The Nottingham-based company runs seven retail websites, with the main one available at www.internet gardener.co.uk.
Internet Gardener has relocated to new 730sq m larger offices in Calverton that feature warehousing and a showroom.
Director Sue Baxter said: "We feel having a showroom will give our customers the opportunity to view the higher-value furniture and top-of-the-range barbecues, all from leading suppliers.
"The larger offices allow us to increase our customer service department. As we encourage customers to call us, we invest heavily in product training and so have a very knowledgeable team.
"Our in-house web development and accounts teams now have more space to expand. Our warehouse expansion allow us to increase our ranges."
She added that in recession wealthier customers carry on spending and they want to see working outdoor kitchens that are often not available in garden centres.
Sue's son Andy founded the business in 2006 after working at a garden centre that did not take up his idea to set up a sales website.
The company now employs 11 people and sells 10,000 different products. The new building will open in February 2013.