compost or soil
I have built a 12" border around my existing Vegetable garden. I need to add at least 5" of either compost or soil. I was going to use commercial compost, if this is right when should I add it now in the Fall or wait until the Spring.
Certified GKH Gardening Expert
It would not hurt to add a little of both, but if you had to choose, then compost would be more beneficial. I like to add in the fall to give it time to break down a little in the soil.
This article will give you a little more information on the benefits of using compost: https://www.gardeningknowhow.com/composting/basics/garden-compost-benefits.htm