Wildflower seeding, problems & solutions
Added at 12:06 on 13 March 2023
I have been offering my gardening service for nearly 30 years to both private and commercial clients. Although an eco-friendly approach has always been around during this time, it is now starting to become increasingly popular with sowing mixes of wildflower seeds to attract pollinators, particularly with commercial clients, a common request.
Numerous books, websites, media articles and wildflower seed supplier literature is available to provide informative step by step guides on how to prepare the ground and sow the seed mixes.
I have found the guides supplied by suppliers such as Rigby Taylor, Boston Seeds and Scotia Seeds provide sufficient concise recommendations. For those wanting a more in-depth discussion ‘Sowing Beauty’ by James Hitchmough is detailed but heavy reading.
My experience from carrying out two commercial showings for the same client for 160 sqm area has provided mixed results. The first sowing (spring 2021) was done using standard horticultural grass seed sowing procedure. After strimming down the existing vegetation I sprayed the area with a glyphosate based weed killer (I know bad, I am gradually changing my ways) to reduce competition with the wildflower seeds. The ground was then rotovated (not environmentally friendly either) raked level and sown with an annual wildflower seed mix to provide colour and pollinator resource in the first year. Wildflower seed mix comes in much smaller quantities than grass seed mixes.Less is required to cover a given area so it is best mixed with a carrier such as sand with half the mix spread in one direction and the other half in the opposite direction. The first years attempt was not too bad although a dominant weed species called fat hen, Chenopodium album, growing to 1.2m dwarfed some of the wildflowers in the mix.
I was given authorisation to do it again the following year (2022) and in this attempt I wanted to deliver really good results. I studied numerous books, video tutorials and supplier literature, even consulting the experience of Dundee City Council’s wildflower specialist who has carried out numerous sowings throughout the city over a number of years. Perennial (long lived species) sowings are much more difficult to achieve success. They normally don’t look good till the second year, requiring the first year to make vegetative growth. However after the second year they tend to decline as the existing weed seeds start to make a strong, and unless lots of human intervention, a successful bid to retake their niche. Sowing of annuals are much more likely to give good results.
Again using similar environmentally unfriendly practices I strimmed down existing vegetation, used glyphosate and rotovated the ground causing stress and injury to soil biodiversity in the process. Although where I garden in north east Scotland is not short of sufficient rainfall it never seems to rain after I sow seed so I had an outside water tap installed and had hoses at the ready to aid seed germination. The only practice I did not do was, as Nigel Dunnett suggests in his book ‘ Naturalistic Planting Design’ was cover the area with a 2 inch layer of sterile sand (or other medium such as compost) on which to sow the wildflower seed mix and hinder the emergence of of existing weed seeds. This is supposed to act as a lag inducer allowing the wildflower seed mix to get a head start on the ‘weeds’ in the existing soil seed bank. The reason for this was time and cost required to implement and my question ‘Does this procedure have to be done every year to hinder the germination and emergence of the existing enduring native seed bank?’
As the year progressed, the soil getting warmer and sufficient natural irrigation from rainfall being available, with every site maintenance visit I monitored progress of my tall species wildflower meadow, taking photos every visit. In time I realised having followed all procedures in text book practice that I had achieved complete failure. Poor, sparse and uneven germination. In a cloud of humiliating gloom I now looked forward to being sacked for incompetence. Over 40 years of horticultural training, experience and on-going study and it had not gone according to plan.
With self confidence and the belief in the saying along the lines of ‘An expert can be defined as someone who has made more mistakes than than a novice has made attempts’, I could have decided to have another go. Dundee City Councils results that year where not much better, the weather patterns and local soil conditions, aspect etc where all undoubtedly contributing factors. Having not been sacked, this years attempt (2023)I have proposed and it has been accepted to try a practice of creating a more permanent structural diverse colourful habitat for both people, and wildlife to enjoy. This is a practice I recommend to my private clients with ordinary sized gardens and will be discussed in greater depth in my next blog.
The colourful vibrant end result often late summer to autumn of wildflower seed mixes works best in larger landscapes and green spaces. Here the often bare ground followed by the prolonged weedy look until the vegetation comes into flower often goes unnoticed. When it starts to flower the beauty is then noticed and complemented. Even when the plants start to die back the skeletal framework of stems bearing seed heads is admired by naturalistic minded observers.
In the smaller private, ordinary garden sized setting finding an unobtrusive area to sow wildflower seeds can be difficult unless the owner is happy for a scruffy in your face look for a good part of the year until flowering commences. Often wildflower sowings are relegated to containers, raised beds or the boundaries of a garden so as not to interfere with the activities of the households from child and pet play to adult entertainment. Personally I would prefer to plant containers and raised beds with vegetables giving some healthy eating produce as well as pollinator resource for wildlife.
My next blog will state the case for planting for structural biodiversity. This provides an arguably much more permanent sustainable habitat for the biodiversity of wildlife, year round colour and interest for us to enjoy and after the first year much less destruction of soil habitat.