A garden trowel is a small hand tool with a pointed, scoop-shaped metal blade used for digging, scooping, and planting in the garden. On the other hand, a garden transplanter is a specialized tool with a long, narrow blade designed for digging small holes for transplanting seedlings or small plants. The main difference between the two is that a trowel is more versatile for general gardening tasks, while a transplanter is specifically designed for transplanting tasks.