy to those in need.
Frosts hopes the extra publicity will drive trade to its garden centres and garden design business.
Managing director Ken White praised Titchmarsh for his tireless "passion and support for the industry".
He added: "This will be the group’s first venture in to the exciting world of television with its unique set of challenges."
Executive producer at Spun Gold, Matt Young said Frosts was one of the best landscape contractors in the business.
"When we met Ken and his team they impressed us immediately with their professionalism, enthusiasm and attention to detail. As Love Your Garden continues to go from strength to strength we look forward to working with them on what we hope will be our best series yet."
The Outdoor Room worked on the first three series of Love Your Garden but pulled out in October.
Managing director David Dodd criticised the show’s format but Young said the show had "a genuine mission statement" which helped people with limited happiness in their lives.