Slugs and snails still the same old curse in our lockdown gardens

PEOPLE SPENT more time tending their gardens last year but faced familiar pests and diseases attacking plants and veg, the Royal Horticultural Society said.

The charity’s 25th annual pest and disease ranking – based on inquiries from gardeners – reveals that slugs and snails, a mainstay of the rankings over the years, topped the list in 2020. It is the first time they have been in first place since 2017, as gardeners reported damage to crops such as potatoes and beans.

Vine weevils were in second place again but the box tree caterpillar, which strip box plants of their leaves, slipped to third place in 2020 from first in 2019, as reports of the invasive species fell 40 per cent.

The RHS said research had found box tree caterpillar spread slowed last year following rapid growth into northern England and Wales.

On the plant disease front, honey fungus was again top of the ranking, followed by pear rust, then leaf spot and canker of prunus.

The RHS said its gardening advice service had an 88 per cent increase in pest and disease inquiries last year as people spent more time in gardens amid the pandemic and lockdown restrictions.

Andrew Salisbury, principal entomologist at the RHS, said:

“The pests and diseases that gardeners commonly face on their plots has fluctuated over the last 25 years but some age-old problems persist.

“With gardens taking on a more important role in supporting wellbeing and the environment, it’s important that research into management and mitigation of them continues and our rankings help inform this focus. It’s also imperative that we continue to anticipate future threats.”

The top pests in 2020 were: slugs and snails; vine weevil; box tree caterpillar; ants; woolly aphid; glasshouse red spider mite; fuchsia gall mite; glasshouse thrips; rosy apple aphid; capsid bug and glasshouse mealybug.

The top diseases were honey fungus; pear rust; leaf spot and canker of prunus; rose black spot; bracket fungi; powdery mildew of prunus; blossom wilt of fruit trees; phytophthora root rots; rose powdery mildew and brown rot of fruit.