Templar was Homebase plant buying manager. Owners Wesfarmers confirmed her departure this week. Other senior garden management staff are also believed to have gone.
Paul Emslie moved to Wyevale Garden Centres as trading and marketing director this month having been commercial director at Homebase.
Wesfarmers bought Homebase in January for £340m. Many directors of Homebase, including managing director Echo Lu, have since left.
Wesfarmers said it will announce further plans for Homebase this month.