A well-sown wildflower strip is one of the most generous things you can do for wildlife on a smallholding. Two or three metres of native meadow along a field edge will hum with bees by midsummer, feed finches and yellowhammers on its seed heads into autumn, and give harvest mice and shrews somewhere to run that is not a bare ploughland desert. Yet most field margins are quietly wasted: rank rye-grass, a fringe of nettles, a metre of bare soil where the sprayer turned. Turning that margin into flowers costs little more than a packet of seed and a bit of forethought.

Why field margins are worth the trouble

Field edges are the natural meeting point between cropped ground and hedgerow, and they are disproportionately rich in wildlife. A flower-rich strip acts as a corridor, letting insects, small mammals and birds move between hedges, woods and rough corners without crossing open ground. It also buffers the hedge from fertiliser and spray drift, which is good news for the hedge itself.

The practical benefits stack up too. Predatory beetles, hoverflies and lacewings use flower strips as hunting and overwintering habitat, and they spill back into the crop. A firm grass and flower margin on a sloping field slows run-off and traps soil before it reaches the ditch. None of this requires machinery beyond what most people already own.

Choosing the right strip

Look for a margin that gets full sun for most of the day. A south- or west-facing edge alongside a low hedge is ideal; a north-facing strip under mature trees will never be more than shade-tolerant grasses and cow parsley.

• Width: two metres is the practical minimum, four to six metres is better. Wide strips suffer less from spray drift and edge effects.
• Position: leave a metre gap from the base of the hedge to avoid shading and root competition, and keep three metres from cropped ground if sprays are used nearby.
• Length: long, thin strips beat small square plots. A single 100-metre strip will attract more pollinators than the same area in one block.
• Soil: most native meadow species prefer pH 5.5 to 7.5. Very acid or very chalky ground needs a tailored mix.

Preparation and sowing

The single biggest mistake is sowing into fertile ground. Wildflowers are not greedy plants; on rich soil the grasses win and you get a green stripe with the occasional oxeye daisy. If the margin has been mucked or fertilised, take a hay cut or two first, or sow a nurse crop of rye and remove it, before you commit to seed.

Clear the existing vegetation by strimming, then either lightly cultivate or, better on light soils, sow into a short, open sward. Yellow rattle is your ally here: it parasitises grass roots and opens up space for flowers. Sow it in autumn, as it needs a cold spell to germinate.

Use a native seed mix of local provenance, ideally 20 per cent wildflowers to 80 per cent grasses by weight, and sow at 3 to 5 grams per square metre. Mix the seed with sand or fine dry compost so you can see where it lands, broadcast in two passes at right angles, then roll or tread it in. Late August to mid-October is the best window; March to April works on heavy clay, though flowering will be later.

Good species for most of the UK include oxeye daisy, field scabious, common knapweed, bird's-foot trefoil, red clover, selfheal, yarrow and meadow buttercup, with crested dogstail, red fescue, sweet vernal grass and meadow foxtail as the grasses. Never add fertiliser.

The first season

Expect annual weeds and a flush of grass. Cut the strip to about 10 centimetres whenever growth reaches 20 centimetres, and always remove the cuttings. This weakens the thugs and lets light down to young seedlings. Two or three cuts in the first summer is normal. Do not be disheartened if flowers are sparse; most perennials spend the first year rooting.

Managing the strip year on year

Once established, a simple regime keeps it flowering:

• Cut the main block in late August or September to about 10 centimetres and cart off the hay.
• Leave a third of the strip uncut each year, in rotation, so seed heads stand through winter for birds and insects.
• Delay the final cut of any overwintering section until late February or March, once the worst of the weather has passed.
• Top lightly in May only if grass is swamping the flowers.
• Never spray, and avoid cutting between May and July, when the strip is working hardest for pollinators.

What you will see

By the second or third summer the strip should be loud with bumblebees, solitary bees and burnet moths. In autumn, goldfinches and linnets work the knapweed and teasel heads, and the tussocky base gives voles, shrews and harvest mice cover to move safely along the hedge. It is a small piece of ground doing a great deal of work, and it will only improve with age.