To get rid of Weevils in soil you could mainly try chemical as well as non chemical insecticides. However, using chemical insecticides would be poisonous to insects as well as the plants.
As such, you need to apply chemical insecticides at the right time and right amount to get the best results.
To get the best results, it is vital that you know the stage of life cycle of the root weevil and then proceed with application of the chemicals. So lets find about the weevil first.
What is a weevil?
They are the little beetles which are half an inch in length. You could mainly spot them during late spring and in early summer.
Usually, they are dependent on tender growth of rhododendron plants. In addition to that, they would also depend on several other plants such as yews, hemlocks, strawberries, salal, huckleberry etc.
Moreover, you could find plenty of various species of weevils. There could be small beetle type creatures which have a mouth that looks like a snout. But they can not fly.
Following is a list of weevil types which you could commonly spot in both gardens and in homes as well.
Boll weevil – You could spot them on cotton plants
Rice weevil – You could spot them on wheat, oats, rye, corn, or other grains
Black vine weevil – You could spot them on plants, shrubs, trees, or herbs
White pine weevil – You could spot them spruce, pine, lodgepole pines, and black spruce
As you may understand, there could be different species of weevils which could attack different plant verities.
Moreover, they would invade different components of the plant as well. When they become adults, they would chew on the plant stems as well as their leaves.
Consequently, you could spot holes and damage to the plants. However, in that circumstance, they could still manage to survive well and stay healthy.
There would be severe repercussions from weevil larvae, and they would usually live on ground and would be dependent on plant roots.
The larva stage of weevils would start from white eggs, and they could turn black before they hatch. As the time passes, those plants tend to collapse and end up dying.
Weevil life cycle: explained
If you take an adult root weevil for example, it will start laying its eggs in the soil on rhododendron plants during mid-summer as it is their favorite plant.
Over time, those eggs would become larvae from late summer to early fall.
During this time, they would over winter in the top layer of the soil whilst depending on the plant root mass.
Once they grow, they could be more threatening and could be more destructive. They have the potential to depend on the larger roots which are remaining even at the plant base.
Pupation would occur when the soil condition gets heated during springtime and larvae would transform into the adult stage.
The adults could forage on leaves for about 20-45 days before they produce their own eggs.
Generally, an adult is capable of laying around 200 eggs in his lifetime. The lifetime usually would be for about 90-120 days.
Weevil damage and symptoms
You could mainly spot the wilting plan’s parts which are above the soil surface. For example, plant parts such as leaves, young stems, flowers etc. This is usually a repercussion of the chewing done by the larvae on plant roots. They ultimately would be responsible for drought stress in your plants as well.
Deterioration of the plant’s strength and on their growth
stunted root system and irregular shape holes in the leaves. You may usually find them forming first at the leaf margins.
In addition to that, you could spot notching at the leaf edges and defoliation of young trees as well.
Moreover, you could spot irregular shaped rounded holes in flowers.
Apart from the aforesaid, you could spot scars and lesions of fruit skin and even on the fruit tissues as well.
Chewed stems and ringbarking of stems are a couple of more symptoms of weevils.
How to get rid of weevils
Use insecticides to get rid of weevils
This is one great way of avoiding weevils attack. You have the option of choosing either natural pesticides or chemical pesticides to do that.
Best is to apply these pesticides during nighttime as this is their most active period.
On the other hand, if you are using biological insecticides, they do not have any effect on humans.
However you have to still do it with caution. Literally you need to wear gloves and a face mask which could cover your mouth and nose.
Moreover, if you do not have any prior experiences when dealing with the insecticides or with the pesticides, best is to be in touch with a professional so that he could assist you with that.
Diatomaceous Earth to get rid of weevils
Diatomaceous Earth is the most productive way of preventing the weevil attacks and it is a simple process to do as well.
In addition to weevils, you could apply this method to prevent the rest of the pests also from your garden. You simply have to add this to the soil around your plants.
Diatomaceous earth consists of diatoms. Diatoms are usually the fossilized algae which have been broken down into tiny white shards.
Bear in mind that you should avoid inhaling them. It could be very productive in dealing with many crawling insects as well.
Usually, you need to apply diatomaceous earth on the dirt around your plants so that it could act as a protective barrier
You need to keep repeating applying them after watering and rainfalls as well. The reason behind that is, it is not waterproof and will disintegrate when they get wet.
Neem Oil to get rid of weevils
This is yet another biological substance which you could use to repel weevils and other types of pests as well.
Neem oil could halt the insects in feeding as they could interrupt their eating cycle. However, always keep in mind to go through the labeled instructions before you apply them.
Ideally you need to apply them when there is a heated temperature and once the plant resumes flowering.
Best is to start this off with organic neem bliss as this is a complete natural and organic product which does not contain any harmful chemicals as well.
What is more special about this element is that you could apply this for both indoors and for outdoors as well.
Spinosad to get rid of weevils
Spinosad is a biological chemical made from bacteria. It could be effective in using for numerous types of insects such as leaf miners, spider mites and trips in addition to weevils.
Using Spinosad in their insecticide has become quite normal for many of the companies.
You can easily find this chemical as well. You could use this for ornamental and for food crops since this organic chemical is safe for them.
As such, you could apply it for everything you grow. You could get best results if you could make the plant ingest this. alternatively, you could use it via contact and that method would also be quite productive.
Botani-Guard to get rid of weevils
This is a substance which comprises natural fungus which is called Beauveria bassiana strain Gha.
You need to apply this at the very moment you spot the weevil infestation. You could spot the result within 7-10 days of applying the spray.
If it is essential, you would have to apply it once again until you eradicate the weevils. You may use this product not only to treat weevils but also to treat other pests’ types as well.
Manual removal to get rid of weevils
There may be occasions where you have to take these off manually as well.
When you do that make sure that you are wearing a pair of gloves, flashlight, and a container also where you could put the weevils.
What you have to do is simply lay out a sheet box in the evening under your plants. instead of a sheet box, you may even use a bag or an upside-down umbrella or even some newspaper.
When it is nighttime, the weevils would come out and you have to then go there with the flashlight. After that, you should put your hand at the stalk base above the dirt and give it a light shake.
Then, if there are any crawling weevils remaining there, they would fall off into the container which you have located on the ground. When you finished collecting them, you could dispose of them.
In case, the weevils try to hang on to the plants despite the shake you give it, you could use your fingers and slowly take them off away from the plant.
Chemical control to get rid of weevils
If you could spot any severe weevil attack, best is to apply a non-biological synthetic chemical substance.
Whatever you use, you need to ensure that it is a recommended product by the environmental protection agency.
Consider that you are applying them on your vegetable garden, then you need to wash them completely prior to consumption.
Usually, you need to apply the chemical products on the foliage such as leaves, flowers and on stems.
Weevil Traps to get rid of weevils
You could mainly spot them being used for indoor gardening. Having said that, you could also use that for outdoor gardens as well.
You could spot these traps in numerous types as well. They simply give off a pheromone which is equal to the one the weevils produce. As such, weevils tend to think they are secure whereas it actually is not.
Imidacloprid to get rid of weevils
Imidacloprid is basically a chloro nicotinyl systemic insecticide.
It resembles the element called nicotine. This would also be quite beneficial in treating the weevil invasions and rest of other attacks done by thrips and aphids too.
They would mainly attack the nervous system and would be very productive in using for adults and for larvae weevil whilst making them ingest this. Always refer to the instructions and then proceed with applying this.
How to prevent weevil attack?
Clean garden
This is one of the easiest ways of keeping weevils away from your garden. When you keep your garden neat and tidy, it would be very unwelcoming for the weevils.
Further it would beautify the garden too. In addition to that, you could limit the hiding places of the adults’ weevils when you keep your garden clean.
Unless they would attract mulch, compost, weeds or even for the debris on the ground.
Whenever you remove any dead plants or weeds, make sure that you dispose of them far from your garden and do not keep any leftovers from mulch or from compost piles. Do not water them in abundance as well. Unless they could attract water.
Consider that you are collecting rainwater, then you need to do it in a different area. If not, you could use a pan of water which could lure weevils from your plants.
Moreover, if you practice proper crop rotation that would also help to get away from weevils and to avoid reinfesting . Additionally, you could prune the low-lying leaves as well as the stems which could touch the ground.
Barrier to the garden
In addition to keeping your garden clean, you could also consider putting up some barriers. To do that, many people use row covers.
You could use sturdy waterproof fabric and piping for example like PVC or aluminum. Apart from that, you may also use protection like tanglefoot tangle trap sticky coating which would protect your plants.
they would stop these weevils travelling from one plant to the other. However, they would not stop the pets from occupying the garden though.
Moreover, you could wrap your plant stems with clear scotch tape. Alternatively you may also use tanglefoot tangle guard banding material as well. They would secure the plants from insects, rodents and even from sun damage as well.
Safe predator
Weevils do not prefer woodpeckers, birds, frogs’ hedgehogs’ ladybugs and praying mantises.
These are all large predators and allowing them for the gardens and welcoming them is another way of avoiding the weevils occupying your garden. It is safe and natural as well.
To attract them, for example if we take birds, you could establish bird feeders or even birdbaths such as alpine corporation 3-tiered pedestal water fountain and bird birth etc.
it could be beneficial in keeping away the weevils from your garden. you only have to establish them in close proximity with your garden.
Best is to make a bubbler also available in the bath as then the water would have ripples and the weevils would find it even more difficult to settle in.
Moreover, the birds would attract more towards the moving water and if you provide a combination of both birdbath and a bird feeder it would make more and more birds land in your garden.
Related questions
How do I get rid of weevils in my garden?
You could use a granular grub control on the soil or even use an insecticide as explained above.
Are weevils bad for the garden?
They are bad since they are a pest’s type in both indoors and outdoors as well. They could be destructive to the level where they could attack the root system of healthy plants. Further they would end up eating the plant from the roots up.
What do weevils hate?
They usually do not like fragrant leaves plants, for example plants like lavender, lemon balm, Geranium macrorrhizum and mint. In addition to that they would also hate the plants which have furry leaves like stachys byzantina.
How do I permanently get rid of weevils?
Take off mulch and other debris which would not allow the weevils to find hiding places.
You should water them only when it is essential only
Apply the aforesaid chemicals as well as 100 % organic diatomaceous earth which would allow the garden to protect from pests for a longer period.
Conclusion
It is important to understand weevil life cycle to get rid of weevils from your garden soil. That way you can apply correct eradication method in appropriate dosage to the soil.
There are several methods you can use to get rid of weevils and those are explained above with explanation
It is always prevention is better than cure, therefore you should concentrate on prevention methods to completely eradicate weevils from your soil.
Hope this article was useful for you and now you have a better understanding of getting rid of the weevils.
So do not hesitate to practice the aforesaid tips and you will get away from this menace easily as we have covered on how to treat them and even how to prevent them occupying your garden as well.
Read Next: 14 Ways To Treating Spider Mites On Succulents
