Here's another blog by a Milton chiropractor discussing: Common gardening injuries.
Quite often when gardening, it's easy to get so involved in the task that you forget how long you are working as you just want to get the work done. The repetitive bending, lifting, digging and weeding can result in overuse injuries.
Try to remember to break up tasks so that you're not repetitively lifting or bending, and alternate light with heavy tasks every 15mins. Take frequent breaks and stay hydrated, and always use proper lifting techniques.
Gardening is physical work, and like any other physical activity, to reduce your chanced of injury, you should warm up before starting, as well as after your work is done.
For more information on specific stretches, please see the following article
Dr. Amanda Lett, BSc(Hons), DC