September is a prime time for sowing wildflowers, when grass growth is slowing, meaning the flowers have a chance to come through. Whether you're planning agricultural margins or environmental schemes, or using wildflowers to enhance roadside verges and central reservations, here's a quick reminder of how best to do this.
How much seed do I need?
2.5 grams per square metre or 10 kg per acre (25 kg per ha) maximum. Putting on more than this will mean the stronger species (grasses) will start to dominate. Mixes are created with specific sites in mind and choosing the right mix is really important. If the area you wish to sow is chalk or limestone, acid or clay, damp or shady, then choose a mix created for those particular circumstances, otherwise a general purpose one is best.
Getting the soil ready.
It is important to control any weeds in the area to be sown before the seeds are broadcast. Problem weeds are docks, thistles and nettles as these cannot be removed easily once the meadow area is sown. Weed control can be done one of two ways:
1. Herbicide spray
2. Stale seedbed technique - prepare the seedbed as usual then wait a fewweeks for weeds to germinate, then cultivate again to destroy and bury theweeds. Then sow your seed.
Once weeds have been dealt with, prepare a fine, well-worked seedbed and give it a roll. Then broadcast the seeds by hand or using a spinner. Once this is done, harrow or rake the area, then roll it again to ensure the seeds are in good contact with the soil.
Can I introduce wild flowers into existing grass?
If an existing meadow starts to look thin, then it is possible to overseed with just wild flower seeds, although to do this successfully the area must be harrowed before hand to ensure the seeds reach the soil and the existing plants are knocked back.
How will I manage a wildflower meadow?
If left alone, a wildflower meadow will quickly return to scrub with the more competitive species taking over. Any wild flower meadow should be mown during its first few seasons to control annual weeds. In the second year, let it flower before mowing. This will vary year to year, but is normally around August. After mowing, removing the cuttings. This helps decrease the fertility of the soil so favouring delicate wild flowers. If you have very poor growth on thin soil, then cuttings can be left.
Preventing grasses from smothering the flowers.
When choosing your mix, opt for fine, non-aggressive grasses. Exclude the more competitive grasses such as ryegrasses, cocksfoot and agricultural forms ofTimothy. Heavy, clay-rich or fertile soils will encourage grass growth, so meadows are most successful on lighter, drier, free-draining soils.
Coping with weeds after sowing.
Any perennial weeds should be cut out or spot treated. Annual weed varieties will disappear after the first season of cutting.
How long do wild flowers last?
Wild flower meadows, once successfully established, should be permanent, and will improve with age, but only if they are managed as advised in the first few seasons, as mentioned above.
Can I grow wildflowers on fertile soils?
Wild flowers prefer infertile soils, so do not thrive in areas of high fertility. Some enthusiasts remove fertile topsoil exposing less fertile subsoil. If established correctly on the right type of soil, the balance of species should be harmonious. Any imbalance normally means the soil is too heavy, too wet or too fertile, so favouring grasses.
Can wildflowers be sown into a lawned area?
This can be done by broadcasting seed in early spring and then stop mowing altogether. It’s also advise to scarify or harrow to remove some of the grass cover, before sowing the seed. We supply a wild flower only mixture which can be used for this purpose. However, the strength of the grasses in the lawn mix will determine the success of the wild flowers, as will the site's soil conditions and fertility.
Date Posted: 31st August 2016