by Norman Green

Created on: January 01, 2011   Last Updated: May 29, 2011

'Comfrey tea' is an organic liquid fertilizer which can be easily made at home by even the most inexperienced gardener.

Comfrey ( Symphytum officinale), is a large hairy leaved perennial, a member of the Borage family. The large leaves are high in nitrogen and other vital elements, including potassium, which are essential for healthy plant growth. The plants posses deep taproots which means nutrients are drawn up from deep in the soil. The plants will grow into large clumps, but do require dampish conditions.  Set aside a small corner of the garden just to grow comfrey. It is an impressive looking plant, and when in flower attracts a multitude of beneficial insects. This is all good for the garden, even before we come to its use as a fertilizer.

From the beginning of May, when there is plenty of fairly large leaved new growth, simply break off leaves and put them into a plastic builders bucket. These buckets hold 3 gallons, but only half fill them with leaves. Don't entirely strip a plant of leaves as this allows them to recover more quickly and so you can have a continuous harvest of leaves for the rest of the summer. It should be noted that the leaves are rather coarse and hairy and so gloves should be worn.

Now fill your bucket up to the halfway mark with water. Tap water or collected rainwater can be used for this, each with excellent results. To weight the comfrey leaves down use another bucket. This bucket has holes drilled in the bottom. When placed into the first bucket and half a housebrick added, the comfrey is compressed but the water you have put in can rise through the holes in the second bucket. This compression seems to speed up the process whereby the comfrey leaves begin to rot and then leach their goodness into the water. Basically you are making a cold infusion of comfrey leaves, which is where the phrase 'comfrey tea' comes from. Leave the bucket to stand, somewhere out of the way.

As long as the weather is not too cold, the tea can be ready to use within a couple of weeks. Remove the top bucket,letting the liquid drain as you do. You should have already become aware of the smell of this wonderfully dark green soup. The best way to describe it is that of an open sewer or cesspit. Well rotted compost can smell sweet, this does not! This soup will contain partly rotted leaves and also green sludge and so needs to be strained. This residue can be thrown on the compost pile or added directly to the soil underneath plants that need feeding. The remaining liquid is decanted into 2litre plastic bottles and stored out of direct sunlight.

As to usage, the advice is little and often. Always dilute the feed, putting a dash into a watering can before adding the water to ensure a good mix. It works well on greenhouse crops such as tomatoes and peppers, with excellent results. It can be used on flowers and plants in borders and containers as well. Use it for houseplants, but very well diluted due to the smell! A very dilute mixture can be sprayed onto plants as a foliar feed, to give them an instant boost. It is well worth the effort to make several batches throughout the year, and after a while you even get used to the smell!

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