A "weed" is basically a plant that's really good at growing. Some of them are very beautiful, and many of the plants considered weeds in one area are not considered to be so in a place where the climate is different and the plant is not as good at growing, thus can be "controlled". My favourite weed is clover, every kind of clover ever, and I tend to leave it, unless it's growing in one of my pots.
The problem with weeds is not so much that they're good at growing, it's why they're so good at growing. Weeds are nutrient sucker-uppers, which robs the other plants around them of nutrition. Clover (best ground cover ever!) doesn't do so much of this, and actually adds nitrogen to the soil, which makes the other plants sharing the soil with it (such as grass) greener, but can stop them from flowering, which can be good if you don't want a plant to go to seed. Enough about clover, I digress.
As I have said, most weeds are nutrient sucker-uppers, which is why you don't want them in your garden
You can, however, use the nutrients locked up in weeds to feed your lawn and garden. You can't put weeds directly in the compost, because the compost heap is a great place to keep seeds dormant until you spread them all over your garden and they sprout up big and healthy, nor should you use weed killer on weeds you intend to feed plants with, but what you can do is very simple.
To feed your lawn, you don't even have to dig the weeds out. Find a weed, like this one:
For gardens, you can make some lovely, smelly compost soup! Compost soup is also called weed soup, weed tea or compost tea. You will need a black plastic bag and some patience.
Dig out as many weeds as you can roots and all and place them in the black plastic bag. Cover them with water, tie the bag closed and put it in the sun to "cook". Before I tied mine shut, I also added a tiny splash of this:
The bag should be left in the sun for at least a week.
(exciting picture of a bag, there)
To prepare the soup you will need a container large enough to hold the liquid, a strainer or some folded paper towel and gloves if you don't want wet, mucky hands.
After a week, the soup in my plastic bag looked like this:
and smelled like bunyip farts, which is good as it means the weeds have broken down. I wanted to add a little extra boost to my soup, so I added a little black tea to the container before filtering the soup.
I don't have a strainer for my garden right now, it's on my list, so I used two sheets of paper towel as a filter.
It was working well until it got too heavy and tried to fall in. I squeezed it out into the container and got more paper towel, this time a stabbed some little holes in it. I carefully tipped the bag and poured into the filter I had made.
When there was no more loose liquid in the bag, I took handfuls of the mushy weeds and squeezed as much as I could out of them (that's where gloves are handy).
And there you have it. Compost soup. All you need is about a quarter of a cup of the liquid in 9 litres of water (standard watering can) about once per month. Super! :-)
I put all the paper towel I used in the process and all the dirt that had come from the roots of the weeds in my compost, along with the now safe cooked weeds. :-)
Happy gardening! Love to you all!