Comfrey -- I'd like to try growing this to use for mulch -- see articles

 But where to put it... so little space and this thing takes over...

https://www.permaculturenews.org/2016/06/03/comfrey-believe-the-hype/?fbclid=IwAR08QKJlLJP-xduLrNoIJZ4J_MqhaBMGsvqa2Ef4HnfWfy5sbaRxUsfKUnk

https://www.growveg.com/guides/grow-your-own-fertilizer-using-comfrey/#:~:text=What%20is%20brilliant%20about%20comfrey,feeds%20for%20concentration%20of%20nutrients.