When picking vegetables I either sit on a bucket or get on my knees. These knee pads have worked great for me. I don't know what kind they are. I would guess soccer. I found them in the sports section at Walmart about 3 or 4 years ago. They are padded well and have a hard plastic shell on the outside to protect the knee. That shell has kept them from wearing out.
When the ground is damp, the knee pads can become quite dirty. I just hose them off and lay them out in the sun to dry.
This page contains the following solutions.
Make a pair of gardening pants out of an old pair of jeans. Sew the pockets from a pair of old pants on the knees of a pair of jeans. Then stuff the pockets with some foam rubber. These built in knee pads really save your knees. Just remove the foam rubber when you wash the pants.
To protect your knees when gardening, sew patch pockets on the knee area of your pants. Slip sponges or soft foam into the pocket.
This is a page about homemade garden knee pads. Spending hours working in your garden can be very rewarding, but it can also be hard on your knees.
