Wildflower Management: How to Sow

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Follow these simple steps to ensure you get the best display

When to sow 

You can sow your wildflower seeds in autumn or spring – spring may be a safer bet to ensure that the seeds are not waterlogged or washed away over the winter months. 

Later spring sowings may be more at risk from drought in the summer than earlier ones, not being so well established, but they will often recover to flower very late following wetter periods in late summer, a familiar pattern in recent years.

Ground preparation

There is no need to remove topsoil as you might with a perennial seed-mix; annual cornfield wildflowers grow quite happily in a richer soil.

In an area which is free of perennial weeds: 

  • Sowing should be done on bare soil. 
  • Dig or rotovate the soil to a spade’s depth, then rake level.

In an area with weeds or grass: 

  • Hoeing will take care of plots that only have annual weeds - give yourself at least four weeks to allow for repeat hoeings as weeds reappear. Perennial weeds are trickier, but on lighter soils a thorough digging and hand weeding should work on weeds such as nettles, docks and brambles. 
  • Perennial weeds that leave behind lots of tiny pieces of root or rhizome after hand weeding (e.g. bindweed, couch grass, ground elder and horsetail) are likely to remain problematic without an application of weedkiller. Spray off the vegetation with a glyphosate-based weedkiller, such as Roundup, 4-6 weeks prior to sowing. Allow the treated area to yellow and die back before sowing. 
  • Grass should be stripped back to reveal bare soil and the seeds sown on to this. 
  • If appropriate, a weed suppressing membrane or sheet of black plastic could be laid over the intended site in autumn and left in place until sowing time, but these are not aesthetically pleasing should your area be in a central location.

How to sow 

  • If the soil is particularly dry, soak with water 24 hours prior to sowing. 
  • Even large areas can be sown by hand quite easily, but it is important to get an even distribution. To help achieve this, try mixing the seed with a little silver sand (one part seed to five parts sand), which will make it easier to handle. 
  • Broadcast half lengthways and the remaining half widthways to ensure as even a distribution as possible across the sowing area. 
  • Rake the seed lightly into the soil - there is no need to bury it, just ensure that it is not lying on the surface. 
  • There should be no need to water, provided the ground was damp prior to sowing. However, if the surface of the soil dries before the seeds germinate, water the area with a sprinkler or a watering can with a rose on the end to give a fine spray. Apply a sufficient amount to wet the top 4-6cm of soil.