[icemann427]

You can purchase premixed bags of concrete at Home Depot, Lowes, or places like that. I think they weigh about 80 lbs each and cost about $4.00 per bag for the 4,000 lb stuff. Just add water and mix it up with a shovel in a wheel barrow next to where you will be working until you have a good consistent mixture and pour in the hole. One yard of concrete is good for 98 square feet when the depth is 3.5" so you won't need much if you only have 3 square feet...Maybe two to three bags give or take.