Phacelia tanacetifolia

Phacelia is annual upright and multi-branched dark green, hairy, flowering plant. The leaves have a feathery appearance. Flowers colour is lavender to pale blue or white. The roots are shallow, with dense, lateral side roots. Seeds are small 2mm in size and will only germinate in the dark. Used as soil-improving green manure and break crop.



  • establishes quickly, sow from spring until autumn after the risk of frost.
  • suppresses weeds, due to its fast establishment and rapid growth
  • large biomass plant - produced in 14 weeks
  • incorporated into the soil to get maximum benefit.
  • biomass breaks down quickly after mulching due to the fine leaf structure, great for direct drilling
  • great cover crop for improving soil quality
  • not deep-rooted but has dense shallow roots which condition the top 3-4cm of soil. The root system adding an extensive amount of organic matter 
  • prevents nitrogen leaching - the root mass is very reactive at catching nitrates in the soil before they can leach into the groundwater
  • attractive to honeybees and bumblebees and other beneficial insects 
  • good for honey production - a great source of pollen and nectar 
  • can flower and set seed quickly - flowering 6-8 weeks after emergence and will continue to bloom for 8-10 weeks as long as 13 hours of daylight
  • frost tolerance - can survive very mild winters, prolonged frosts will kill the plant
  •  mostly free from problems with pest and disease. 
  • comparable to buckwheat it is more persistent and tolerant of drought and cold temperatures



  • seeds only germinate in darkness, need to be shallow sown and harrowed or rolled well to cover
  • a long-day plant requires a minimum of 13 hours of daylight to initiate flowering
  • vigorous, it should not be used in mixtures with slower growing species.




  • only combined in a mix with other fast establishing species like mustard, the annual clovers or buckwheat.


Suggested sowing rate 

10kg per ha.

sow from spring until autumn after the risk of frost


Mixture Sowing Rate suggestion

0.625 - 1.25kgs per ha



2 - 3t DM per ha.