A handy garden tool is a collapsible bag that can be folded down and stored easily. When you need it, pop it open and it stands on its own. It's great for loading up leaves and debris, and has a large capacity. Made of heavy vinyl, it also resists rips and tears, so you don't have to worry about it splitting like a regular plastic garbage bag. Better still, it's mildew resistant -- because the last thing you want to use is a bag that introduces germs into your clean garden!
Kneepads are very helpful in the garden because they make working on the ground more comfortable. Good-quality kneepads have a hard outer shell to keep out water and prevent sticks and stones from poking through to your knees. They should also have heavy-duty foam inserts to keep your knees comfortable for hours of kneeling. Some kinds have elastic straps that hold them in place, even when you get up and walk around. Be sure to try on any kneepads you buy before you leave the store to make sure the size fits you comfortably.
Another product for kneeling in the garden is a double-duty bench. On one side, it's a kneeling pad that you can use when you need to get close to the ground for planting, weeding and harvesting. You just put it down with the handles facing up. The handles make it easier to get up, especially if you've been kneeling for a long time. The other way to use the bench is as a stool -- just turn the handles down and they become legs. You can sit on it to cut flowers or harvest mid-sized vegetables like okra or tomatoes. The foam insert makes this product comfortable for sitting down or kneeling.