Dairy farmers growing forage maize can maximise cob yields and double their crop’s starch content by sowing maize under plastic according to Dr Simon Pope of Wynnstay. Sowing maize under a thin film of degradable plastic has several key advantages over conventional growing methods including increased yields, earlier harvesting and the ability to grow maize in marginal areas.  But it is the rapid development of a large root that is the key to unlocking the crop’s full potential. “Maize sown under degradable plastic grows much more rapidly at the beginning of the season thanks to the soil warming effect provided by the insulating layer of film,” Dr Pope explains.  “By raising the temperature of the soil, roots are able to develop more quickly giving young plants an early advantage over conventionally sown crops.”

Initial assessments using hybrid varieties from maize breeders Pioneer Hi-Bred, have shown that plants sown under a layer of degradable plastic have a 10 fold increase in root mass in early July compared to the same varieties grown in the open.

“Such a stark contrast in performance has a marked impact on final yields,” Dr Pope continues.  “In general, crops grown under a layer of film will achieve an additional two tonnes per hectare of dry matter.  The majority of this will come from significantly larger cobs.”

And with increased cob size comes an increase in starch content.  “The main reason for growing maize is to provide dairy cows with a year round supply of high energy forage,” Dr Pope continues.  “Crops grown under film mature earlier and have greater leaf area for a longer period of time during the longest and sunniest summer days so more sunlight is converted into sugar.

“These crops give increased cow performance and can also be harvested up to a month earlier.  This spreads the workload and helps bridge the gap at the end of the summer when most farmers have finished last year’s clamp and are still waiting for the new crop to mature.”

Increased root size has other advantages as well according to Samuel Shine, inventor of the Samco System which is used to sow maize under film.  “Larger roots allow plants to take full advantage of the nutrients in the soil so less fertiliser is required.”  For farmers growing maize on a large scale this factor alone can amount to significant cost savings.

Mr Shine also points out that plants with well developed roots will be more resistant to drought and very wet conditions.  “This mitigates the risk associated with unpredictable weather patterns and enables crops to produce consistent levels of starch and dry matter year on year.”

▲back to top▲