Wimbledon’s high gardener is on the hunt to nab pesky caterpillars

Wimbledon gardeners have had to fend off the threat of very hungry toxic caterpillars that can trigger severe skin rashes, deadly asthma attacks and even blindness.

Thousands of tiny hairs on the caterpillars, which feed off oak trees, contain toxins that can cause vomiting, dizziness, fevers as well as skin, eye and throat irritations.

Experts have warned the pests – which originate from the Oak Processionary Moth –pose a threat to humans, pets and plants and that people should not approach them or their nests, with the exposure risk highest in May and June.

A nest typically looks white before it turns brown and is ironically around the size of a tennis ball.

Britain has long been plagued by hordes of the insects who are said to have first appeared in the country in the early 2000s after arriving on a shipment of imported tree stock.

Wimbledon head gardener Martyn Falconer says his team in SW19 tackle moths in the spring before they get the chance to hatch into caterpillars which cause havoc at the Championships

Since then, they have been found in areas across London as well as in Kent, Berkshire, Surrey, Essex and Hertfordshire.

And the tiny foreign invaders have also appeared at SW19 – where head gardener Martyn Falconer and his team aim to create a typical ‘English garden’ for tennis fans to enjoy.

Mr Falconer said his team tackle the moths in the spring before they get the chance to hatch into pesky caterpillars and create havoc at the championships.

He added: ‘There are a few pests and diseases around like box caterpillars that we tackle.

‘Oak processionary moth is one that you have to be mindful of because you’ve got a caterpillar with some pretty nasty hairs and if they drop they can cause problems.

‘They’re dealt with in the early spring with some biological spray controls, it’s not a sort of nasty chemicals which we mist up into the trees.

‘If you catch them early in the spring then they don’t get to that stage when they turn into a caterpillar.’

He also revealed the tournament’s plans to go even greener by using peat-free compost for all its flowers within two years.

It comes amid an upcoming ban on peat compost to protect bogs, which take thousands of years to form and help fight global warming.

By the end of this year, gardeners will no longer be able to buy bags of compost containing peat, but they will be sold for trade use until 2030.

Mr Falconer added: ‘All of our compost is homemade so some refer to it as black gold, it is such a good product, better than anything you can buy in the nurseries peat-free.

‘We are doing trials at the moment to go completely peat-free on all our hanging baskets and petunias under two years.

The pests – which originate from the Oak Processionary Moth –pose a threat to humans, pets and plants, with their risk highest in May and June

‘We are completely peat reduced now, we have got about 100 modules and about 24 baskets that are peat-free and we are just trialling it to get the feed in and everything right so that the displays are as good.’

He also revealed gardeners are experimenting with using coffee grounds from staff canteens and other food and drink to add to the compost

But he acknowledged a warning by the Royal Horticultural Society that gardeners who use peat-free compost could be at risk of killing their plants by overwatering.

These new varieties of compost do not look ‘wet’ after watering, meaning the green-fingered may end up drowning their plants.

He added: ‘We have got to get it right the problem without having your peat is you lose that retention of moisture you lose a little bit of your elements of seeding in that growing media so we have just got to try and replicate that and get that right.’