Retail seeds and marketing director Ramsden has been at Suttons for 10 years. He will move on March 1.
His role at Hozelock will be as account manager for B&Q, Wickes and other multiple retailers.
Hilary Mabbutt will become Suttons sales and marketing director.
Ramsden is GIMA vice president.
Meanwhile, Suttons has launched a Cancer Research Uk charity range of £2.50 per pack seeds. A donation of 25p a pack goes to the charity. The range includes 68 vegetable and flower seed varieties.
Suttons are now also working with Hedges Direct.