Liquid Fertiliser

Making Weed Tea and Homemade Liquid Fertiliser

Here is a great way to give back to your garden the nutrients it is already producing and more.  Homemade organic fertiliser will also save you money and cut down on the chemicals which are harmful to the micro-organisms within the soil plus it reduces the plastics which are used in packaging commercial fertilisers.  Reusing your garden waste also increases biodiversity and puts back into your garden the nutrients it would have lost if you threw this material into the bin.

Liquid fertiliser can be made from many different things, some of which are already in your garden such as weeds and vegetable scraps.  Other things you can include are manure or seaweed.  To these you just add water and let it sit for some time. These materials are very high in nitrogen and other nutrients which plants need to grow and be healthy.

There are several methods which you can use, including blending your material, but the simplest method is to soak in a bucket or container with a lid as it can get quite smelly.

Liquid Fertiliser Recipes:

Your recipe may change depending on what you have access to; for example if you live close to the beach you may be able to add seaweed, or manure if you have access to farm or stable.  You can also use eggshells or different herbs grown within your garden.

Equipment and materials needed:

Some of this equipment is not always necessary, especially if you are just wanting to soak and not blend material.

  • One 5 – 10 litre container with a lid
  • water
  • Blender
  • Garden clippings – grass, weeds, garden clippings, herbs
  • Kitchen scraps – raw and cooked vegetables and fruits
  • Manure – poultry, horse, cow, etc – adds nitrogen
  • Eggshells – dried and ground – adds calcium
  • Epsom salts – adds magnesium (1 tablespoon dissolved in 4 litres water)

Types of liquid fertiliser

When using any fertiliser, even organic weed tea, it is best to apply to plants early in the morning to reduce any chance of fungal disease which may occur if the leaves are damp overnight.  Always wash thoroughly any produce for the table, before consuming.

  1. Weed Tea

The simplest and quickest method of making liquid fertiliser is ‘weed tea’.  There are a variety of different ingredients that can be used including herbs such as comfrey, weeds and even manure.

Benefits include: recycling organic waste products, it’s low tech and minimal cost, helps to stimulate microbial activity in the soil, it provides fast nutrients, it’s high in nitrogen which is good for leafy green vegetables as well as addressing some nutrient deficiencies.  What the weeds have sucked from your garden is now returned to the soil.

Weed teas should be used in conjunction with good soil building techniques, which will in the long term, ensure optimal growing conditions for your plants.  Weed tea can also be added to your compost or just used anywhere in your garden.

Items needed:

  • Large container with a lid – plastic rubbish 20 litre bin is ideal or drum. Place as far from the house and downwind where possible as it has a strong smell.
  • Large plastic plant pot to stand inside the bin or a
  • Porous bag, sack or old pillow case
  • String or twine to tie off the bag
  • Weeds, grass cuttings, garden vegetation – with or without seeds it doesn’t matter as they will all rot. Running over your leaves and light garden vegetation with a mower will help to cut it smaller so that it decomposes quicker.
  • Epsom salts – can be used
  • Water – you can save your water from cooking vegies and pasta etc
  • Blender – can be used with small amounts of kitchen scraps.
  • Rubber gardening gloves or tongs
  • Broom handle or stake.

Method:

  • Fill the sack or garden pot, squashing it down as much as possible to fit more in, tie off the bag before putting into the bin. The garden pot can just be put into the bin/drum which is then filled with water.
  • Place the lid firmly on and leave for 5-6 weeks till it has decomposed and has turned into a brown sludgy liquid. The brown is the tannin from the plants.
  • Remove your ‘teabag’ sack or garden pot from your bin with rubber gloves or tongs and set aside to drain.

The sludge from the bag and bag itself can be put into your worm farm or compost bin to further improve your garden health.

  • Stir the liquid with a broom handle or stake
  • Dilute before using: 1 part tea 10 parts water. It will look like weak tea.

  1. Comfrey tea

Comfrey tea is made using the same method as weed tea.

Comfrey is a great addition to any garden.  Not only is it used for medicinal purposes, it is a great border plant which helps suppress both kikuyu and couch.  Comfrey also has very deep roots which enables it to access nutrients from deep within the soil, which are beyond the reach of many plants.  By using its leaves in a weed tea you are effectively making those nutrients available to other plants.

  1. Manure tea

Manure tea is made using the same method as weed tea.  Use a porous bag instead of the plant pot which doesn’t hold the manure as well.

Any single or combination of well matured manure (not fresh), can be used, even pelletised chicken manure and compost works well too. 

Method:

  • Fill the sack to approximately two thirds before tying it closed and placing inside the bucket. The bag can be suspended by a rope or held down with a brick.
  • Stir every couple of days till well steeped for about 2 – 3 weeks. Remove the bag and allow to drain over a bucket.  The contents of the bag can then be added to your compost, worm farm or straight onto your garden beds.
  • Stir the liquid and dilute it at least one part tea to 5 parts water.

For an even faster tea:

  • Use the manure or compost directly in the water (no teabag required). Stir daily.  After about 3 days, strain off the solids and use the tea diluted as above on your garden.

  1. Vegetable scraps fertiliser

You will need: a 20 litre bin with fitting lid, water, vegie scraps, Epsom salt

Method:

  • For every blender-full of pureed scraps, add 1/2 tsp Epsom salt.
  • Put into the large bin or bucket.
  • Repeat this process until all the scraps are pureed.
  • Stir the contents of the bucket well and leave to steep overnight.
  • Dilute this before using: Mix 1 litre of puree to 4 litres of warm water, shake well to mix.
  • Apply to the soil at the base of the plants. 

Making your own weed teas and homemade liquid fertiliser is easy, environmentally friendly, and essentially free. It’s also a great way to transform waste into something valuable, and a terrific way to boost fertility in the garden.