Plant Doctor Archive

Comfrey and Yarrow

I KNOW that comfrey and yarrow (right) can be added to the compost heap to speed up the breakdown process, but how much do you need to add - and how often? Also, do you have any idea of ratios of comfrey to seaweed if making a liquid fertilizer? And does it need to be diluted?

COMFREY has a high protein and potash content. The leaves can be cut, allowed to wilt and then put in trenches before planting crops such as potatoes. Or you can make them into a liquid fertiliser by soaking the chopped leaves in a bucket of water for at least a week. The liquid can then be watered directly onto the compost heap as new layers are added, or diluted down to the colour of light tea and watered occasionally onto crops that like potash, such as potatoes, tomatoes, peppers and fruit trees.

Yarrow also has the ability to concentrate copper, phosphates and potash from the soil. Its leaves can be used in a similar way to those of comfrey.

Both comfrey and yarrow have the ability to activate compost heaps. Any leaves added to the heap will help speed up the production of loam. When making a liquid fertiliser of seaweed, add as much yarrow and comfrey as you can gather. Soak well for several weeks and apply at the strength of weak tea.

Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.