Home Depot typically starts selling Christmas trees in early November, though the exact date can vary depending on the store's location and inventory. Some stores may begin selling trees as early as October, so it's always a good idea to check with your local Home Depot store to see when they start selling Christmas trees. Additionally, some stores may offer pre-ordered trees that can be picked up closer to Christmas. So, if you're looking for a specific type of tree or size, it's best to check with your local store to see when they have them available.