Renowned wildflower specialist, Sandro Cafolla shares some insights on how to successfully establish wildflower meadows in Ireland. It’s amazing how our customer’s questions have changed over the years. We used to get asked simple things such as, do wildflowers grow and how and where do you sow them? Back then the primary focus was on creating a big show, a blaze of colour. Nowadays customers are interested in the details of meadow management, longevity and species mixes. The blaze of colour has been overtaken by a genuine interest in wildlife conservation. Interest in wildflower cultivation has grown hugely over the last decade. The new generation of gardeners and landscape professionals is learning about the potential benefits much earlier and this has resulted in a threefold increase in sales.
STARTING WITH A CLEAN SLATE
Although it is perfectly feasible to sow directly into an existing sward, if you first clear the site of all weeds a meadow will have a much better chance to establish. It can be benefi cial in terms of establishment to use a herbicide to clear a site but you should avoid residual products. Make sure you remove the roots of the stronger weeds that herbicides do not kill outright. Even the best herbicides still don’t kill every weed. Weeds which are site specifi c and have a strong foothold will most likely be native to the site, and we recommend working with them. In most cases, regular cutting will control and favour grass and other species. Regular cutting will also reduce soil fertility and generally speaking, the poorer the soil the better the meadow.
CREATING THE OPTIMUM SEEDBED
A level seedbed is not required as long as the seeds come into contact with the soil but ensure that the soil is fi rm below but fi ne and crumbly on top. Before you sow, firm or roll and apply a light raking or harrow to finish the bed and create a freshly moved soil or ‘ferment’, to increase the soils biological activity. Roll and or lightly rake after sowing. Quality seeds in the right conditions should take from four to eight weeks to germinate.
WHEN TO SOW
The ideal sowing times are between mid-March to late May or into July if wet and again in late August to late September. You can sow all year around as long as the weather is mild and some rain is due. 2013 pre-drought sowing germinated by autumn. If you live in the south or near the coast your sowing times will be earlier in spring. Germination will always be slower if the weather is dry or cold.
“Interest in wildflower cultivation has grown hugely over the last decade”
A floriferous display of field margin annuals at the front garden of prouts farm (The location of the upcoming open day).
Bringing life to our motorways. Wildflowers on the sligo by-pass.
SOW WHAT? KNOWING YOUR SEED MIXES
In most mixtures you will find the following: annuals, biennials and perennials. Annuals act as a nurse crop and provide a riot of first year colour. Typical annuals include field poppy, annual mayweed, corncockle, corn marigold. Biennials such foxglove, parsnip, meddick, mullein and wild carrot. flower within 12 months from sowing, and while acting as a nurse they also improve the soil. Both annuals and biennials will not reappear each year unless the conditions encourage them. eyebright, yellow rattle, bartsia and loosewort eyebright, yellow rattle, bartsia and loosewort should persist, as they are annuals adapted to surviving amounts perennial species and grasses.
Every mixture also has a base mixture of perennial species, which will flower for many years. Perennials are divided into two categories; Short lived perennials, which include ox eye daisy, red clover and sorrel have short life cycles and require regular gap creation to ensure they persist. Long lived perennials such as bluebell, cowslip, field scabious, meadowsweet, hypericum and many more are long lived and will persist for years provided that the meadow is managed appropriately. Wildflower seeds vary in weights and sizes, so always stir the seed before and during sowing to ensure that the seeds of all sizes are spread over every metre.
A good meadow starts with good quality seeds in the right mix for a particular context. Avoid generic store bought mixes. They are simply not as effective and can cost more in the long run.
A MEASURED APPROACH
In most cases a gram and a half of 100% wildflower seed (that’s a level teaspoon) is used to sow one square metre If you’re sowing a mix that contains grass seed then you need to double the quantity to three grams per square metre and 50/50 grass wildflower ratio (this equates to 13.2 kilos per acre or 30 kilos per ha).
BROADCASTING IS BEST
There is a range of different methods for sowing seed, from simple hand casting to using complex commercial machinery. In my opinion seeds are best sown by hand or with an aero type seed fiddle. Many of the commercial sowers are unsuitable as the seed separates and large seed goes in one direction and small in another. Seed also settles in large spreaders with small heavy seed coming out first, so if you must use a seeder, use a small amount at any one time. To sow seeds, use the broadcast method. Stand with your back to the wind if at all possible, start at one end of the bed, one metre out from the edge and be careful to only sow one metre wide. Scatter the seed and try to avoid chucking it out in one place. Sow the seed as soon as ground works are complete, as the soil will be at its best in microbial activity and the gasses released will really get your seeds o¤ to a good start. Seed should be covered to approximately 3mm on dry soils to avoid it drying out.
Wildflower seed germinates in response to sunlight so the deeper you bury it the less chance of successful germination. As long as the soil remains moist, wildflower seed does not have to be buried, just raked into the soil, barely covered and rolled to ensure that the seed contacts the soil. Press the seed into the surface on sticky wet soil. All wildflower seed is barbed when viewed under an electron microscope, it uses the bards to work its way to the best level in the soil.
TO CUT OR NOT TO CUT
If you grow our mixtures (without grass seed) an established meadow will need only one or two cuts per year. When you first sow your meadow, do nothing for the first summer; enjoy the cornfield annuals as they provide a riot of summer long colour. Cut the annuals in September and rake afterward. If sown without grass, annuals won’t really have to be raked in the first year and the seed provides bird food. In the second year, do even less, as biennials reach for the sky in a blaze. Like annuals, biennials are short lived and may not return. There are many ways to cut a meadow. Whichever method you choose, always remove the cuttings, rake them up and then rake over the bare soil to scratch the soil to help new seedlings germinate. We recommend this extra raking to allow in ultraviolet sunlight, which helps to sterilise the soil, kill moulds, make space for new seedlings and to provide fewer places for slugs to hide. Decaying vegetation causes mould, which affects new seedlings. The fresh air can then blow over the germinating seedlings. The additional raking or scratching helps recently shed seed from your meadow to contact the soil. Wild flowers shed new seeds every year. It is this process of cutting and raking which renews a meadow. This work replaces hay cutting and animals grazing the, after growth, which was how meadows got started in the first place.
“Nothing compares with the stunning clouds of butterflies, flocks of birds and insects galore, and a host of fauna that you will find in a well-grown meadow”
Meadows can be topped with a lawnmower instead of cut, and if it is done often there is no volume to the foliage. But it needs to be done regularly to avoid the meadow getting out of hand and becoming impossible to cut with the lawnmower.
ESTABLISHMENT AND MAINTENANCE IN THE EARLY YEARS
When you first sow a meadow, seedlings will keep on germinating each spring and autumn until about the second or third year. This is when maintenance is required. After the meadow is established your job is to manage it with one cut per year. But if your soil is fertile you might have to wait up to seven years for fertility to drop, and must maintain it fully as done in years two to three. Correct timing when cutting the meadow is crucial to the survival of seedlings. A meadow is won or lost at this stage. If your original cultivation methods did not produce a clean weed-free seedbed, this is your last chance to get rid of stones and weeds that you have missed. Any meadow can be cut every 30-60 days to keep tidy as a lawn. On very barren sites you may not have to cut at all, instead roll with a Cambridge roller.
Meadows should have very little chemical inputs, bar occasional low volume spot spraying to eradicate ragwort, dock and thistle. Both are green in winter, but non-fertilised lawns turn yellow in dry summers, whilst wildflowers flower better in droughts, and often hidden species appear in the severest of droughts. Use of chemicals should be avoided, but if the meadow is going to be destroyed by an infestation then you may need to make a pragmatic choice.
Basic in-house research on meadows in public parks over 10 years shows that growing wildflowers is much cheaper with less trouble, and far more enjoyable than large areas of lawn. A lawn is still good for wildlife, but nothing compares with the stunning clouds of butterflies, flocks of birds and insects galore, and a host of fauna that you will find in a well- grown meadow. Go wild this summer!
SANDRO CAFOLLA is considered Ireland’s foremost expert on the production of Irish wildflower seed and the creation of wildflower meadows. He has been at the forefront of the sector for over 25 years, has supplied species to over 3200 projects, across 32 countries, covering everything from domestic gardens to major infrastructure works. He can be contacted at firstname.lastname@example.org or via his website www.wildflowers.ie