How to make homemade fertiliser, 4 simple steps

Comfrey leaves have extra deep roots, meaning they are able to extract nutrients from the soil that other plants can’t reach. These nutrients are stored in the leaves, which can then be harvested to create a potassium-rich feed. Liquid fertilisers provide instant nourishment for plants as the nutrients are quickly absorbed by the roots.

• Gardening gloves

• A large bucket with a lid

• A brick or heavy stone 

• A (recycled) plastic or glass bottle 

• A watering can

Remove leaves from the lower section of established comfrey plants. We recommend wearing gloves to protect your skin from hairy leaves, which can cause irritation. Cut off any tough stems and remove flowers – that you can then add to the compost heap. 

Chop or tear the comfrey leaves into smaller sections and place as many as you can fit into a large bucket. Use a brick or large stone to weigh down the leaves, then cover with a lid – the leaves can release a strong odour as they decompose.

The leaves will break down gradually, releasing a brown liquid. Check on the progress of your feed every few weeks and top up with fresh leaves as required. Collect any liquid and store in a cool, dark place.

Dilute with one part liquid to ten parts water. Pour the diluted solution into a watering can and fertilise your plants – great for your garden and the planet.

You can also use comfrey leaves to make a mulch for tomato plants. Simply spread fresh comfrey leaves around the base of the crop. As the leaves decompose, they will provide essential nutrients, supress weeds and help to retain moisture.