Calendula officinalis and Borago officinalis

Time of sowing


  • Field margins should be located in full or partial sun.
  • The border should also not be flooded for long periods.

Soil conditions

  • Flowers thrive best in poor soils. If the soil is too rich, weed pressure will be higher.
  • Take into account the weed pressure on the plot in the past. If it was high, extra attention will have to go to weed suppression.
  • The flower mixture should also be adjusted according to the type of soil (clay/loam/sand).

Timing of sowing

In general, it should be sufficiently moist and warm when sowing to allow the seeds to germinate.

  • Annual mixtures are best sown in spring (March - April), preferably April as it will be warmer by then. If the mixture contains only hardy species, it can also be sown in autumn.
  • Perennial mixtures are best sown in autumn (September - October). Autumn has a better chance of success because it gives the plants a head start on the weeds in spring.

Soil preparation

  • Remove dirt from the soil
  • In case of high weed pressure, ploughing can be a remedy
  • Make the soil sufficiently fine by tilling
  • About two weeks before sowing, establish a false seedbed (= this is preparing the soil for sowing, without sowing the mixture). In this way, the first weeds already germinate, which can then be worked in e.g. with the roto harrow. Note: if the soil is too dry, a false seedbed makes no sense, as the weeds will not germinate.
  • Then prepare the seedbed again.


  • Do not sow the seeds deeper than 1 cm
  • The recommended sowing density is 15 kg/ha (1 – 2 g/m²)
  • Divide the seed into portions to avoid running out of seed sooner than planned
  • Also make sure the seed is well mixed: seed sizes in flower mixtures can vary greatly (e.g. poppy versus sunflower). It is recommended to mix the seed with sand/wheat meal/cornmeal to achieve a more homogeneous sowing.
  • Roll the soil after sowing to ensure better germination.

Should you sow by machine or by hand? For areas under 0.5ha, it will probably be quicker to do it manually. This is because a lot of time often goes into adjusting the seeder properly due to the different seed sizes.

More practical info in this guide (Dutch).