Maize Watch: Checks necessary as maturity races ahead

Growers are being advised to check their maize fields twice a week as maturity races ahead.

The recent drier weather and autumn breezes have pushed maize maturity forward as the crop naturally dries down towards harvest.

Neil Groom, technical director for Grainseed, says the crop should be at an optimum dry matter of 32% for clamping and feeding.

Mr Groom advises growers to look at the plant as well as the cobs to determine harvest date.

See also: 5 steps to make the most of maize in feed

“Ideally the leaves up to the cob height should be dying back and those above should still be green to provide the sugars for rapid fermentation in the pit. The grains should be fully mature with only the smallest droplet of moisture being able to be squeezed from the base of the grain.”

He says farmers should keep contractors informed of how crops are progressing and get organised before they arrive on farm.

“Clear space in front of the pit to allow easy tipping and have the side sheets hung before they arrive,” he says.

Toby Tibbenham, sampling for Farmers Weekly near Harleston in Norfolk, says his crops are looking good and should be cut next week.

“The field I am sampling is the lightest and so the dry matter has increased by 4.7% this week, but the more-bodied soils are still green to the floor and I can squeeze a lot of juice from the grains. I will cut the sample field first and put on the bottom of the clamp and the greenest field on top.”

Top tips ahead of harvest:

  • Be prepared to put an extra tractor on the pit for rolling. You cannot overdo this because you need to squeeze all the air from the silage.
  • The pit should be loaded in shallow layers no thicker than 12-15cm and the use of compactors can help increase density.
  • Check the chop length of the first loads of maize into the clamp to ensure they meet your requirements.
  • Ruminants need some scratch factor in the diet from their forages, so a longer chop length of 18-20mm is desirable, but this is harder to consolidate especially if the crop is dry.
  • Review your silage experience from last year. Did you experience losses from moulds or have problems with mycotoxins in the diet? The use of a silage additive can reduce these risks and improve palatability and intakes.
  • If losses were just on the silage surface and shoulders, increased rolling and the use of oxygen barrier film will all help.
  • Forage is your cheapest winter feed so investing in improving its preservation will improve feeding and production throughout the winter.
Maize maturity 


Drill date

Height above sea level (m)

Crop dry matter 9 September 

Increase from last week

Petworth, Sussex

27 April




Harleston, Norfolk

30 April




Crediton, Devon *

22 April




Ticknall, Derbyshire

25 April




St Clears, south Wales*

24 April




SRUC, Dumfries, Scotland PLASTIC

6 April



+ 4.4

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