In the fall, you can let all the plants die back and let them sit over the winter. The exception is to remove any diseased plant material and throw it away in the trash. Do not compost. While compost does heat up due to bacterial action, many home composts don’t reach 160F needed to kill pathogens.
In springtime, there are two things that you need to do that will help you have a very successful upcoming second year.
First, amend the soil. The plants from last year took nutrients out of the soil. You will need to replace them. One of the best ways to do this is to add compost. This can be store bought or your homemade compost from your kitchen scraps, grass clipping, and leaves. Second, you only need to layer it on top. You no longer need to till the soil. Doing so is now considered to be detrimental to soil health and growsmore weeds. Hard to believe, but the science is there. Save your back, and you save the soil!
Second, practice crop rotation. Don’t plant the same plants in the same place, year after year. Crop rotation keeps diseases and insects at bay by disrupting their life cycles, improves the soil structure because different plants have different root structures, and different plants have different nutrient needs. It’s about balance. And how do you know what not to plant in the same place? By reading your garden journal from last year!
Finally, gardening will always be trial and error and at the mercy of Mother Nature. However you can have a very successful raised bed garden. You need to have a plan, meet the plants needs, watch the weather, and keep notes. It may seem like a lot, but eating food you grew is worth it.