Here is some green goo. I've been brewing a big vat of Comfrey tea. Frankly it stinks but is said to be an excellent fertiliser that is high in NPK i.e. nitrogen, phosphorous and potassium. 

 Comfrey pops up all over the place on the allotment. I let it flower for the bees then cut it back and add it to the pot. In fact it keeps growing through the summer months as a cut and come again crop.

 The theory is that Comfrey is a "dynamic accumulator" because the deep tap roots gather up minerals and nutrients which are released by steeping the leaves. I add the stems as well though the concentrations are probably higher in the leaves.

 I've held off using it while the soil has been so dry but yesterday we actually had some rain. And the right kind too- steady persistent drizzle which soaked into the parched ground making it more receptive to a liquid feed of this stinky brew.