Dobbies Garden World in Ashford, at Eureka Leisure Park, opens in the first week of March.
The £8m, 5,000sqm Dobbies will offer more than 10,000 plants and a specialist aquatics department.
The Ashford centre will also house a Farm Foodhall offering locally-grown produce from Kent and the surrounding area, as well as a restaurant.
Some 120 new jobs have been created.
Dobbies caused controversy when it unveiled plans for the centre because it is close to the existing Bybrook Barn garden centre in the Kent town.