Managing director Peter McDermott said: "This is a good development for us. We're forward planning and this gives us sustainability.
"Our current site has met our needs for the last few years but as a business we felt it was time to look for a site that we can develop for our own specific needs and a site that allows us to deliver growth we anticipate in the next 3-5 years."
Kingfisher will trade through this season. Kingfisher went up for sale in late 2015 to allow the owners to retire.
YouGarden will use the site for some growing but mainly for plant care by its customer operations team, as it does at its existing rented premises at Deeping Gate Trees, which are likely to be taken over by the other tenant on site.
McDermott said he hopes to be up and running by the end of this year.
He said recent news of the success of Thompson & Morgan and Suttons was good for the direct marketing industry.