When I complained about back ache from weeding, doc said get a gardener. That is bad answer for bad times. Can you help?

Exercise. Your doc may know more about your personality than your complaint conveys. Gardening requires stooping and bending and puts strain on the back especially if you do a lot of lifting. If you do this after a long period of inactivity, you could get back strain. You might consider attending a gym, doing yoga, gradually increasing exercise and stretches. You will need patience and diligence.