That's Comfrey makes a good plant food ,put Comfrey in a bucket and cover it with water then let it steep for 10 days then use the liquor to feed plants ,I use to use 1 pint liquor to 10 gallons of water for a quick weekly feed want it stronger less water,also add Comfrey to a compost heap cover heap and stand back ,I use to mow a lawn on a Friday and layer the grass cuttings up with Comfrey leaves 7 barrow loads went in to the compost bin ,it would be level to the top of the wire 6 feet, covered with a sheet the following Tuesday the sheet had to be replaced it got that hot ii melted ,80 to 90 degrees in the centre of the heap