Thank you for your question. I would suggest you contact Winona County Extension to answer your question about compost and if the Master Gardeners have a garden you can visit. Here is a link to more information, including a Master Gardener contact:

https://extension.umn.edu/local/winona

The University of Minnesota offers a mail-in soil test that provides valuable information. Here is a link to more details about soil testing:

https://extension.umn.edu/managing-soil-and-nutrients/soil-testing-lawns-and-gardens

Happy Gardening!