For our fields, the rain is welcome. For our horses, however, the transition from prolonged drought to wetter, cooler conditions deserves careful management.
July 2026 was exceptionally dry. England and Wales recorded their driest Julys on record, while southern England experienced its driest month of any month in a rainfall series stretching back to 1836. England received just 6.5 mm of rain during July, only 10% of its long-term average, while southern England received just 1.9 mm. Around half of England and the whole of Wales were affected by drought conditions. Now the weather pattern is changing. Rain has returned to parts of Britain, with the Met Office forecasting showers and, in some areas, heavier downpours and thunderstorms.
It might seem that greener fields can only be good news. But for horses, rain following drought can create a very different nutritional environment surprisingly quickly.
What Happens to Grass During a Drought?
Grass does not simply stop changing when the ground dries out.
During prolonged dry, sunny conditions, pasture becomes stressed. Growth may slow dramatically, but the plant can continue producing and storing soluble carbohydrates. Short, drought-stressed grass can therefore be more nutritionally complicated than its brown, sparse appearance suggests.
This matters because horses do not necessarily see a bare summer field in the same way we do. They can graze remarkably close to the ground, accessing the lower portions of plants where carbohydrate reserves may be concentrated.
Our previous work on summer grazing has highlighted the importance of environmental conditions in grass sugar accumulation and the particular risks associated with stressed and overgrazed pasture.
Why Rain After Drought Can Be a Problem
When water finally becomes available, drought-stressed grass can respond rapidly.
Suddenly, a paddock that has looked dry and relatively unproductive can begin producing fresh green shoots. For a horse, this represents a potentially abrupt dietary change.
Young regrowth can be highly digestible and comparatively low in structural fibre, while supplying readily fermentable carbohydrates. Horses may also increase their grass intake because the new growth is particularly palatable.
The important point is that the risk does not necessarily disappear because the drought has ended. It changes. During the drought, owners are managing dry pasture, reduced forage availability, heat and potentially concentrated grass sugars. Following rainfall, the challenge can become rapid pasture regrowth and a sudden increase in fresh forage intake.
For the digestive system, that rapid transition matters.
The Horse’s Gut Likes Consistency
A horse’s digestive system is remarkably effective when given what it evolved to process: frequent amounts of fibrous material consumed over many hours. It is less enthusiastic about abrupt dietary change. When more starches and water-soluble carbohydrates escape digestion earlier in the gastrointestinal tract and reach the hindgut, they become available for microbial fermentation. Rapid changes in substrate availability can alter the hindgut environment and microbial populations. That is why changes in grass, forage and concentrate feeds are normally introduced gradually.
Summer weather can effectively make some of those changes for us. One week a horse may be picking through dry, stemmy pasture and relying heavily on supplementary forage. After rain and warm conditions, the same paddock can start producing palatable new growth.
For horses already sensitive to dietary change, rich grazing or metabolic problems, that transition requires particular attention. High grass sugar intake is especially important in horses predisposed to laminitis or insulin dysregulation, while digestive disturbance can also present as changes in droppings, bloating, discomfort or altered behaviour.
So what can owners do?
Management Comes First
Following significant summer rain, keep watching the field rather than assuming the difficult part of summer is over. Rapidly emerging green shoots are a reason to reassess grazing, particularly for horses that are overweight, insulin dysregulated or have a history of laminitis.
Depending on the individual horse, practical measures may include limiting grass intake, strip grazing, using an appropriately fitted grazing muzzle, maintaining adequate suitable forage and avoiding sudden changes to supplementary feeds.
Most importantly, watch the horse as well as the grass.
Changes in droppings, appetite, demeanour or performance deserve attention. Signs associated with laminitis, colic or significant digestive pain require veterinary advice rather than simply adding a supplement. Alongside good management, however, nutritional support can help – and this is where choosing the right product for the situation becomes important.
