• Stop these immigrants spreading

    Monday, April 24, 2017 - 23:28

    It's late March and my fritillaries (Fritillaria imperialis) are growing inches every day, but already there are holes in the luscious leaves – and the culprit has to be the lily beetle (pictured). Bright red and rather attractive, they are little blighters.

    When I first discovered them I could not believe such gorgeous creatures could be the bad guys, but their voracious gobbling will strip the leaves of fritillary and lily before you can reach for the most noxious poisons in your cupboard.

    And you would be wasting your time because what you must do is to pick each beetle off the plant and slice it in two with your fingernail, or grind it under foot with your heel to really destroy it.

    The lily beetle has a cunning strategy: when it senses danger (which of course is you bending over to get a closer look) it will throw itself to the ground, upside down so that the black underside, so well camouflaged that you will never see it, allows it to escape and when you have gone it will climb back up the plant to start chewing again.

    So adapt your technique this way: creep up quietly and cup your hand beneath the beetle. Reach for it gently with your other hand and if it is quicker than you it will throw itself down, but will be caught in your cupped hand so you can then kill by your chosen method, nails or heel.

    Poisons do not work, and it is really important to catch these beetles every day as they bask in the sun on your best plants. This pest has no predators in this country and none of our poisons affect it.

    I naively thought my early vigilance would rid my plants of this nemesis, but the breeding cycle is quite quick so you must keep at it as long as you have breath in your body or the snow begins to fall, because brood after brood will be clambering up your stems without cease.

    Do not be tempted to throw it over to your neighbouring garden. We all have a duty to do anything we can to stop the spread of this immigrant, which is moving north at nine miles a year.