Fertiliser isn't cheap - neither is organic fertiliser. I'm also a cheap skate and seeing as during the growing season you need heaps of fertiliser for fabulous veg, here's a guide to making your own.
For this instructable you only need:
Container - preferably with a lid
A thwacking stick.
Step 1: Collecting Nettles
Good stout gloves are a must, however you may also need a long sleeved jumper or thick long sleeved t-shirt to get a proper harvest.
Harvesting is simple - just pull up plant. Leave the roots if you can, but you ought to be able to snap off the stems without too much effort. You'll need enought to fill your container - don't be afraid to compact it down either.
Step 2: The Thwacking stick
All you need to do is damage the nettles. A lot. Take out those years of stinging anguish with your thwacking stick. The more damage you make, the more surface area there is for bacteria to break down the nettles quicker. I've done this process without thwacking, but generally it's much quicker to break down the nettles first. You could even stick them in the blender...
What is a Thwacking stick you ask?
Its anything which makes a satisfying twacking sound! You can infact use any device for mashing and smacking the nettles - a lawn mower can be used to finely chop the leaves, or just like I have, a bit of 2x1.
The twacking can be done on the lawn, on the pavement or in the container (as long as it's strong enough)
You can either fill the container with water and pulverise them there, or twack and add later.