Get Ready for Maize Harvest

The 2025 growing season has reminded us once again that no two years are ever the same in farming. A warm and settled summer has pushed maize crops on at an exceptional pace, with harvest expected to be several weeks earlier than normal across Northern Ireland.

High levels of sunshine and above-average temperatures in July and early August have accelerated cob formation and starch deposition. Many crops are now moving quickly towards maturity and growers need to be ready for the clamp sooner than anticipated. Where drilling was completed in good time and seedbeds were well prepared, crops have benefited from the warmth, achieving excellent plant height and strong cob fill.

The key to making top-quality maize silage lies in harvesting at the correct stage of maturity. The target dry matter (DM) is typically 30–32%, with cobs at the half to two-thirds milk line stage. Crops that are taken too early risk low starch content and poor feed value, while delaying harvest can result in overly dry material that is difficult to consolidate, increasing the chances of aerobic spoilage.

With this year’s accelerated growth, maize crops may reach the desired maturity window by early to mid-September in some cases – a full two to three weeks ahead of the long-term average. Now is the time to start walking fields, splitting cobs and monitoring starch development carefully.

A fast-moving harvest means clamps must be ready in good time:

• Clean out old silage and waste material to reduce the carryover of yeasts and moulds.
• Consider additive use- inoculants with strong heterofermentative strains such as Magniva Platinum Maize can greatly aid stability.
• Consolidate well and sheet immediately – good fermentation is only achieved when oxygen is excluded quickly.

The Magniva Maize range enhances silage preservation, stability and feed quality. Specifically formulated for maize, it speeds up fermentation to protect crop nutrients and reduce dry matter losses, which leads to more usable silage and improved farm efficiency. The product is distinguished by its patented bacterial combination of Lactobacillus hilgardii and Lactobacillus buchneri, which work together to provide excellent aerobic stability—enabling clamps to be opened sooner and reducing heating, mould and yeast activity at feed out. This results in significant reductions in dry matter losses, improved palatability and higher feed value for livestock.

Well-grown maize silage remains one of the most valuable forages available to dairy farmers. Its high starch content helps drive milk yield and butterfat, while its slower rumen breakdown complements high-quality grass silage. The expectation for this harvest is particularly promising – both yield and quality look strong, with energy levels potentially higher than average due to the long, sunny ripening period.

While the early harvest is a welcome outcome of favourable weather, it brings with it the challenge of being well prepared. Contractors will be in strong demand earlier than usual, so it is important to give them plenty of notice on when your crop is ready. To find out more about harvesting your maize at the correct time contact your local Fane Valley Agronomist or call 028 9261 0485.