Maize update

Published 9 May 14

During the 2014 season DairyCo’s Forage for Knowledge will follow four maize growers from across the country, to hear about their experiences. Today, farmers from Cornwall and Staffordshire talk about establishing the crop and why maize plays such an important role in their cows’ diet.

Matthew Roe milks 400 Holstein Friesian on the edge of Bodmin Moor in Cornwall and grows 150 acres of maize, of which 100 are under plastic.

“We are in a marginal area for maize growing and had several years of poor crops, where yields did not justify the cost of growing it. As high-quality forage is crucial to keep our cows performing throughout the year and maize being so important to our ration, we decided four years ago to grow the maize under plastic.

“Lower sites are planted without plastic, but in order to guarantee the yields and quality we need, the higher sites are planted with plastic. The increase in tonnes of DM/acre and the high-quality starch cover the additional costs of the plastic. It’s kind of an insurance policy, so even in the poor years we are guaranteed a certain amount of high-quality maize.

“This year we were about two weeks late in planting the maize under plastic because of the wet ground conditions – it went in on 15 April. Shoots were up within seven days. Again, we were two weeks late planting the traditional maize, on 4 May.

“The plastic is all about raising the temperature. Two weeks ago, we took soil temperatures and they were as follows: for the maize under plastic it was 22°C, for the traditional maize it was 15°C and for the grassland it was 12°C.

“We usually harvest the maize under plastic in early October, meaning we can get a wheat crop in if it’s part of the rotation. In a normal year, the cobs under plastic are ripe by early September but the plant itself is still wet and green, so we have to hang on for it.”

Adam Ball milks 200 Holstein Friesian cows in Staffordshire and grows 54 acres of maize

“We planted our maize on Monday (5 May), which is about the normal time of year. Although we haven’t been too badly affected by conditions this spring, it was a different matter when we harvested last November.

“We had some very wet conditions and one field in particular was badly churned up - our contractor got just about every machine he had stuck in it! In that field, we went through first with a subsoiler this spring, to level out the field and get it to drain better. Three weeks later, as with all the other maize fields, we ploughed it, subsoiled again and then went through it with a power harrow.

“We drilled all fields at 42,000 seeds/acre, fertilising down the spout at 50kg/acre of Diammonium phosphate (DAP), and then rolled. We’re aiming to go with a post emergence herbicide.

“We used two extra-early maturing varieties which performed well last year, even though I’m aware that it was an exceptionally good year for maize. We’re on the cusp of a marginal area here and don’t really have the heat units, so we struggle to get the crop off in October. It’s usually November by the time we harvest the maize.

“Maize is excellent alternative forage for our high-yielding cows. We usually feed a 50:50 grass silage: maize silage diet throughout the winter, but this winter it was more like a two-thirds maize diet, due to last year’s bumper crop. I’m sure it contributed to a rise in milk yields across the board.”