Why type of footings do I need for stone wall around my flower garden?

Dig a trench 9" below ground level and back-fill it with 6" concrete,your concrete is now 3" below ground level and make it 2' wide and centre your wall in the centre of the footing build up your block work wall 9" wide and leave some wire mesh strips hang out of the mortar joints these will act as fasteners for your stone wall and keep both the stone and block work tied together when mixing your concrete try to use a minimal amount of water so when cold weather does arrive the less water in concrete would mean that it has less chance or cracking as water expands when frozen and this then leads to cracking in the concrete.