The veg garden looks pretty bare once the summer crops have been cleared away. So you're faced with a decision: to cover or not to cover?

Traditionally, farmers would clear a field and plough. Gardeners adopted this technique for kitchen gardens, allotments and veg patches by rough digging. This helps clean up the soil by exposing pests to the attention of watchful birds and, when muck is added, reputedly enriches the ground as the muck gradually breaks down and is absorbed by the soil.

Undoubtedly this is an excellent form of pest control and rough muck or compost does weather over winter. Even so, I have found it takes more than one winter for farmyard manure to be completely incorporated into the soil. It must turn into crumbly compost before it will add the desired nutrients.

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And research has repeatedly shown that leaching removes much of the soluble nitrates in the muck over winter. Leaching slightly acidifies the soil, thereby altering the soil’s microbe population. And, perhaps more damagingly, acidification leads to fewer worms, those little fellas whose mass of tiny tunnels helps keep the ground light and airy. The soil is also compacted by frequent pounding of winter rains.

The most effective way to keep soil healthy is to lock up surplus nutrients in a growing crop, a green manure. Plant cover also reduces the impact of winter downpours. Although there’s a wide selection of attractive green manures, such as phacelia, only the likes of grazing rye survive a Scottish winter.

This approach is isn’t always ideal, though. The seed is fairly expensive and in my experience must be sown no later than mid-September for good germination – just when the ground is still occupied.

Needless to say many weeds are less choosy than grazing rye and would readily provide a green sward. I’ll turn down that offer, given how much weeding I have to do without letting more weeds set seed.

Although you can’t add goodness to a piece of bare ground by spreading a permeable plastic membrane on it over the winter, you will retain its structure and most nutrients. When you remove a membrane in spring, you’ll reveal good, crumbly, loosely packed soil. As a bonus, you’ll find couch or ground elder roots lying enticingly on the surface, ready for grasping.

Alternatively, you can retain structure by laying an organic mulch. I’m lucky to have an excellent supply of decomposing poultry bedding. It’s fairly low in nutrient levels but I find a thick layer works beautifully, especially if I spread the last of the grass clippings on top to help the straw break down.

When I plant the next crop in spring, I will rake away any surface straw and compost it. I get a few weeds round the edge of a bed, where the mulch has been thinner, but otherwise the ground is virtually ready for planting. This dry, brown material is very useful in spring, when most compostables are raw kitchen scraps and green, sappy stuff.

You could use other low-nutrient organic materials instead as a mulch, such as municipal green waste, bearing in mind that it might contain garden pesticide residues. Woodchip and forest bark are possible, but you’d have to carefully remove it all in spring to prevent nitrogen robbery. Rather than feeding your plants, some nitrogen would be used to break down the woody matter. Sawdust should always be avoided as you could never lift it away in spring.

Inevitably, there’s a downside to mulching as well. Just think of all those little molluscs and cutworm eggs sheltering snugly, all set for a busy spring.

Like everything else in gardening, it’s all down to balance. Conserve structure and nutrients most of the time, but expose the pests to helpful foragers once every three or four years.