No-dig is the single change that saves the most work on a vegetable plot, and autumn is the one window in the year where making a bed costs you nothing but a wheelbarrow and an afternoon.

The idea is not complicated. Instead of turning the soil over, you put organic matter on top of it and let the worms take it down. The soil structure that took years to build stays intact, the weed seed buried in it stays buried and dark, and you sow into a loose, crumbly surface every spring without ever picking up a spade.

Do it in September or October and you get seven months of worm activity before you need the bed. By March it has knitted itself together and you can sow straight into it. Do the same job in March and you are sowing into a heap of loose compost that has not settled - it works, but it is second best.

What is a no-dig bed, actually?

It is a layer of compost placed on top of undisturbed soil, and that is the whole of it.

Not a raised bed - though it can be. Not a special mix - ordinary garden compost or well-rotted manure will do. The bed is defined by what you do not do to it: you do not dig it, you do not fork it, you do not rotavate it. You add to the top, and everything else happens below the surface without you (RHS no-dig guide).

Why it works comes down to three things. Soil is a structure, not a substance - digging destroys the channels and crumbs that let water in and roots through. Weed seed only germinates in the top few centimetres, so if you never bring buried seed up, you never get the flush of weeds that follows a dig. And the fungal networks that feed plant roots are threads: cut them every spring and they never get established.

When is the best time to make a no-dig bed?

September to November, and September is better than November.

The soil is still warm and the worms are at their most active. Put 10cm of compost down in September and by March most of it has been dragged down into the top layer of soil and turned into the crumb structure you will sow into. The same bed made in January sits there cold and inert until spring.

You can make a no-dig bed at any time of year, including the day before you plant into it. Autumn simply means the bed makes itself while you are indoors.

How do I make a no-dig bed on grass or weeds?

Cardboard, then compost. You do not need to remove the grass and you do not need to dig anything out.

  1. Cut it down. Mow or strim as low as you can. The material stays where it falls - it is the first layer of your bed.

  2. Water the ground. Dry soil under cardboard stays dry for months. Soak it first, especially after a dry autumn.

  3. Lay the cardboard. Plain brown corrugated board. Take off the tape and the plastic labels. Overlap every sheet by at least 15cm - the gaps are where the grass comes through, and it will find them.

  4. Wet the cardboard. Properly. Dry cardboard blows away and does not rot.

  5. 10 to 15cm of compost on top. This is the bed. Rake it level.

  6. Leave it. The cardboard is gone by spring, the grass under it is dead and has become food for the worms, and the compost has settled into a sowing surface.

That is a bed made on a lawn, in an afternoon, with no digging and no turf lifting. It will grow a crop next season.

Do I need cardboard for a no-dig bed?

Only if there is something living underneath that needs killing.

Cardboard does exactly one job: it excludes light for long enough to kill grass and annual weeds without you removing them. On bare soil, or on an old vegetable bed that is already clear, it does nothing useful and you can skip it entirely - just put the compost down.

Where it earns its place: lawn, a weedy allotment plot, a path you want to convert. Where it does not: a bed you cleared last month, or a bed you are topping up for the second year running.

One caution. Cardboard suppresses annuals reliably. It does not kill couch grass, bindweed, ground elder or horsetail - those have deep root reserves and will simply push through or grow sideways and come out at the edge.

How much compost do I need for a no-dig bed?

Ten centimetres for a new bed, two to five centimetres a year after that.

The arithmetic is straightforward. A bed 1.2m wide by 3m long is 3.6 square metres. At 10cm deep that is 0.36 cubic metres - roughly nine or ten builders' barrow loads, or about a third of a bulk bag.

Two things bring that cost down. First, it is a one-off: after year one you are topping up 2 to 5cm, which is a quarter of the compost. Second, the layer underneath does not have to be finished compost. Half-rotted material, leaf mould, spent potting compost, even a layer of grass clippings and autumn leaves - put the rough stuff at the bottom and the good stuff on top, because only the top few centimetres need to be fine enough to sow into.

The one genuine rule: whatever you use must be rotted enough not to rob nitrogen. Fresh woodchip and fresh manure will both take nitrogen out of the soil as they break down. Use them as a path or a bottom layer, not as the surface you sow into.

What about perennial weeds - bindweed, couch grass, ground elder?

Cardboard and compost will not beat them in one season. Be honest with yourself about this or you will be disappointed in May.

These weeds store energy in their roots and re-shoot from any fragment left behind. Digging makes it worse - every chopped piece of bindweed root becomes a new plant, which is exactly why rotavating a bindweed-infested plot is the single worst thing you can do to it (RHS weed guide).

What actually works is exhaustion. Cover the area with cardboard and a thick mulch, and then every single time a shoot appears, snap it off. Every shoot the plant sends up costs it root reserve, and every one you remove before it makes a leaf is energy it never gets back. Do that consistently for a season and the plant runs out. Do it half-heartedly and it wins.

For the worst infestations, cover the ground with a light-proof membrane for a full year, grow nothing there, and start the bed the following autumn. A year of patience beats five years of fighting.

Can I convert an existing dug bed to no-dig?

Yes, and this is the easiest version of the whole job.

Clear the crop debris. Do not dig. Put 5 to 10cm of compost straight onto the surface - no cardboard needed, because there is nothing living under there to kill. Rake it level and walk away.

Next spring you sow into the compost layer. From then on you top it up once a year and never dig it again. Most people notice the difference in the second year: the bed drains better after rain, dries out more slowly in a heatwave, and there are visibly fewer weeds because you have stopped bringing buried seed to the surface every spring.

What can I plant into a new no-dig bed?

Anything, with one honest exception in the first year.

A bed made this autumn is ready in spring for everything. Potatoes grow superbly in no-dig - you lay them on the soil surface and mulch over the top - and so do courgettes, squash, beans, brassicas, salads and alliums.

The exception is long, straight roots. Carrots and parsnips sown into a fresh 10cm compost layer over unimproved soil sometimes fork where the root hits the boundary between the two. It is not a disaster and plenty of people ignore it. If you want perfect carrots in year one, sow them somewhere else and put them in the no-dig bed from year two, once the compost and the soil below have properly merged.

Does no-dig actually save work?

Yes, and the saving compounds.

Year one is real work - you are moving compost, and there is no way round that. But you never dig again, the weeding drops away year on year as the seed bank in the top layer is exhausted, and the beds hold water so much better that watering in a dry summer is a fraction of what it was.

The point of no-dig is not that it is a clever technique. It is that the soil does the work that you used to do, and it does it while you are not there.

Start it this autumn and the bed is ready in March without you touching it again.