Our Pest Control Expert, Julian Ives, has spent many years advising commercial growers and gardeners on the subject of safe and efficient natural pest control treatments.

Here he shares his experience on the problems Vine Weevil can cause in the garden and how to get the best from the Vine Weevil Killer we supply...

Using Vine Weevil Killer
Nemasys Vine Weevil Killer contains the nematode Steinernema kraussei. This is a nematode that kills vine weevil larvae down to temperatures as low as 5.c. Apply Vine weevil killer nematodes once in the spring [March-May] and once in the late summer/autumn [August-November]. By applying twice a year the nematodes can break the vine weevil life cycle. Any vine weevil adults that invade gardens in the summer and lay eggs are killed by the autumn application against their larvae. Any larvae that are missed in the autumn application are killed by the spring application, which targets then overwintering vine weevil larvae. The nematodes are watered into the soil or compost. After this the nematodes seek out and kill the vine weevil larvae. They use the body of the vine weevil larva to reproduce in. The infected larva or grub then explodes underground and releases more nematodes into the surrounding area to look for more vine weevil larvae. The soil or compost should be watered after application and kept moist for up to 14 days.

Appearance and Lifecycle
Vine weevils are beetles that attack a wide range of plants. There are now several species in the UK with the most common being the Black Vine weevil. The adults are about 9-14mm long, pear shaped and dull black in colour with slight yellow markings. All the adults are female and lay hundreds of eggs from April-September. These develop into 'c' shaped and legless larvae with a small brown head. The larvae stop feeding as temperatures drop. They resume feeding in the spring and stop feeding in May before pupating and turning into vine weevil beetles. The larvae can be present feeding all year round if present indoors. The eggs are brown in colour, which makes them difficult to see in compost or soil.

Symptoms and Damage
The damage from the adult vine weevil beetles appears as notches on the leaves, which are often half moon shaped. The adults are active at night time and are highly mobile. The damage the adults cause is disfiguring especially to ornamental plants. However the damage caused by vine weevil larvae is much more serious. Vine weevil larvae feed on plant roots and also bore into tubers and stem bases. One of the first signs of this activity can be when plants wilt. Once this happens it is almost certainly too late for the plant. Container or pot grown plants are especially vulnerable to attack from vine weevil larvae. Vine weevil attack many types of plants including; strawberries, bedding plants, shrubs and trees.

Natural Choice Treatments
There are currently no treatments available to gardeners for treating adult vine weevil apart from the Natural Choice Vine Weevil Killer.