Assessing maize (c) Breeze & Freeze

The 2012 maize growing season has been a challenging one with rain hampering grass and wholecrop harvests and the lack of sunshine and heat limiting forage maize growth, writes Neil Groom, technical director for Grainseed.

However, warmer weather in the past 10 days in many areas has allowed maize crops to start starch laydown and although maize harvest has been delayed the majority will clamp mature maize, albeit later than normal.

This year we have sampled maize under plastic at the Scottish Agricultural College in the same field as the normal sample of Picker not sown under plastic. These were drilled at the same time, whereas other fields on the farm were sown at the end of March under plastic for an early harvest to allow grass re-seeding for Scotgrass next May. These March-sown crops are ready for harvest now.

Soil structure has been key to success for maize this year. Anywhere where there is compaction within the soil profile or any parts of the field lie wet, maize has struggled.

Remember maize silage quality is optimum at 30-35% dry matter when the sugars produced by photosynthesis are stored as starch in the grain. We want the grain to be ripe so that when you squeeze a grain between your fingers only the smallest drop of moisture can be seen. Many crops are milky ripe meaning they are three to four weeks from harvest.

Bill Blake, sampling for Farmers Weekly in Devon, has noticed a big change in crops in the past 10 days: “Last week grains were swollen, but had no starch but 10 days of warmer temperatures have altered the crops significantly.”

 Site Drill date  Height above sea level (m)  Crop dry matter  13 September (%)
Petworth, Sussex 18 April 50 25.0
Harleston, Norfolk  4 May 30 22.5
Crediton, Devon 5 May 118 23.3
Ticknall, Derbyshire 12 May 67 19.8
Llandeilo, Carmarthenshire* 4 May 32 19.9
SAC, Dumfries, Scotland (plastic) 26 April 45 20.9
SAC, Dumfries, Scotland 26 April 45


* Variety Es Picker, all other sites are Es Ballade. Variety under plastic Es Marco

More on this topic

Keep up with this year’s maize harvest on our dedicated Maize Watch page