A picture is worth a thousand words and can extol the greatness of compost.
This plant, a sweetie cherry tomato, was started from seed in late-March and was planted outside on the May long weekend - about one month ago. While it wasn't planted in soil amended with compost per say, it was planted where the old compost bin used to rest. We had to get rid of the bin this spring because it was cracked, split open and no longer composting well.
The tomato plant sits there and soaks up the compost goodness day after day. It has outgrown all the other tomato plants in my garden.
See the brandywine tomato in the background that looks paltry in comparison? It's not that small. Nor, is it not a sight to see. But, whoa. Look at that tomato plant.