Expert agronomist advice on growing grass crops this season

Unpredictable weather patterns from season to season are emphasising the need for farmers to grow resilient and quality grass crops that can withstand significant changes in temperature and rainfall.

The last 12 months encapsulates this perfectly. 2024 delivered one of the wettest springs in recent memory, with most farmers unable to apply fertiliser or slurry until early April.

Fast forward a year, and March 2025 has been one of the driest on record, with fertiliser and slurry applied in good time, but grass growth slowing due to a lack of moisture and cold overnight temperatures.

AHDB data emphasises this, with average rainfall in March 2024 approaching 100mm, while the same month this year it reached just 30mm.

The weather is constantly changing, but what can farmers do to take a long-term approach to try and mitigate these issues, and what are the main challenges and opportunities this season?

Origin Soil Nutrition’s range of Enhanced Efficiency Fertilisers can offer grassland a wider selection of nutrients that are proven to improve grass quality © Origin Soil Nutrition

We spoke to six nutrition agronomists from Origin Soil Nutrition to get a picture of the biggest challenges facing grassland farmers this year.

England – Tom Wells and Hester Hardy

From left to right: Tom Wells and Hester Hardy – Lighter first cuts for grassland mean a greater emphasis on getting following nutrition right © Origin Soil Nutrition

Farmers should be preparing for lighter first cuts due to the drier conditions and this puts greater emphasis on getting the nutrition correct for following cuts, so ensuring grass growth and quality is paramount.

Tom begins: “First cuts are likely to be delayed, and they will be much lighter than farmers would usually expect.

“Ensuring the clamp is full by the autumn will mean optimising nutrition for the second, third and fourth cuts to meet herd demands.

“Balanced nutrition will play a key role here and tailored grassland fertilisers will supply crops with the nutrients required.”

Hester says: “A further consideration for farmers should be the potential of higher residual nitrogen levels in the soil as the lack of moisture will have limited uptake for first cut crops.

“Any subsequent applications should take this into account and is something that farmers nationwide should be mindful of to avoid over application.”

Soil sampling data can be used to influence crop nutrition requirements and maximise grass quality © Origin Soil Nutrition

Scotland – Julia Andrews and Abby Kellett

From left to right: Julia Andrews and Abby Kellett – Grass is the cheapest form of feed, so taking extra time to ensure nutrient balances are correct is essential for this season and longer term © Origin Soil Nutrition

The potash scenario should also be a consideration for farmers in Scotland. At the end of a dry spell, mineral analysis would indicate a high level of potash in grass due to the stress the crop is under.

Abby says: “In dry conditions, grass will consume whatever potash it can to offset the stress, this brings into focus the need for sodium to maintain the right sodium and potassium ratio. Without this, further problems are possible.”

This nutrient relationship is crucial to avoid a greater risk of hypomagnesaemia (grass staggers).

Sodium is a common deficiency across UK soils, but it has a vital role in improving grassland quality and palatability.

Farmers should be looking to specify the quality parameters of the grass they’re growing to suit their livestock.

Julia agrees: “Grass is the cheapest form of feed, so taking extra time to ensure nutrient balances are correct is essential for this season and longer term.

If you have feed samples from 2024, working with a feed advisor and FACTS qualified agronomist can help tailor inputs to grass requirements.”

Wales – Owain John and Guillaume Franklin

From left to right: Guillaume Franklin and Owain John – Prioritising quality over quantity is key, and nutrient balances within the soil profile have a huge influence on forage quality © Origin Soil Nutrition

Prioritising quality over quantity is the key message from farmers across Wales and into the south west of England. Nutrient balances within the soil profile have a huge influence on forage quality, as Guillaume explains.

“Consider what you’re trying to optimise when nutrient planning.

“Is the pH correct; does the crop require all the macronutrients currently being applied; are there low micronutrients that could influence better crop response; is my current strategy in line with the goals?”

The balance between different nutrients will have the biggest bearing on the quality of the forage or grazed grass grown. Nutrients work in synergy, so when one is deficient, it reduces the efficacy of others that rely on it.

The addition of selenium and cobalt can improve animal health through better forage quality and remove the need to rely on licks or supplements at the end of the season.

“Products such as Origin’s SweetGrass Plus have added selenium and cobalt,” says Owain.

“Selenium is required for improved fertility and boosts liveweight gains, while cobalt is essential for vitamin b12 formation, and deficiencies will lead to an increased risk of infection and reduced performance.

“Tailoring inputs with a prescription fertiliser will maximise applications and improve quality this season and beyond.”

Guill says a key part of nutrient planning for these will be using data from soil, forage and slurry analysis to determine the correct inputs to reduce offtake implications.

Potash applications, in addition to slurry, should also be a consideration for farmers.

“Many farmers will use slurry as the primary source for potash after each cut, but it may not provide the crop with the full requirement according to RB209 advice. Some results seen this year highlight a greater demand for potash.”