Garden Pests Series: L…

Thoughts and musings

Garden Pests Series: L…

Lewis | April 21, 2015 | 0 Comments

…is for Lily Beetle.

We’re quickly approaching the halfway point in our Garden Pest Series; of the 26 posts that this series will consist of, this particular post is number twelve. For me, it feels like the time has flown by; I have really enjoyed writing these and I hope you have equally enjoyed reading them! This post is about the lily beetle, or the scarlett lily beetle as it is sometimes referred to. It is quite the garden pest in the UK in particular, so let’s not use up any more time on online blog pleasantries; let’s get down to the bare bones of this issue!

Lily beetles are common in the UK, especially in our particular region, the South East. However, they have been reported in other areas of the UK, such as Scotland, Wales and parts of Ireland. This isn’t the best of news, as this invasive species is a particular scourge of the gardener, including one of our garden maintenance operatives featured in the photo to your left! They were first recorded in the UK during the Second World War and have been here ever since.

However, unlike other garden pests that are sometimes hard to see or determine, the lily beetle is much more noticeable to the eye; these bright red insects are very distinctive. Not only this, to see physical evidence of their damage, look for holes in the leaves of certain plants as well as the stems and the flowers themselves. These are caused by the lily beetle during the larvae stage of their life cycle, which are black and slimy in appearance.

There are more destructive to certain plants than others; if you have lilies (Lilium) and/or fritillaries (Fritillara) in your garden, you should be more concerned, as they thrive on these plants and others from the same biological family, Liliaceae. It is on these plants that they lay their eggs; they have been known to do so on other plant species when lilies and fritillaries are absent, but fewer eggs are laid and their rate of survival is reduced.

However, this tiny bit of good news is only a flash in the plan. These pesky little blighters can be very destructive. The lily beetle larvae can often be found on the underside of the leaves, where they commonly feed from the tip of the leaf up to the stem. They can also repopulate quickly; adult lily beetles will continue to feed and mate from the Spring, all the way through to the Autumn, with females laying eggs on the underside of leaves which hatch into larvae – grubs which are red/orange in appearance – only a few days later. This larvae, if it survives until the Autumn, will retreat to the soil over the winter and return to the surface the following Spring as adults.

The worst-case scenario is, of course, if you have a garden full of lilies! However, you should be vigilant of the lily beetle no matter the plants species you may have. Luckily, there is a wide range of treatment courses available, including chemical. Natural fatty acids, surfactant-based products and Pyrethrum are all effective agains the lily beetle. As always though, we at Oakleigh Manor recommend you read manufacturer’s instructions before using chemicals and take the necessary PPE precautions.

There are plenty of organic means of treatment if you prefer, though. You can always remove larvae by hand to stop infestations becoming established. Netting also prevents adults from moving between plants. To avoid adults emerging in the Spring, repotting lilies and fritillaries in fresh soil is also a popular choice. Finally, there are a range of natural predators and parasites of the lily beetle which will help somewhat with control. As far as prevention of possible infestation goes, the only advice we can offer you is to check plants regularly and to encourage insect-feeding birds into your garden. This can be done by providing them with feeders during the colder months and nesting boxes during the warmer ones.

Voila! There you go; another cracking post by Oakleigh Manor’s marketing team.