Weevil Control on Vegetables, Home Guides, SF Gate
Weevil Control on Vegetables
- 1 Weevil Control on Vegetables
- 2 Weevil Description
- 3 Manual Control
- 4 Barrier Control
- 5 Organic and Non-Organic Insecticides
- 6 50 ways to kill a vine weevil? Help!
- 7 50 ways to kill a vine weevil? Help!
- 8 Replies
- 9 10 Best Steps to Keep Weevils Out of Your Food
- 10 10 Steps to Controlling Food-Infesting Weevils
- 11 Professional or Chemical Treatment
- 12 Strawberry plants in pots & containers
- 12.1 Growing strawberries in containers
- 12.2 Growbags
- 12.3 Hanging Baskets
- 12.4 In the long term
- 12.5 Varieties to use
- 12.6 Getting early fruits – extending the strawberry season
- 12.7 In the gently heated greenhouse
- 12.8 Cloching
- 12.9 PESTS AND DISEASES
- 12.10 Aphids [greenfly]
- 12.11 Botrytis – grey mould
- 12.12 Mildew
- 12.13 Leaf spots and blotches
- 12.14 Slugs
- 12.15 Red Core
- 12.16 Viruses
- 12.17 Verticillium wilt
- 12.18 Vine Weevil
- 13 How to Get Rid of Weevils
- 14 Weevil Identification
- 15 Best Methods of Weevil Control
- 16 Control Weevils with Pyrethrins
- 17 Best Natural Weevil Control Methods
Learn how to keep weevils off your vegetables.
A successful vegetable garden means properly dealing with the presence of pest insects, such as the vegetable weevil (Listroderes costirostris obliquus). Weevil larvae and weevil adults eat the foliage as well as the roots and buds of your prized vegetable crops, including cabbages, carrots, beets, onions, radishes, potatoes, tomatoes and spinach. The neighbors might think you’re nuts, but grab your flashlight and head out to the garden after the sun goes down to combat weevils — these pest insects are most active and easiest to spot in the evening hours.
The vegetable weevil is a type of snout beetle that is about 1/3 inch long. Weevils are gray-brown in color and feature a light «V» shape on their wings. Despite having wings, they do not fly and can live for up to two years. The larvae of these insects are leg-free and green and reach the same lengths as adult vegetable weevils. Weevil eggs are a whitish color that turns black before the insects hatch.
Inspect vegetable crops in the evening and remove weevils by hand. Wear gloves when removing weevils and place the bugs in a jar of soapy water or other control method that will kill these insects. If you discover one or more rows of vegetable crops are infested with weevils, remove and destroy these crops to avoid further infestation. It is also beneficial to cultivate the soil to kill eggs and larvae, and rotate your crops whenever you can to control weevil infestations. Mix plants repulsive to weevils with your vegetable crops, such as bay leaf or allium, though the latter cannot be planted alongside peas or beans. Keep your gardens free of debris and weeds, as they provide rest areas for weevils and other pest insects.
Use assorted barrier control methods to keep weevils from snacking on your vegetables, such as sticky barriers and protective row covers. Find both at your local nursery. Sticky barrier products prevent weevils from moving from one host plant to the next, and instead keep them in one area of the garden only. Protective row covers are made out of assorted synthetic materials, including woven plastic and vented polyethylene. Use them when vegetable plants are in seedling stages and keep them on plants until plants are large enough to sustain damage. Cloth barriers are often hung over domelike frames and prevent weevils and other pest insects from laying their eggs on new plants.
Organic and Non-Organic Insecticides
Organic insecticide solutions for vegetable weevil control include sprinkling diatomaceous earth, which is composed of the skeletal remains of diatoms, an ancient form of algae. The microscopic sharp edges of these diatoms are not harmful to mammals, but will cut into insect bodies or destroy them from the inside out if ingested. Though diatomaceous earth is not harmful to humans, be careful not to inhale it. Non-organic insecticide options that can provide some management of weevils include insecticides pyrethrin and azadirachtin. Use a garden sprayer and follow the manufacturer label instructions for best results. Wear protective clothing and gloves when handling these insecticides, as both are quite toxic.
50 ways to kill a vine weevil? Help!
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50 ways to kill a vine weevil? Help!
Hot on the tail of the slugs thread (do slugs have tails or just long necks?), I have been infested by vine weevils for the past 2 years. Last year was the worst — all over the garden and we found them in the kitchen (crawled into a loaf of bread), the bathroom and even once in my bed! I HATE THEM! But even worse than the beetle thing itself is the little c shaped maggots in the pots.
My garden is mostly a back-yard pot garden and although I have treated the plants twice this year already with vine weevil killing juice, it costs a fortune from the garden centre (like £9 a tub and it takes 2 or 3 to do the whole yard). I have still killed around 4 vine weevils a week (they make a really horrible crack when you stamp on them) so I hate to think how many little wriggling babies they have left in my pots.
I can’t seem to find treated compost in any of our garden centres (repotting would be a nightmare!), nemotodes are difficult as we live in a funny climate here — can go from hot to cold very quickly and rain lots so timing the nemotodes is difficult.
Any ideas? These things really are the bane of my life!
Two ways without nematodes is a) make pitfall traps from plastic cups with paper cones in and b) put folded sacking around or near the base of plants for them to use to hide up during the day — then of course, you squish ’em.
A google on «Vine weevil»+control brought up all sorts of sites that you’d have to evaluate for yourself but to start you off take a look at This One.
Thanks to everyone for their useful suggestions on my previous «Squirrels vs bulbs» thread and great to see that we now have a Gardening Board — cheers MSE.
We moved into our first home with a garden in September and I couldn’t wait to get started. On day one however I discovered that we have a very large and very healthy colony of the dreaded vine weevil and my enthusiasm has just vanished. (Hence planting of bulbs in pots).
The little swine have eaten bergina, rosemary and hellobores left by the previous owner in various beds (I couldn’t believe the damage on the rosemary).
The garden is only small and has one panel fence covered completely by ivy and a back wall also completely covered by ivy which provide ideal conditions for these voarcious thugs — which is why they don’t seem to eat ivy I guess.
Getting rid of the ivy isn’t an option, so does anyone know of some treatment that reliably gets rid of this scourge or even controls it at a reasonable level. I know you can get biological controls, but are they really effective outside. I also read of treatments for containers, but these aren’t supposed to be used on open ground. I’d really like to be as green as possible, but there’s little point in me being green if the garden can’t be!
Sorry to go on, but the blighters are really bad and I’ve waited so long for my own patch I’m actually quite dowm about it and all for giving up — which is stupid, I know.
10 Best Steps to Keep Weevils Out of Your Food
Do you have pests in your pantry? Strange bugs in your food? Weird crawling insects in the kitchen?
If you have seen a rather strange, long-nosed bug weevils crawling or flying in or around your pantry or cabinets where you store food, you most likely have an infestation of weevils in a food package. These bugs, most identifiable by their long snouts, do not harm people, pets, or home furnishings, but they do damage grains and seeds, and large populations can destroy food.
Weevils can be of two types: weevils that infest food and those that are destructive to outdoor plants. Either of them can be an annoyance in the home, but this article focuses on weevils in food.
10 Steps to Controlling Food-Infesting Weevils
- Inspect all stored foods to find all foods upon which the weevils are feeding or infesting.
- Weevils may be seen outside the area of foods they have infested, so it is important to check all foods in the home to ensure all weevils are found and eliminated.
- Closely examine the foods these insects prefer to eat: whole grains, seeds, rice, nuts, dried beans, cereals, corn, and other such foods.
- Discard or treat (see step 6) any foods in which weevils are found.
- Empty all foods (infested or not) from the pantry, or area that is infested.
- If you find a food that is infested, or you suspect it may be, and you want to try to kill the weevils instead of discarding the food, you need to first determine if it can withstand heat or cold. If so, you can kill the weevils, their eggs, pupae, and larvae by heating the product to 140 F for 15 minutes or freezing at 0 F for three days.
- Once all food is removed, vacuum the shelves (both top and bottom), and floor, using crevice and/or brush attachments and paying close attention to edges of shelves, floor/wall junctures, and corners to ensure all insects are captured. Empty or discard vacuum bag outdoors.
- Vacuum and/or clean all areas around the infested area, e.g., sweep and clean kitchen floors; remove items from countertops and clean thoroughly; pull out the stove, refrigerator, and other appliances and sweep and clean beneath.
- Wipe shelves clean, getting into cracks, crevices, and corners.
- For at least the next month, be sure that all foods are in tightly sealed containers or stored in the refrigerator or freezer to ensure that the infestation is eliminated.
Professional or Chemical Treatment
Professional and chemical treatments are not needed or recommended for weevil control. This is because insecticides should not be used in or around foods and even spraying emptied areas won’t help if they are not cleaned out as explained in the steps of this article.
If you do decide to use an insecticide, use only those that are labeled for crack and crevice treatment in food areas and use only in those cracks and crevices. Insecticides can never be applied to foods or surfaces, utensils or other items that can or will contact foods. As with any pesticide, thoroughly read and carefully follow all label directions.
Strawberry plants in pots & containers
Growing strawberries in containers
No fruit plant could justifiably claim to be more suited to container cultivation than the strawberry and very good results can be achieved with quite a modest outlay. This method of cultivation is an ideal alternative where garden space is at a premium. Perhaps you wish to keep your strawberries close at hand, on the patio or terrace, or even by the door. Practically any container can be utlized provided it has a minimum depth of around 12”. The quantity of plants you can incorporate will be determined on the soil capacity of the container; the normal rules of plant spacing do not apply here since you will not be keeping them in the pots long-term. As a rule of thumb for strawberry plants a container size of, try to stick to 1 plant for about 1.5 litres of compost.
Always use a good quality proprietary all purpose compost. Do not use garden soil as it compacts too readily when used in containers. You can also make your own by mixing equal parts garden compost, plain peat and sharp sand with added fertilizer of your choice.
Are often used for growing strawberries; it’s not my preferred method but it is convenient as the growbags come ready-made so to speak and all you have to do is slit a hole and pop them in. But you must be very vigilant in watering as there isn’t a great depth of compost for the plants to use. 3 plants will fit in a standard growbag. You can also use proprietary bags of compost – 60 and 80 litre are ideal – and simply cut holes in the bag yourself; because the volume of compost is greater than with growbags I often feel these are a better option although a little more expensive.
Are a wonderful and novel way of growing strawberries! They make a very attractive feature and of course take up no garden space at all. A standard 12” hanging basket can incorporate three or 4 plants. Additional advantages are that the fruits hang temptingly down over the sides of the basket – a most attractive sight – and they keep clean with no soil-splashes, bacterial and fungal diseases tend to be kept at bay because the air circulation is better, and the plants and fruits tend to be troubled less by slugs. Such advantages do come at a price, however. You must be very vigilant in your watering, every day at least, or even twice a day, once in the morning and once in the evening, for really good results. Of course aerial containers such as this are very susceptible to drying out and the strawberries must have adequate moisture to develop the best, most plump berries, as well as to maintain the health of the plant.
In the long term
Whatever containers you plan to use, aim to keep them for one season, or two at the most. After that plant them into the garden if you can, or discard them and start again. Very regular watering is essential throughout the growing season. And regular feeding too is very important. Seaweed Maxicrop applied fortnightly as a foliar feed is a very good method of ensuring your container grown strawberries receive a regular dose of sustenance. You can also use Osmocote tablets which are very convenient to apply and one application will feed the plants for a whole growing season! In the case of containerised strawberries growmore and bonemeal are not so suitable.
Varieties to use
Any strawberry varieties will grow well in containers but to make recommendations I would probably discard those taller and more rangy growers as they will become very untidy in containers and the rich compost can actually encourage even taller growth! For this reason I would suggest varieties such as Cambridge Vigour, Emily, Honeyoye, Pantagruella, Brenda, Florence and the perpetual varieties such as Flamenco, Ostara and Aromel. Elvira is also often recommended for container growing. If you plan on doing several containers then aim for a good mix to cover the season but if you’re intentions are more modest then perhaps stick to a long-fruiting perpetual type, or the day-neutral ‘Seascape’ which will bear berries in flushes right through the season.
Getting early fruits – extending the strawberry season
With a little for-thought, it is quite easy to get valuable extra-early fruits that can extend your picking season by 3-6 weeks or more. Any and all varieties can be encouraged to fruit ahead of their natural season but the most value lies with the earlies. Cambridge Vigour remains at the forefront of most forcing programmes, Emily, Honeyoye and Elvira as well as Rosie are also very suitable regardless of the method you use.
In the gently heated greenhouse
By far the earliest crops will be gained by potting up established plants from a strawberry bed in February. New just-bought plants can also be used as long as they are of good quality and you will get some fruits but established plants will yield better. Pot the plants individually in 10” pots, using a good proprietary general purpose compost, watering well of course and place them in a greenhouse with a heater thermostatically controlled to maintain a minimum 50 degrees overnight and a gently agreeable 60 degrees during the daytime.
The plants will start to make active new growth almost immediately and after 2 weeks or so start providing additional foliar feed. Flowers will appear within 3-4 weeks and because of the closed environment you will need to pollinate them by hand using a soft haired brush or even a feather, because there will not be any flying insects inside the greenhouse to pollinate the flowers naturally.
The first fruits should be ripe by mid April – a full 6 weeks ahead of the outdoor season for strawberries.
Is a good way of encouraging early ripening from established outdoor plants. You can either place the cloches over the plants as growth begins in early spring, or you can wait until flowering has just finished. If you decide to start early then you must remove the cloches at flowering time, and only during the day, to allow the flowers to be pollinated by insects. Then put them back over-night. Be prepared to give some extra water during this period because of course the plants will not receive natural rainfall. When harvesting has completed remove the cloches and give the plants a good haircut to tidy them up and remove any unwanted pests and diseased.
PESTS AND DISEASES
However hard you try to keep your plants healthy, a few gremlins are bound to appear from time to time. Prompt action, or better still, prevention where possible – is always the ideal.
Are more of a problem in the Spring when the fresh new foliage is soft and just emerging. They cause the leaves to twist and curl and these leaves may also take on a yellowish tinge. If infestations are left unchecked they can weaken the plants and aphids also spread other diseases. They are relatively easy to deal with; cut away and burn infected leaves and then treat the plants with a systemic insecticide such as Provado. If you don’t want to use an insecticide and the infestation is light then a spray with soapy water can often do the trick. Biological controls are also available but these can take time to establish and have any effect.
Botrytis – grey mould
Occurs on the berries themselves; keeping the berries on a clean surface and away from wet soil lessens the chances of this problem occurring. It is more prevalent during wet summers or where overhead watering has been practiced. A good fungicidal spray can prevent the problem in subsequent years, applied as the flowers set.
Once the problem has already occurred the only cause of action is to remove infected fruits to limit the spread.
Is easily identifiable by the silvery powder that occurs on newer leaf growths. Some varieties are more prone than others and plants grown under cover will be more susceptible; spray at the first sign with Systhane fungicide.
Leaf spots and blotches
Various fungi can infect and produce circular reddish or purple spots on the leaves, often fairly late in the season. You can spray with a fungicide but these symptoms aren’t usually too important.
Are as partial to temptingly ripe strawberries as we are! There’s nothing more annoying than selecting a seemingly large and ‘perfect’ berry only to find than underneath it has a large hole! Good standards of husbandry and cleanliness will reduce the chances of slug infestations because the less shelter and decaying plant material there is in which to hide then the less happy the slugs will be. This applies to the surrounding area as well as the actual strawberry bed itself. Various remedies are on the market to deal with these slimy pests [which must alas also include the more endearing but none the less damaging snail] such as traps, deterrents and poisons.
There is no cure for red core [also known as Red Stele] and where this disease has been identified in the past makes the soil unsuitable for growing strawberries so choose an entirely different area. The variety Red Gauntlet and also Allstar, are known to be red core resistant.
Red Core manifests itself as a general weakness in the plant with wilting yellowing leaves, stunted growth and fruits which are bitter and hard. Leaf stems and roots reveal a red inner core. The fungus is spread by water travelling through the soil. Soils which have better drainage are therefore less likely to get this disease.
Are more of a symptom with older plants which is why it is important to replace your strawberries every 3-5 years. The symptoms are dwarf, stunted and yellowing plants which do not grow and remain largely unproductive. There is no ‘cure’ for virus except to dig up and burn infected plants, replanting with healthy new stock in a separate area. If you must use the same ground then either dig out the soil and replace with fresh topsoil, or treat it with jeyes fluid 6 months before re-planting.
Is a serious disease, the symptoms if which are yellowing basal leaves and in turn the whole plant wilts and collapses. A fungicidal drench to the crown and roots of unaffected plants may help but this is a difficult disease to treat and often the only answer is to destroy the plants and start again elsewhere.
The symptoms of vine weevil are similar to verticillium wilt in that hitherto the plants appear healthy but suddenly wilt and no amount of watering revives them; however Vine weevil is easy to distinguish because a gentle tug on the affected plant and it will simply come away from the soil with most of it’s roots eaten away beneath. Fat white grubs can be seen in and around the base where the roots were. The adult vine weevil is quite a cute looking, slow moving beetle-like insect but is anything but cute! Nematodes are available to control vine weevil infestations and you can also buy compost that has been ready-treated against this pest. Vine weevils are especially likely to be a problem with plants that have been grown in pots and containers, and they are also attack many other types of plant, such as Geums, Heuchera and some shrubs.
So there we have it – a guide to strawberry cultivation based on 30 years of trial, error and experience! I hope you have found it of use and hopefully an inspiration too. I am always happy to advise on any aspects of strawberry growing, if you have any questions e-mail me.
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How to Get Rid of Weevils
Updated — October 5, 2019 / Eric Ronning
I am pleased and honored to be the one to tell you that yes, you have eaten weevils. I know it’s a disgusting thought (or an invigorating one, no judgement), but there’s really nothing to be done about it. Most people are never even aware that it has happened. It might have simply been their eggs. It could, however, have been little bits of exoskeleton, maybe a leg or two, or possibly even the entire nasty weevil . . . or at least its larvae. With something as common as weevils, it’s pretty much unavoidable. They can be found in nearly any prepackaged food you buy that contains any sort of grain. I’m talkin’ cookies, crackers, biscuits, cake mixes, pastas, breakfast cereals, anything. This is due to the fact that weevils lay their eggs in, you guessed it, grains.
The two most common types of pantry weevils are the granary weevil (Sitophilus granarius) and the rice weevil (Sitophilus oryzae). They are often referred to as snout weevils. These little pantry pests are actually beetles; very small beetles that rarely get any larger than ¼ of an inch. Female weevils use their little snouts to drill holes in the casings of grains, such as wheat, oats, rye, rice, corn, barley, and various seeds and beans. Once the hole is drilled, she deposits an egg and seals the hole back up with a gelatinous glue-like substance that she creates all by her little self. The egg hatches after a few days, and the larvae uses its surroundings as a lunch box for about the next month. For this reason, it can be difficult to detect an infestation. Not only is it slow to start but the larvae are in hiding. Once grain weevils (a.k.a. flour weevils) or rice weevils present themselves, you’ve got a problem. A single female can lay up to 400 eggs, which means up to 400 more hungry bugs lookin’ for a snack. If you’ve experienced something like this, you’ll need to know how to control and get rid of weevils.
- 1/8- to 3/16-inch long
- Dull reddish brownRound pits on thorax
- Four light spots on carapace
- Able to fly
- Found more commonly in warmer states
- 1/8- to 3/16-inch long
- Shiny reddish brown
- Elongated pits on thorax
- Can’t fly
- Found more commonly in cooler states
Best Methods of Weevil Control
Remove contaminated food products.
Sounds like a no-brainer, but this might be the single most important step in getting rid of weevils. Look through your ENTIRE pantry and every single cupboard for any food products that might be contaminated. If you find something that you aren’t sure of, pitch it. There’s no point in risking reinfestation. It could very well cost you more money in the long run. Once you have it all gathered up, take it outside to the trash immediately and move the can as far away from your house as possible.
Pull a Cinderella.
Conduct the most thorough cleaning of your pantry and cupboards that you have ever done. Start by taking absolutely everything off the shelves and vacuuming them. Make sure to get all the cracks where flour or other food bits might be hiding. If you have contact paper lining the shelves, remove it (you can put new stuff on later). Use a rag and some hot sudsy water to do the rest of the cleaning.
Kill weevils with cold.
To avoid future problems with weevils, it is advisable to freeze your food. You can do this to flour, oats, cookies, corn meal, grits, whatever. If you have the space in your freezer, you should just keep the stuff in there full time. If you have a small freezer and can’t afford the space, set the freezer as cold as it gets and leave the food in there for at least four days. That will kill any eggs, larvae, or weevils. Also, that’s an added 4 days of shelf life!
Kill weevils with heat.
If you don’t feel like freezing everything, a little heat exposure will accomplish the same thing. Spread your food or seeds thinly on a baking sheet, preheat the oven to 120°F, and leave it in there for 1 hour. If you’re impatient, you can do 130°F for ½ hour. If you want to use the microwave, spread the stuff on a glass dish or plate, and run it for 5 minutes. Keep in mind that if you are heating seeds for gardening, the heat may destroy the seed’s chances for germination. Also, don’t heat fine-grained things, like flour, in case of combustion.
Further weevil prevention.
Start by cleaning the cupboards and pantry regularly. If you spill something, clean it up immediately and thoroughly. In the pantry and cupboards, you may want to consider sealing any shelving cracks with caulk to keep food from getting trapped down there in the future. Buy your goods in smaller amounts that you can use quickly. Rotate your stock and don’t mix new food with old. Finally, store all of your perishables in tight-lidded glass, tin, steel, or plastic containers. If you have limited cupboard space, Rubbermaid modular containers (sold at Amazon) may be a good plan.
Control Weevils with Pyrethrins
With as common a pantry pest as weevils are, you would think that there would be quite a number of pesticides that target them directly. Unfortunately, this is far from the case. The reason is simple: weevils live and breed in your food. Since you would like to eat that food, contaminating it with insecticides probably isn’t the best idea. For this reason, you should probably just stick with pyrethrins. There are quite a few different pyrethrin sprays and aerosols available that are sold to be used indoors and in food handling areas. You should still avoid spraying the food directly. Once your pantry and cupboards are completely empty, spray them down. I would recommend you leave the cupboards empty and open for at least a few hours before filling them back up. Look for products such as CB-80 Extra, Riptide Waterbased Pyrethrin ULV, and Konk Too.
Best Natural Weevil Control Methods
Bay leaves are a natural weevil deterrent. After freezing or heating your grains, drop a bay leaf or two into the storage container on top of the food product you want to be protected. You may also wish to randomly scatter a few leaves around the cupboard or pantry. Amazon sells a bundle of ’em here.
Cloves are another natural deterrent for weevils. Treat your grains with cloves the same way you would with bay leaves. After treating your food with hot or cold, drop a clove on top of it before storing. Scatter a couple around the cupboards and pantry too. Hell, go crazy and try a couple of each.
Sounds odd, I know, but I read this suggestion in a number of places. Take a plain old matchbook, open it up, and set it in with your grains or pastas. Apparently the sulfur smell from the matches acts as a weevil deterrent.