Figwort weevils

Figwort weevil adults and larvae feed on the shoot tips and flowers of figworts, buddleia, Phygelius and Verbascum.

Figwort weevil (Cionus sp.) on Figwort (Scrophularia sp.). Credit: RHS/Entomology.

Figwort weevil (Cionus sp.) on Figwort (Scrophularia sp.). Credit: RHS/Entomology.

Quick facts

Common name Figwort weevils
Scientific name Cionus and Cleopus species
Plants affected Figworts (Scrophularia species), buddleias - particularly Buddleja globosa, Phygelius species and Verbascum species
Main symptoms Small greyish-white beetles with black circular marks on the wing cases or slug-like beetle larvae present on the plants. Leaves at the shoot tips and flowers are eaten
Most active May-August

What are figwort weevils?

Figwort weevils are several closely related Cionus and Cleopus species of beetles. Both the adult weevils and the larval stage eat the foliage and flowers of Figworts, buddleias, Cape fuchsia and Verbascum 

Symptoms

Plants most commonly attacked by figwort weevil include Phygelius, Buddleja globosa, Scrophularia and Verbascum

  • Several species of weevil (Cionus and Cleopus species) partly eat leaves which can lead to foliage drying up, particularly at the shoot tips. There is also likely to be damage to flower buds
  • The adult beetles are black and greyish white and are up to 4-5mm (about 1/8in) long, with one or two black circular marks where the wing cases meet
  • The larvae are up to 6mm (about ¼in) long and yellowish-brown grubs with black heads
  • The larvae feed on leaves by grazing the surface of the leaf. The remaining tissues can dry up and become brown or white
  • Fully grown larvae spin spherical brownish cocoons on the plant stems in which they pupate, these can appear seed like

Control

Non-pesticide control

  • Where possible tolerate the presence of these weevils. Damage to plants is often minor and they rarely cause long term damage to the host plants
  • Where feasible the weevils and larvae can be removed by hand picking

Pesticide control

  • Pesticides are likely to be more effective on larvae than adults
  • Organic contact insecticides containing natural pyrethrins (e.g. Bug Clear Gun for Fruit & Veg, Ecofective Bug Killer). Several application of these short persistence products may be necessary to give good control
  • More persistent contact insecticides include the synthetic pyrethroids lambda-cyhalothrin (e.g. Westland Resolva Pest Killer), deltamethrin (e.g. Provanto Ultimate Fruit & Vegetable Bug Killer) and cypermethrin (e.g. Py Bug Killer)
  • The systemic neonicotinoid insecticide acetamiprid (e.g. Bug Clear Ultra) is also available
  • Follow label instructions when using pesticides
  • Plants in flower should not be sprayed due to the danger to pollinating insects
  • Inclusion of a pesticide product does not indicate a recommendation or endorsement by the RHS. It is a list of products currently available to the home gardener

Download

Pesticide for amateurs (Adobe Acrobat pdf document outlining pesticides available to gardeners)

Biology

  • Adult weevils overwinter in soil, leaf litter and other sheltered places
  • They emerge in May and June when they seek out host plants on which they lay eggs
  • There are two generations during summer between May and late August
  • When fully grown, the larvae spin spherical brownish cocoons on the plant stems in which they pupate
  • These cocoons closely resemble the seed pods of figwort


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