I made my first garden bed.
It took me about a day of work to gather enough material for a small 2-to-3 meter-long structure, following the method known as lasagna gardening. You don't dig anything, but you make a raised bed layered with green and brown waste. You start with 5 cm of green waste (I used freshly mown grass and green leaves), then 5 to 8 cm of brown waste (dead leaves). You repeat once and top everything with a layer of green waste. I also added a last layer of ramial chipped wood to act as a mulch.
Making ramial chipped wood without a wood crusher took me half a day spread over two days. The rest of the time was spent gathering fallen leaves, mown grass, making the actual thing, and carrying water to humidify the different layers.
I'm incredibly satisfied with the end-result, but I won't be able to use the raised bed until Spring. I'll try another gardening method in the meantime to grow some garlic, and perhaps gather fresher material to make another lasagna.
A raised bed layered with ramial chipped wood is a way to imitate forest vegetation, increasing the quality of the soil while improving water retention. It's a great alternative to more traditional methods, but I have to see the results of this little experiment.