Lawn care is made easier with flat trim next to your gardens that the lawn mower can roll over. This also helps to keep the weed-whacker away from your plants.
For sporadic planting of taller plants, (which makes them more susceptible to windy weather than grouped plants), use tomato cages to keep them upright. A cage will also keep plants protected from the occasional animal that wants to lie on them!
Save milk jugs and cut out the bottoms to use in the early spring garden. You can use them as mini-greenhouses to give plants an earlier start. They also provide protection from the bunnies to tender young plants until the plants are more mature. A small slit in the side makes staking them and moving the container to the side during the day easier. Remove the container, or the lid, during the day (don't cook your plants!) and replace it in the late afternoon to store warmth for the evening.
As part of preparing the garden for winter when freezing weather starts to approach, make sure to disconnect the garden hose from the house and drain the hose. Leaving the hose connected can cause damage to your hose, but worse yet -- it opens you up to the potential of a burst pipe.
Putting your container gardens on wheels can come in handy. It will save your back when you want to move containers to a protected area during severe weather or when you know you will be gone for a few days and want to keep your plants out of the hot sun.