Watered into pots or open ground with a watering can or hose, and which kill the vine weevil grubs, we supply packs of microscopic worms.
Sold in 2 sizes, all our prices include P&P. Due to production issues this product will not be despatched until early December.
Vine Weevils are a real double whammy for gardeners...the grubs or larvae eat the roots, and the adult eats the leaves! The damage is distinct from slug and snail damage as they bite the edge of the leaves rather than making holes in the middle.
Adult Vine Weevils are black beetles about 8mm long with the front part narrower than the back, so that they look as if they have a long nose, or snout. It is important to look for this feature, because otherwise they can be confused with ground beetles, which are a gardener's friend. If you see bitten edges around the leaves of your plants, then suspect vine weevil. To see them in numbers you will need to take a torch and go out at night-time into the garden and search among the leaves.
The adult feeds at night on leaves, making unsightly notches around the edges, hiding during the day. During the period from June to August you may still be plagued by the adult beetles. We sell a trap for the adults, more details on this here.
Some gardeners go out at night, and lay out a sheet underneath their most vulnerable shrubs or plants. Then they shake the shrub to tip the beetles onto the sheet, gather up the sheet, and dispose of the beetles. One tip is to sprinkle a thick layer of grit around plants at risk to deter egg-laying adults.
Vine Weevil Grubs
Eggs are laid near the plant stems in the summer and they hatch into white, horseshoe shaped grubs which stay in the ground during summer and autumn and winter and only emerge into adults the following year - typically early June. Vine Weevil larvae are ugly-looking grubs which feast on plant roots, often completely severing them from the upper stems. You can recognise them by their soft creamy-white body, up to 1.5 cm (half inch) long and their brown heads. They often lie in a sort of "C" shape.
We supply packs of microscopic worms (eelworms or nematodes) which are watered into pots or open ground with a watering can or hose, and which kill the vine weevil grubs. The parasitic nematodes enter the grub, poisoning it and then feeding off it to increase their numbers.
Life Cycle: Adults typically emerge in June, start laying eggs in July through into the Autumn, but are typically killed by winter frosts. By that time the eggs have produced larvae (August) and these larvae feast on roots below ground until winter, when they dig in deep below the frosty soil, and hibernate until spring. As soon as the soil gets warmer (March-May), they start feeding again, and then pupate in May/June, to release a new set of egg-laying adults.
When to treat: There are two opportunities to attack vine weevil grubs – one from March to June when they have emerged from their winter semi-hibernation and one at the end of the season when they have just hatched out (August to November). If you see grubs outside these months the treatment is still effective, but remember the soil needs to be warm and wet – don’t treat in the depths of winter if the soil is below 5 degrees, and don’t treat at the height of summer when it is too hot and dry for the nematodes to be effective. For the adults use the traps between June and September when they are around in large numbers.
Instructions for use
The nematodes arrive in a sealed pack and should be used fresh. You can keep them in the fridge if you can't use them straight away, but please don't try to store them for long periods.
Apply when the soil temperatures are above 10°C at least 3 hours of the day and keep the soil reasonably damp while the nematodes establish themselves. Vine weevil larvae can be treated in the spring when they first become active, or in the autumn when they hatch. The nematodes do not kill the adults.
The soil should be moist before application and should be irrigated directly afterwards to wash the nematodes into the soil. They do not harm any humans, birds or animals.