If you feed
plants with compost, it will do well. Better than it would without it. (Unless it's a cacti maybe.)
You feed the soil organic matter and let the
plants take what they need. To do this, you build humus in the soil. That fine broken down layer that occurs between mulch and soil. That's the good stuff. If you build healthy rich deep soil, you've fed your
plants. Then all they need is water.
So mulch, minimise chemical use, encourage earthworm activity, and add compost and more mulch. Lucerne/alfalfa, green manure crops, animal manures, fish and seaweed extracts etc. These things all feed the soil organically, slowly releasing their nutrient at a rate that somehow just happens to be the right rate for your
plants.