if your wife can't squat, then are you suggesting that she sit on the ground or kneel? instead, how about sitting on a bucket with a caddy apron and a seat - it doesn't weigh much including all the tools she'd need. and long-reach tools work for many garden chores

I have a nice gadget my mother gave me several years ago, and I've since seen similar things in catalogs. It's a combination seat/kneeler. Flipped over with the legs pointing up, it's a padded kneeler and you can use the legs to brace yourself when getting back up. With the legs down, it's a seat. I have a bad back and bad knees, so squatting doesn't work for me, either and this stool is very handy. The only drawback is its size. Sometimes I can't use it because I'm working in a small space.