Making comfrey juice in a barrel

We needed more comfrey juice for the tomatoes and courgettes so a bigger press was necessary. Having located an old plastic barrel production was about to be upgraded by about 450%

The only free level spot in the garden to site the new comfrey juice factory was next to the water storage tanks. The ground was prepared ready for the tank.

First the top of the tank was cut off with a standard wood saw. Next a hole was drilled as close to the bottom as possible and a short length of garden hose was pushed in and sealed with mastic. The was filled tank with around four very full wheelbarrows of Comfrey and the weights were added – a paving slab and several stone bricks. All that remained was to put on the lid to keep out rain and see if it works!

Today I checked the container and found 2.2 litres of rich, black comfrey juice! That has taken just 8 days. The juice was dripping out of the tube every 5-7 seconds. The small sewer pipe press has not produced anything yet.

Production updates
15/07/08 – Filled
23/07/08 – 2.2L Total 2.2L 8 days
24/07/08 – 1.1L Total 3.3L 9 days
25/07/08 – 1.2L Total 4.5L 10 days
28/07/08 – 3.4L Total 7.9L 13 days (After long weekend away)
30/07/08 – 1.1L Total 9.0L 15 days (Output slowing now)
09/08/08 – 3.6L Total 12.6L 25 days
17/08/08 – 1.5L Total 14.1L 33 days (The barrel was emptied and refilled)


  • The total of 14.1L will be diluted 1:10 with water to make over 150 litres of tomato feed.
  • The plants used for the first harvest had regrown sufficiently to be used for the second filling of the barrel.
  • It should be possible to get a continuous supply using two barrels, with the second filled 15 days after the first.

This has been a very successful project and something that will be a permanent feature in the garden. It has certainly helped to make the garden more self-sufficient in nutrients which has always been my long term aim.

2nd Batch
17/08/08 – Filled
23/08/08 – 1.6L Total 1.6L 6 days
26/08/08 – 8.0L Total 9.6L1 9 days
30/08/08 – 6.0L Total 15.6L 13 days

1. The barrel was filled with new leaves which seem to work better!

Update 09 Apr 2009
The second barrel is installed and waiting to be filled. I plan to be using the liquid from one barrel as the other one is filled. That should provide a continuous supply of comfrey liquid which is especially useful in the tomato growing season.

22 June 2009
The first barrel was filled about 3 weeks ago and has produced 15 litres of liquid so far. I plan to fill barrel #2 to maintain supplies for the soft fruit, top fruit, courgettes, tomatoes and the potatoes growing in a dustbin.

01 July 2009
Barrel #1 produced around 17ltrs of juice and barrel #2 has given 2.5 litres since filling on 22 June.

Updated 27 May 2019