Beautiful chair pad. There's no link for a pattern, but you could figure this out from a granny square-type pattern. I think big, chunky yarn and maybe several strands together - should be easy enough to make!
Pin Cushion Roundup
Quick Easy Cacti by Lucille Randall pattern published in Simply Knitting Summer 2013 (#109). Purchase print, digital (£2.99) or zino at http://simplyknitting.themakingspot.com/shop