Comfrey. This plant is an amazing helper in the garden. It is an excellent organic fertilizer, a compost accelerator, pollination center for bees and well why not its a medicinal.
We have five raised beds, about 20 grow bags and various squashes planted in ground along with the expected raspberries and strawberries. And a side project growing a grove of elderberry bushes. Coming this spring building my wife a greenhouse.
All are fertilized with only comfrey used in various ways depending on where its being used. We make a liquid comfrey fertilizer by soaking the leaves in a bucket of water for a couple weeks. We use the leavers straight from the plant and lay them directly on the ground around the other veggie plants for mulch and fertilizer together. In the fall when closing up the beds we lay comfrey leave on the ground, cover with soil to ready the beds for the spring.
I also grow organic cannabis inside in a grow tent. To fertilize inside, I chop up the comfrey leaves, dry them and use the resulting crumble as a side dressing.
In addition to all that of course it adds biomass to the beds and compost pile. If you go to purchase comfrey make positively sure you get the Russian strain, its not the invasive kind.
https://www.tenthacrefarm.com/what-is-comfrey-and-how-to-grow-it/
https://www.masterclass.com/articles/comfrey-plant-guide
Did you know milk is beneficial in the garden?
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/milk-fertilizer.htm