Growing maize under plastic has been around for many years,but it is a significant investment at £94/ha more than establishing maize without plastic, and therefore its use should be reviewed periodically.
Aller Barton Farm in Cullompton Devon has heavy soils, and it can be difficult to establish cereals and grass in the autumn behind the maize, especially in a wet autumn. The risk of an autumn crop failure on such challenging soils can put a significant dent in crop gross margins. Therefore,for many years Michael Cooke has strategically grown maize under plastic in some fields to ensure that the crop is harvested early and wheat and grass leys establish successfully before the winter.
This year the maize has been drilled in 2 periods – some early on 11th April and the remainder on 1st May.On each date some fields were drilled with and without plastic.
Michael has kindly agreed to us doing some monitoring and analysis before and during harvest this year in order to accurately determine the return on investment of drilling with plastic on his farm.
But as a taster we have some photos to show you the progress of the crops to date:
This is the maize that was drilled without plastic on 1st May. It has established well, weed control is good and currently there are 6 leaves on the plant.
The maize drilled under plastic at this time has not yet broken through the plastic and therefore we have not included a photo. But again, weed control is good, but the plants already have 7 leaves, so when they do break through then we expect the crop will look slightly further ahead.
This photo shows the maize that was drilled on 11th April with plastic,which is quite breath taking. The “knee high by 4th July” rule is pretty much blown out of the water!!! Again, weed control is good and the crop has 12 leaves already.
Within this field there are 2 rows of maize that have not had plastic, and this photo shows very clearly the difference between the crops in the same field at this point in time. The area without plastic is 3 leaves behind at present and significantly shorter.
Of course, just because the crops are well ahead at this stage does not mean to say that the yields and starch levels will be higher by the time the crops are harvested, or how much sooner the harvest date will be. But we plan to measure this and feedback to you later in the season so that you can see if it is worth considering on your farm.
We will look at total yield and starch percentage, and quantify this in terms of its effect on subsequent diet cost, so that we can see what the return on this investment is likely to be. So watch this space!
We would like to thank Michael for allowing us to do this piece of work on his farm this year – and of course the excellent modelling of his legs to demonstrate crop height!!
