Winterizing Raised Vegetable Beds
I am just looking for some suggestions on how to regenerate soil in our raised vegetable gardens over the winter. In the past I have just tilled the soil, added mulched leaves, and added new soil/manure around the time of planting in the spring. I also send out soil samples to be assessed for nutrients before I plant as well. The vegetable beds are predominantly for tomatoes, onions, and asparagus.
Your practices to improve the soil sound good. The best option is to add compost to the soil. After a few years of large additions you can decrease the amount to 1 in. each year. It takes 8 cubic feet of compost to cover a 100 sq. ft. garden to a depth of one inch. The goal is to have organic matter comprise 25 to 30% of the top 8 inches of soil by volume. Do not apply un-composted manure after crops are established. Fall application and incorporation is recommended for home gardeners. Here is more information on organic matter and compost http://extension.umd.edu/hgic/plants/prepare-your-soil
Keep your garden soil covered as much as possible throughout the year and winter (shredded leaves) to prevent soil erosion and nutrient run-off, and keep weed seeds from germinating.
Next fall you can plant a cover crop to add nutrients to the soil and prevent erosion. http://extension.umd.edu/hgic/cover-crops-protect-and-improve-your-soil
Also, take a look at our website for the vegetable crops you are growing http://extension.umd.edu/hgic/plants/vegetable-crops