A neighbor on the allotment site stopped by my plot, which is covered with a thick layer of mulch, mostly hay. When I say thick, I mean it, the layer is around 15-20 cm, which I applied on the soil last autumn. He asked about the benefits, challenges. My organic answer was that I have reduced half of the problem- weeds. Slugs are yet to be managed.
Last year, I inherited a beautiful plot in Cardiff, 5 perches, on a sunny position. The garden was covered with plastic sheets, which I instantly disliked. Why plastic, when there is a much better option, that brings more benefits than polymers? Last year I mostly spent clearing the plot, as there was quite a lot of rubbish too. Lockdowns certainly didn`t help, so I piled everything on a side and waited for the skip to come. Having a busy life means that I couldn`t be on the plot daily. Weeds recognized my absence and simply took the plot over. Oh dear, they were thriving in a humid climate, good soil, and Sun. The stems of some weeds were thick as my fingers, and obviously, they were higher than the veggies. They took the plot over and I was desperate- an overgrown plot with a huge pile of rubbish. I thought, do I need another issue in my life?

Then I stepped back, read my old notes about the mulching, and made a decision to start again. Despite everyone told me not to go that route, because of the slugs. I bought 20 bales of hay, applied manure on the soil, and covered 90% of the plot (except the paths, but those will be covered too). I thought to myself, what can go wrong, if I decide to stop mulching, I`ll simply stop applying more materials, the existing mulch will decompose and problem solved.

Pass me your weeds, please.

Back to the neighbor. I explained to him the benefits of deep mulching, you get far fewer weeds, no need to water, the mulch boosts wildlife and it decomposes- enriches the soil. Then I pulled a weed out, the white section between the root and the green part was long as the thickness of the mulch. The weed was pulled out easily, with the root. I simply shook the soil off and put the plant on top of the mulch. He asked if the plant can root again, and the answer is no because the root needs soil and humidity to grow. If left on top of the mulch, it will dry out and became the part of mulch soon. I told him to pass me his weeds if he doesn`t have the compost bin.
Now, the natural conclusion here is to mulch with more diverse materials, because they contain more and different nutrients. Hay is better than straw, and weeds/leaves/sawdust with hay is better than hay alone. Let`s get greedy here, the more the better. If you have an access to comfrey, cut the leaves and scatter them around the ploT, all that will become rich soil one day.
What about thick stems like corns, sunflowers? Absolutely yes, cut them into smaller pieces, so they are easy to handle and scatter them around. They are not too thick, they will simply last longer.
Some people asked if they can scatter kitchen waste- absolutely yes. If you don`t like how it looks, you can cover them with more hay. You might get some mice or rats, this is something I can`t comment on as I`ve never done it. Kitchen waste goes to a composting bin in my garden.

This year I unusually cold, so I still haven`t planted many crops on my plot, and I can`t answer many questions about the correlation between mulch and slugs. If I lift some mulch, yes, I can find some slugs, but how much damage they will do, I don`t know. My salads are still alive and pretty much intact. I find beer traps, mechanical collecting, and Nemaslug the best slug options, even though I doubt that Nematodes will work in mulch, this is something to be tried.