The average area of forage maize grown in Ireland between 2019 and 2022 was 15,000ha, an area that may well be maintained in 2023.

This is especially so, given that silage stocks are low on many livestock farms at the present time.

The cost of growing maize has increased significantly in the last two seasons. The total variable costs for growing maize in the open in the Teagasc ‘costs and returns 2023’ is €2,246/ha.

Plastic will add approximately €600/ha to this cost. Based on these costs, maize grown in the open yielding 12t dry matter DM/ha would cost €187/t DM and maize under plastic yielding 14t DM/ha would cost €203/t DM. 

Growing maize under plastic aids establishment, improves quality and offers an insurance against poor weather conditions, but its benefits are reduced if planting is delayed into May.

Both oxo-biodegradable plastic and bioplastics (compliant with single use plastic directive) are available on the market.

The single use plastic directive prohibits the use of oxo-biodegradable plastic but farmers are free to ‘use up’ the old oxo-biodegradable plastic, if it was manufactured prior to the effective date of prohibition (July 2021). 

Varieties of maize

The Department of Agriculture Food and the Marine (DAFM) recommended list for 2023 gives details of varieties that have completed a minimum of three years in trial in Ireland.

This year sees the department pushing ahead with a list of varieties, grown under uncovered conditions. This is the first time that such a step has been taken since 2015.

Ambition is provisionally recommended. Growers should note that it was previously recommended in 2015. The variety delivers high relative yields plus good DM and good starch content. Ambition is a medium maturing variety.

Also, provisionally recommended for 2023 is Prospect. This is a good yielding variety with good starch content. DM contents are also good. Prospect is a medium maturing option.

And, finally, Resolute is a very high yielding variety with moderate starch content. It has a low DM content and is a late maturing variety. Resolute has received a provisional recommendation for 2023.

Uncovered trials, which were discontinued in 2014, were recommenced by DAFM in 2020 in response to the Single Use Plastic Directive.

They comprise up to 20 varieties annually and are grown at four sites per year. The varieties are assessed for their suitability under Irish conditions for DM yield, DM content, starch content and other traits.

The recommended list only contains varieties that have shown excellent performance under Irish conditions, which are accepted as being unique and come with specific challenges to growing the crop successfully.