Dog owners taking part in “No Mow May” are being warned to keep an eye on hidden health risks as longer grass can expose pets to ticks, pollen and other seasonal irritants.
The annual campaign encourages households across the UK to leave lawns uncut throughout May to support pollinators and biodiversity. While the movement helps create wildlife friendly gardens, veterinary experts say it can also create a more challenging environment for dogs.
Leah Callaghan, a veterinary nurse at Butternut Box, said longer grass changes the conditions dogs are exposed to everyday by increasing humidity, dense vegetation and wildlife activity.
READ MORE: {{title}}
“‘No Mow May’ plays an important role in supporting pollinators and encouraging natural habitats, but it also changes the ground level environment where dogs spend a lot of their time,” Leah explained.
“As grass grows longer, it can hold onto more pollen and plant material. For some dogs, especially those with sensitive skin or allergies, this can contribute to mild irritation such as itching, paw licking, skin redness, sneezing, or watery eyes.”
She added that dogs naturally explore grassy spaces, increasing their contact with seasonal allergens during walks or time spent in the garden.
“This doesn’t mean longer grass is harmful in itself, but it can increase exposure to seasonal allergens for some dogs. A bit of awareness during late spring and summer can help owners spot and manage symptoms early.”
Leah also warned that longer grass can become a hotspot for parasites including ticks and harvest mites.
“Ticks in the UK, such as Ixodes hexagonus, or hedgehog tick, Ixodes ricinus often called the sheep tick, and the less common Dermacentor reticulatus, can be found in grassy or wildlife rich environments, alongside seasonal parasites like harvest mites.”
She said ticks are most active between March and October and are commonly found in long grass, woodland and areas populated by wildlife such as deer and sheep.
“They can be very small before feeding and easy to miss, but once attached, they swell and become much more noticeable.”
According to Leah, thicker vegetation can also attract more birds and small mammals, increasing the overall activity within gardens and outdoor spaces.
“Increased plant density can also encourage more wildlife activity, including small mammals and birds, contributing to a more active ecosystem overall. For dogs, this means a higher chance of encountering parasites or coming into contact with organic material that isn’t always visible.”
She added that reduced visibility in longer grass can make hazards such as sharp stems, litter and grass seed heads harder for owners to spot before dogs encounter them.
To help reduce risks during “No Mow May”, Leah advised owners to check their dogs carefully after walks or garden play, paying particular attention to the ears, collar area, paws and armpits where ticks commonly attach.
“Using regular flea and tick prevention is important during warmer months, especially for dogs spending time in long grass or woodland areas,” she said.
Leah also recommended rinsing or wiping dogs down after outdoor activities to remove pollen and grass residue, particularly for pets with sensitive skin.
“Regular grooming is especially helpful at this time of year, as it removes debris like grass seeds and makes it easier to spot any changes in your dog’s skin.”
Owners are also being urged to watch for signs including scratching, excessive licking, swelling, watery eyes or head shaking.
“If you notice anything unusual, such as itching that lasts more than a day or keeps coming back, swelling, or changes in behaviour, it’s always best to speak to your vet early.”
Leah added that if owners discover a tick attached to their dog, it should be removed carefully using gloves or a tick hook rather than pulled directly from the skin to reduce the risk of infection.
