The allotment is slowly coming along. It is no longer a place full of weeds and is beginning to become the space that I dream of. It still looks like an allotment; there are various recycled accoutrements, windowpanes, old net curtains, piles of cardboard and newspaper. To some visitors it's a mess; to others this is its true vernacular, lovingly built out of leftovers.

Last year, I experimented with weed-clearing methods. I divided the allotment in half. On one side I dug meticulously, removing couch grass and bindweed root, putting them in plastic bags to rot – I don't want to lose all that goodness the weeds have robbed. Eventually I'll add them to the compost.

On the other half I used a no-dig American method called lasagne gardening, where weeds are buried under layers of organic material.

Cut down large weeds, spread out a thick cardboard mat (several layers at least, soak it with water to help it rot, and start layering. Semi-rotted leaves, grass clippings, rotted manure or garden compost are the meat layers, more cardboard for the pasta. Do this several times and finish with soaked cardboard.

Now, the American references say you can plant straight into your lasagne. In reality, there is a lot of nitrogen lock-up. The carbon-rich cardboard steals (temporarily) the nitrogen to start the decomposition process (which is why you need lots of nitrogen-rich grass clippings). This is fine as long as you use larger plants, and I can see it would work well for perennials.

As the cardboard is wet, it's pretty easy to dig into, but as the layers are semi-rotted, it is essential that the plant has enough soil around the roots to hold its own. It will eventually send new roots to explore. My attempts at using smaller plants were hampered because I think it was too much of a shock, so my small pumpkins suffered, as did other young plug plants.

I rescued the pumpkins by feeding them with liquid comfrey. The runner beans and tomatoes loved the rich, semi-rotting soil and grew fine.

Recently I went to have a little dig: I was amazed. I'd say 95% of the weeds have gone (roughly the same as the dug area, but with no broken back) and the soil is rich with life (not so for the dug-over half). Fat, red wiggling worms, beautiful, dark, crumbling soil – you can tell that all the good has been trapped in. It's a joy to look at; it feels substantial in your hands. I love this soil.

Watch Alys' lasagne experiment.

Alys on the big spring tidy

Those winter seed heads that were so spectacular in frozen December are a bit bashed now, and the slime and rot of the thaw lingers. Now's a time for a bit of tidying. Not a deep clean – insects still need their homes – just a clear-up here and there. Cut back seed heads or dead overwintering foliage. Assess frost damage (there should be signs of life). Gently scrape stems of damaged plants with your thumb – if there's a hint of green, it's coming back. Be patient: it may take some time. To a degree it's down to root size. An established plant with a good root system can often weather the rough. Have a bit of a dig, mulch healthy roots with compost and cross your fingers.

Now is also a time to split overgrown perennials – sedums, geraniums, day lilies, centaurea or lychnis: the ones that like to beef up. Two forks back to back will prise apart clumps, or slice them with a spade. Discard woody middles and half-chopped tubers or roots. A good-size clump is 15-20cm across. Replant with compost. It's amazing what a bit of a tidy-up does for the spirits and a tired-looking garden. Get ready, because March, and the growing season, is almost here.