Introduction: Making Liquid Fertilizer From Weeds

About: I am a Marine Engineer in the RNZN (45 years done in various navies) and am looking forward to retirement!!! so I can do more messing about with tools

Weeds, we've all got them!

Let's turn them into something useful.

Now I don't like putting weeds into my compost heap as you can end up with them spreading, the alternative is usually to burn them but they are full of nutrients so this is a bit of a waste.

Why not try to recover the nutrients and at the same time render the seeds from the weeds inert.

All you need for this is:-

A Container (in my case I have used a plastic 45 gallon barrel)

Weeds (no shortage of those!)


I have actually looked iat some past I'bles since publishing and refer you to tim_n nettle fertiliser from 2010 i hadn't realised however it does give me the opportunity to enter the REMIX contest :-)

Step 1: Gather Your Materials

As I said I used a 45 gallon plastic barrel, found in a skip, originally container for mortar plasticiser.

I have a large garden so wanted a big container, if you want to make less then use a smaller one

I washed the barrel out just to make sure there were no nasties in it

The Weeds, try to find deep rooted stuff, thistles are excellent, but also dock, dandelions etc - dig the whole thing out including the tap root

You can also use other deep rooted "non weed" plants like Comfrey

Step 2: Fill the Barrel and Add Water

Top up the barrel with weeds and fill with water

Cover and leave for 2 weeks minimum

Step 3: Mmmmmmmmmm Stinky

After 2 weeks you end up with this slightly smelly tea (or soup), the smell isn't too bad - you wouldn't want it in your house but it is fine a few yards away!

Water this soup down 15 to 1 and then water on your plants about once a week

Top the barrel back up when you have finished for the day and it will be back to full strength in a few days

I change out the weeds about every 4-6 months, the old ones are almost completely decomposed and can now go into the compost.

This process releases all the good nutrients into the water so you get the following (amongst others)









I watered my Kumara with this and won the local veg competition with a 1.6kg specimen (See Photo!), it also did wonders for my citrus trees, which were spindly and lacking and now are big and bushy.


A few people have commented about decomposition of seed heads, I generally get my weeds before they have gone to seed, but if you think that the seed heads may still be viable then I advise you to burn the weeds after you remove them from the soup

Edit 2

I watered my paddocks with this mix at a ratio of 10 to 1 I used approx 7 lires (70 of mixed) for an acre, it promotes grass growth and because the soil is richer the weeds don't seem to like it (I believe they prefer poorer conditions) Once you have sprayed your grass keep livestock off of it for 10 days to allow the grass to grow and any nasties to dissipate. Ideally spray before a rainstorm if possible (or during like I did!! :-( )

I will endeavour to answer all questions, and appreciate the comments and advice received so far

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