When the rain doesn’t come: Smart grazing in tough conditions

During one of the driest seasons on record, keeping grass in the cows' diet can be challenging.

Reflecting on the season, the dry spell resembled that of 2022, but an exceptionally dry spring had intensified the challenge.

Grass growth plummeted across many farms, with average covers falling below 2,000 kg DM/ha – and in some cases, as low as 1,600–1,700 kg DM/ha.

Farms involved in our Forage for Knowledge initiative struggled and some stopped measuring altogether, suggesting the true average may have been even lower.

Despite these conditions, certain regions managed to keep grass in the diet, if not fully grass-fed.

Green paddocks stood out against neighbouring fields turned brown, underscoring the value of grass utilisation.

Piers Badnell, consultant at Pasture to Profit, highlighted that grass remains a key driver of profitability, reducing reliance on costly supplementary feed and the labour and machinery it requires.

He referenced consultant Sean Chubb’s experience in New Zealand, where extending grass availability during drought had proven critical.

In late summer, Piers visited Anthony Mitchell, herd manager at Wolfhall Farm – an AHDB Strategic Dairy Farm and Forage for Knowledge contributor – who shared his approach to navigating the season while keeping grass in the diet.

Anthony said:

“We received just 125 mm of rain up to the end of summer, with only 22 mm falling in August.”

The farm sits on greensand soil, which can be challenging – bottomless when wet, but quick to dry and carry cows after just a few days without rain.

Anthony described recent weather patterns as increasingly extreme, with long blocks of wet, dry and cold conditions becoming the norm.

Piers said:

“Dry weather began in March, prompting Anthony to act early. Growth rates hovered around 30 kg DM/ha, well below the expected 50 kg DM/ha.

“To protect average cover, he extended the first grazing round to 19 April and avoided dropping cover to the usual 1,950 kg DM/ha at balance day, instead maintaining it above 2,150 kg DM/ha.”

By late April, round length reached 28 days. Grass began to increase in the diet, allowing concentrate to be removed, though no surplus was available. Concerned about autumn feed, Anthony purchased hay as a safety net.

From April to early June, cows grazed 3,500 kg DM/ha entry covers, with average cover around 2,600 kg DM/ha.

Despite the lack of rain, Anthony maintained grass in the diet through tight allocation and careful residual management.

Piers said:

“A brief rain event in mid-May spurred growth to 80–90 kg DM/ha, but the boost lasted only 10 days.

“Round length was held at 30–35 days to conserve moisture, with growth stabilising at 55 kg DM/ha.”

In June, two-thirds of the platform were pre- and post-mowed to manage heading.

Thanks to moisture retained from May, grass began to recover. However, by the end of June, growth dropped to 20 kg DM/ha, and round length extended to 80 days.

Pressure mounted as autumn-calving cows continued milking until mid-July.

“By mid-July, our round length reached 120 days, with average cover at 2,120 kg DM/ha. The cows received a balanced diet of grass, rape and turnips, concentrate and silage.

“This strategy helped us endure the peak heat of mid-July, with temperatures in the low 30s.”

On 26 July, round length was reduced to 100 days, then shortened by 20 days every five days following 15 mm of rain and cooler temperatures.

Grass growth matched demand at 20 kg DM/ha and paddocks began to green up, allowing for quality third-leaf grazing.

By early August, round length settled at 60 days with growth at 25 kg DM/ha.

Despite a dry forecast and high temperatures ahead, Anthony remains confident, noting he can manage for 24 days without concern for the rest of the platform.

Concerns about stalky grass and seedheads are minimal. Anthony emphasises that clearing and cleaning up in late June mitigates most issues.

While 1–2% of tillers may head a second time, the base still contains green, three-leaf grass, and any brown material will rot away in autumn.

Anthony said:

“My decision-making relied on long-range weather forecasts, plate metering every 10 days, and visual assessments of leaf appearance.

“I monitored ryegrass plants closely, understanding that even smaller leaves under stress can signal readiness for grazing.”

Anthony’s approach to dry weather management centres on maintaining correct round length, average farm cover, and hitting residuals.

At the time of writing, Wolfhall Farm maintained an average cover of 2,175 kg DM/ha, with 8 kg DM of grass in the diet and a platform ready to respond when rain returns.

His proactive strategy has kept grass in the diet, reduced reliance on supplementary feed, and positioned the farm weeks ahead of where it might have been without early intervention.

As Anthony puts it:

“Grass utilisation and cost of production drive profit.”

The summer season prompted action that made all the difference.