He said the show had "gone through a renaissance" and brought a lot of kudos to brands. Designers Harry and David Rich brought good PR and the show gave a great opportunity to engage with customers, he added.
The Rich brothers are sons of ex-Vital Earth commercial director Malcolm Rich, whose company Rich & Sons built the garden.
Twitter followers trebled and, after communicating well to the trade, the show kicked off communications with consumers.
All of the plants were supplied by Dingles. Harper said local sourcing of plants and a peat-free Chelsea compost mix were at the forefront of the garden.
"I can't believe people go all over the world to get trees when you can get them locally," he added.
After winning a Gold Medal for a small garden at Chelsea in 2013, Harper said he made sure Vital Earth was included in the garden title this year.