If you have the space, gardening is a great compliment to a rubbish free lifestyle. It soaks up all the compost you can produce, is cheap, good exercise, and is the epitome of local!
When getting setup try and buy quality, non plastic tools (including handles), that way if they break they can be dismantled and recycled. If they are too expensive at the store, consider purchasing them second hand. This way you can get really good quality at about the same price you’d pay for some cheap tools.
Plan ahead and store or buy seeds, this avoids buying plastic seedling trays. Sometimes seedlings are available in wrapped-up newspaper or old milk cartons.
Try gardening without commercial pesticides, etc. There are plenty of effective home made equivalents - ask at garden centers, the library, or do some web searching. Megan from Christchurch suggests a great insect spray can be made easily with, "... 2 1/4 litres of vinegar mixed with 1/2 cup salt and 1/2 Tablespoon of dishwash liquid. Spray directly onto weeds or vegies being nibbled! Better than the idea of rhubarb leaves boiled, which I think could be toxic to humans??!!"
We used some old carpet we had as weed mat. You just need to make sure it is wool and not a blend as nylon won’t break down. It is great if you are going to build raised vege gardens as well and it slowly degrades over time.