Harvest update

Welcome to the third edition of the KWS UK email service, helping you to get the best out of our maize varieties.†

Featured this month:†

  • Harvesting tips/maturity indicator
  • Live heat unit service
  • Trials results update
  • Invitation to our demonstration site

Harvesting Tips†

Effects of harvesting too early

  • Lower yield
  • Reduced energy, starch and ME which results in lower intake potential
  • Higher risk of clamp effluent which will require a longer chop length
  • Poor dry matter intake and palatability resulting in acidic silage

Effects of late harvesting

  • Higher harvesting costs and increased field losses
  • Low digestibility and palatability
  • Excessive dry matter and poor clamp stability
  • Difficult clamp consolidation which will require a short chop length
  • Soil damage/compaction

†Harvest maturity indicator

Maturity indicator

Maize Heat Unit Service

KWS †provides a live ‘free to access’ service for all farmers and advisors, to assess maize heat units for their farm and region. The service is really easy to use;

  • Enter your postcode
  • Data shows the live 2016 heat units for your farm, compared to the long term average

Useful facts and recommendations:

A heat unit is calculated using formulae combining daily minimum and maximum temperatures, discounting mean values less than 10įC, the minimum temperature suitable for maize growth

  • Heat units are updated weekly, between April to October
  • Approximately 120 heat units are needed for a maize plant to fully emerge
  • Approximately 45 heat units are needed to form a new true leaf
  • Heat units do not account for radiation (sunlight), field aspect (north or south facing), or reflect likely sowing date

Early varieties (FAO 150 – 160) require around 2,100 heat units by the middle of September to reach maturity. Later varieties (FAO 180 – 210) need around 2,400 heat units.

Later maturing energy maize hybrids, used exclusively for biogas (FAO 240 – 260) require between 2,500 – 2,800 heat units, depending on drilling date.

Click here to access the service

Results from KWS Trial Sites

maize trial results 2016

KWS Maize Demonstration Site

If you would like to visit the KWS Office and demonstration site at Lydney in Gloucestershire please contact your local merchant.

Demonstration field includes:

  • Breeding demonstration
  • All current commercial hybrids
  • Population wheel
  • First look at all new hybrids before they are listed
  • Chemical demonstration
  • AD trial which includes all our current and new hybrids

Also available adjacent to the demonstration field is:

  • Anaerobic digester
  • Dryer
  • Dairy unit

Farm Visit
If you would like us to visit your farm, please email the office at