Clues as to the best method for enhancing grassland with wildflowers can be found in what you've already got. If the sward is herb-rich – it might contain ribwort plantain or cat's ear, yarrow or selfheal – then altering the cutting regime will give these plants a chance to flower and set seed.

However, if coarse grasses dominate and you need to make some space for wildflowers, then yellow rattle Rhinanthus minor is the best plant for the job! It is semi-parasitic, weakening vigorous grasses and opening up the sward to give more delicate broad-leaved species an opportunity to germinate and compete.

You don't need to collect a huge amount – remember you'll only want to sow the seed at a rate of 2–3g per square metre. For best results, seeds should be sown in the autumn, so, as you'll only be storing the seed for a short time, keep the dried seed in a paper bag in a cool, dry place.

Dorset Wildlife Trust harvests many kilos of yellow rattle every year in partnership with Hogchester as part of our Meadow Makers project. You can buy small quantities of seed from the Hogchester eBay Store or, if you're in West Dorset and need larger amounts, contact Nick Gray or Rowan Watkins with details of your meadow restoration project. All proceeds go towards making more meadows!

Frosty winter weather, with some dampness, makes for ideal 'vernalisation' conditions, breaking seed dormancy. Therefore, if possible, get the seed down in September to maximise natural vernalisation.

Wildflower seed needs to make contact with bare earth to germinate. To broadcast it, first cut the grass very short, then scratch the ground with a rake to reveal about 50% bare earth (don't be shy!) and strew the seed evenly. The focus of this article is rattle and its parasitic properties, which create the right conditions for other flowers in the future, but you might like to throw down a few other seeds too while you're at it. Species will depend on how vigorous your grass is, as above, but oxeye daisies are always an encouraging species to pop up on a newly sown site, as is black knapweed; both compete well.

Rolling the area will ensure the seed makes contact with the soil, or alternatively, you could mimic livestock 'aftermath grazing' (after the hay cut) and tread the seed in with your own soles!

Very important: the following season, you must ensure that any winter grass growth is cut back very short by the end of March to give yellow rattle the best chance of germination. On a farm, this would be done with early sheep grazing, but your site may need mowing or scything if ground conditions allow. Then sit back and let the new plants flower and set seed – in other words, leave the area uncut until July. Scythe the long grass thereafter (or strim, in fairness) and remove the cuttings, mimicking the agricultural hay cut.

If the yellow rattle has worked its magic in a year or two (suppressed grass growth and produced a 'finer' sward), you can repeat the process with small amounts of hand-collected seed from a wide variety of species to continually enhance the flora in your grassland – the more local, the better! Choose an appropriate 'donor site' to match the characteristics of your receptor, e.g. soil pH. Autumn is by far the best time to strew wildflower seed – this is, of course, when it naturally falls and either germinates in warm autumns to give itself a head start the following year or lies comfortably dormant until the following spring. Good luck and happy rattling!