Jamie’s Little Allotment: Gardening tips for harvesting and preventing bare soil

In his weekly Jamie’s Little Allotment column, gardener Jamie Marsh discusses harvesting and what to do to prevent bare soil...

So September brings autumn, summer has passed and the nights are pulling in.

It’s not all over in the allotment though.

Harvesting is at full speed, beetroot, carrots, French and runner beans, courgettes by the bucket full, and even the odd corn on the cob is ready.

And thankfully the tomatoes are starting to ripen.

But of course the more you harvest the more bare soil is revealed, and bare soil is not what we want at the plot.

It’s not great to let your soil lie bare over the winter months. The wind, rain and cold will damage the precious top layer; it will lose nutrients and structure, and start to erode.

So as your beds start to become empty if you don’t provide a blanket, nature will do the job with weeds.

Instead of leaving your beds bare, you can cover the soil with lots of things such as mulches, cardboard or black plastic, but by far the best option is plant life.

There’s lots of evidence to prove a soil that is actively growing plants in it, keeps its food web below the surface healthy and resilient.

That is why the soil will choose weeds if you don’t cover it with something else.

The alternative, so that you don’t have to break your back weeding, is to plant green manure, quick-growing crops that will cover the ground, outcompete most weeds, and help build soil and protect it from erosion.

Green manure will also lock in nutrients that are easily lost in the deluge of winter rains. In spring, the green manure is either dug in or hoed off to rot back, releasing the nutrients into the soil for the next crop.

There’s a window of opportunity from now until the end of September, while it’s still nice and warm to get some of the easiest ones growing.

At the point you decide you’ve finished growing in a certain bed, hoe the ground flat and resow with green manure.

There are two main types for the end of summer. The first are quick-growing plants that are not hardy and will be killed off by the first hard frost.

The dead stems and leaf matter are left in place to further protect the soil; worms will incorporate them into the soil by the end of spring.

Common buckwheat and white mustard are good examples. Scatter the seeds, rake them in, and let nature do the rest.

There is also perennial clover which is great green manure.

These can be grown either over winter or left for a couple of years as a long-term green manure.

Clovers are known for their nitrogen-fixing root nodules that feed the soil and are good at suppressing weeds.

If you decide to use a perennial clover, make sure you chop the foliage down and leave it to wilt before it sets seed, or you will have clover popping up for years to come.

After telling you all about the green manures - I don’t actually use them.

I try and keep things growing all year round, but if I don’t, I will mulch my beds. Hopefully, my empty beds will be weed-free so I add a two or three-inch layer of homemade compost or well-rotted manure, by the time spring comes around, the worms will have done their job and it will be ready to plant in.

If you are struggling with weeds in your beds before you mulch you can add a layer of cardboard, which will block out the light and kill the majority of weeds, and will have broken down by the spring. Then you can plant in, and sow your seeds into a weed-free fertile soil.

Email me at jamieslittleallotment@gmail.com if you have any questions