The Manchester centre celebrates 40 years in existence this year and marketing manager Jill Somerville said Hills had been a target to "expand the empire" for a number of years.
Financial director Jason Stafford said:
"It has been our intention for some time to expand the All-In-One business with an additional site, Hills Garden Centre is the perfect opportunity to develop and strengthen our business further. Our primary focus will be to work with the current teams and develop the site to the high standards All-In-One is known for whilst offering customers a first class shopping experience.
"The board of directors would like to acknowledge the hard work the Hills Garden Centre staff has achieved in maintaining the high standards of garden retailing over the past two years".
"The new site will be re-branded as All-In-One Garden Centre, as quickly as possible. This initial investment will continue with the implementation of and upgrade of the IT systems and customer facilities.
"The current Hills Garden Centre staff have been briefed and introduced to part of the All-In-One Garden Centre personnel. A full induction and training programme will take place to ensure a smooth transition and welcome them to the All-In-One family."