Seiont owner Neil Alcock explained: "They are winding down their business and we are taking over their Rhododendron and Azalea. We are already established as Rhododendron growers in our range, but they are specialists.
"Nothing formal has happened, but Woodland Barn is happy that we are taking on its ranges and we will be contacting customers soon to tell them that we will be taking them on."
He added: "It would be a shame to lose a range like that because they have worked hard on it for the past 15 years, and it fits nicely into our offering."
He explained: "We are taking in the first cultivars next year and the first batch will be ready in spring 2012, but in the interim we are increasing our range of Rhododendron because they have increased in popularity.
"We have seen a big rise in demand with these plants, probably because Woodland Barn was winding down, so it fits into our range quite nicely."
He added: "At the moment most of the mainstream garden centres will only buy ready-grown Rhododendron, but the market we are looking for is grow retailers and smaller wholesalers. We are committed to fulfilling the regular deliveries to smaller customers."
Commenting on the business as a whole, he said: "At the moment we are increasing - we had a good year this year and we finished about 10 per cent up on sales on last year, though we are still down on price pressure.
"I like that we are always moving forward - we can never stand still and we need to constantly look to improve what we do."