How to use predatory insects for your garden (2024)

How to use predatory insects for your garden (2024)

Lovingly-tended healthy plants provide perfect conditions for pests to invade and establish. In natural ecosystems, pest numbers are kept down by their natural predators. Using beneficial predators in your garden controls and rebalances insect populations naturally. 
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Using natural predators to protect your garden

Lovingly-tended healthy plants provide perfect conditions for pests to invade and establish. In natural ecosystems, pest numbers are kept down by their natural predators. Using beneficial predators in your garden controls and rebalances insect populations naturally. 

We supply native British species of predatory and parasitic beneficial insects for use around your home and garden to control pest insects. These beneficial predators come ready for immediate use and are released onto pest infested plants.  

Beneficials, predatory and parasitic insects and mites, are the most well known form of biological control. Using beneficial insects in a growing system provides long term pest control helping fight nature with nature. Relied upon by the UK horticultural industry for decades, using beneficials in your garden takes these tried and tested natural predators and allows them to be used in garden greenhouses, conservatories and homes. Beneficial insects have the advantage of attacking pest insects, they are harmless to people, plants, pollinating bees and pets. 

Because our beneficial insects are native to the UK, they are often already found within a garden. The aim of introducing more is to temporarily boost their population to allow them to get on top of the pests which are causing a problem. Pest insects and mites often reproduce faster than the natural predators feeding on them, this means the pest insects can increase to a level where it starts to damage plants before the natural predator population can catch up. Adding extra help by releasing additional beneficial insects helps the predators get on top of, and control, the pest faster.    

 

Using natural predators and parasites is the ultimate organic pest control.  Predatory insects and mites are natures way of controlling unwanted pest insects, MightyBugs help nature on its way. A range of predatory insect and mites can be used to control pests. Some are very specific in the pests they will control, others are more generalist predators and will consume anything which doesn’t run away. Predators and parasites are mobile hunters and so ideally used in situations such as greenhouses, cold frames, conservatories or indoor locations within which they are contained. There are some however which are less mobile, such as ladybird larvae and so can be used in outdoor situations and will stay close to where they are released.    

If you are planning to release predators into your plants it is important to remember that chemical insecticide sprays will also affect these beneficial insects. If you are planning to use a chemical spray before releasing beneficial insects it is important to consult the product page and allow sufficient time between the chemical treatment and the insect release. 

The best practice for controlling pests and growing healthy plants is regular checking of your plants to ensure they are healthy and not infested with any unwanted visitors. When pest insects are found, quick action is needed to prevent them increasing in numbers rapidly and becoming a big problem which may be too much for your plants to recover from. 

Advantages of using biological control in your garden: 

Biological controls can have advantages over pesticides which hare usually broad spectrum and can kill a wide range of invertebrates: 

  • Biological controls cause no damage to plants and do not leave residues. 
  • Once established, natural enemies can breed and increase in numbers until the pest has been reduced to an acceptable level. Once the pest population has been reduced the beneficial population will also reduce as there are no longer pests to either eat or lay eggs within. 
  •  Biological controls are more targeted in the insects that they will kill in your garden, targeting those pest insects rather than an alternative of chemical pesticide which will harm any insect they come into contact with.  
  • There is no need to have time between applying biologicals and eating food from your garden unlike chemical pesticides which have a harvest interval. 
  • Using biologicals is highly targeted affecting only pest insects whereas chemical pesticides will reduce the overall insect population (both good and bad) with the pest population often able to more quickly re-establish itself and recover. 

Why can't I wait for the natural populations of predators to control the pest insect? 

In natural situations, predatory and parasitoid biological control rarely give instant reduction in pest insect populations. They need time to locate the prey and then to reproduce to a population level high enough to predate all of the pest. Pest insects often have faster population development rates, introducing natural predators is designed to overcome this initial delay. Releasing natural predators and parasitoids boosts their population allowing them to get on top of the pest insect population faster.  

 Ladybird eating aphid

When is best to introduce beneficial insects and predatory mites? 

When to use the beneficials will depend on the conditions they are being used in. Unheated greenhouses and outdoors should use from April to September. Heated greenhouses and indoor plants can use then year-round. Greenhouse predators and parasitoids, just like the pests they control, require warm conditions. They generally require daytime temperatures of 21’C, greenhouse and outdoor biological controls will often die out during the winter due to cold weather and a lack of prey predators need to feed or reproduce within, reintroductions will be required. 

 

Can I use chemical insecticides at the same time as beneficial insects?  

Chemical pesticide treatments should be avoided for 6 weeks before the release of biological controls. The chemical insecticide will harm the beneficial insects as well as the pest species. In addition, the pest insect population is likely to recover faster and return sooner after the chemical insecticide application than any surviving beneficial predators.  

 

Will releasing beneficial insects interfere with the natural ecosystem? 

 All of the predatory insect and mite species used in our MightyBug products are native to the UK, this means that they are found here naturally. Releasing beneficial insects temporarily boost their population allowing them to get on top of the often faster-growing pest insect population. Once the pest population is controlled the population of beneficial insects will decrease as there is no more food for them. The population of beneficial insects will decrease down to the natural level it was before you released them.  

There are also other predatory species of beneficial insects which can be found naturally in your garden which are not commercially available such as rove beetle and hoverfly as well as larger garden friends such as hedgehogs, frogs, toads and birds. Using natural beneficial insects to control pest insect and mite populations will also help protect and work alongside these other gardening friends. 

 

What is biological control? 

Biological control (or biocontrol) is the use of natural solutions to manage a pest or disease. There are four categories;  

  • Micro-organisms. Small organisms you cant see with your eyes, for example bacteria, fungi and viruses 
  • Macro-organisms. Larger organisms you can see with your eyes, for example insects, mites and nematodes 
  • Semio-chemicals. Manufactured versions of natural scents produced by insects, for example pheromones used in codling moth (PRODUCT PAGE LINNK) and plum  moth (PRODUCT PAGE LINK) traps. 
  • Natural substance. Manufactured versions of natural compounds.   

Biological control, especially the use of predatory insects has been relied upon as the backbone of British tomato, cucumber, pepper, herb and soft fruit production for many years is now available for use in your garden. 

 

What types of biological control can I use in my garden? 

For gardeners in the UK there are a range of biological control products available including predatory insects, parasitoids, predatory mites and insect killing nematodes. The best product to use will depend on the pest you are trying to control. Biological control products tend to be more specific in what they work against than a chemical insecticide.  

 

Where can I use beneficial insects? 

Beneficial insects can be used in most growing systems including greenhouses, cold frames, polytunnels and other contained settings. Species (such as Trichogramma evanescens) or life-stages (such as ladybird larvae) which do not travel far from their release point can also be good options for control of pest insects in outdoor settings.  

   

Why are beneficial insects only available to buy online? 

Our MightyBug predators and parasitoids are sent directly to you, being living creatures they need our special storage conditions and can not sit on a shop shelf, which is why beneficial insects are not available to buy in garden centre shops. 

 

Best practice for using beneficial insects 

  1. Diagnose problem. Before you begin you need to know exactly what kind of insect or mite pest is damaging your garden so you can identify which predator you require. Ensure that you have not used a chemical insecticide recently that could harm the beneficial insects once they are released. 
  2. Order predator insect. Read the instructions on the product page for how best to use the product. Plan when you expect the beneficials to be delivered, remember they are living animals and need to be used immediately after you have them delivered, ideally the same day. 
  3. Release the beneficials. Your delivery will come with detailed instructions of how to release the beneficials. You can also watch our “how to” videos online. Pay attention to instructions about time of day of release, whether to dispense onto the soil around a plant base or into a dispensing box. For best results release them either early in the morning or in the early evening out of direct sunlight. If the beneficials are supplied in loose material this should be applied in small batches over the area which requires protection. 
  4. Protect your investment. After they have been released look after the beneficials. Keep the plants healthy and well watered, do not use any chemical insecticide treatments which could harm the beneficials. 
  5. Patience. Give the beneficials time to work. Unlike a chemical insecticide, beneficial insects do not give you an instant kill of the pest insect population, over the coming days and weeks the beneficials will gradually consume the pest insects so bringing their population down.    

 

Which species of garden pest can be controlled with biological control? 

Lots of common garden pests can be controlled with biological control: 

 

Aphid

Aphid is a common name used to group a number of different insect species, and they are commonly referred to as greenfly and blackfly. There are a wide range of different aphid species in the UK, although those species which plague gardeners are more limited and are often related to the plant type the aphid are living on. To find out more information about aphids and how to control them, click here https://andermattgarden.co.uk/collections/garden/aphid 

 

Caterpillars 

There are a number of different caterpillars (Lepidoptera) which can infest plants in a garden. It will often depend on the plants being grown. Common pest moths and butterflies include cabbage whites (Pieris rapae and Pieris brassicae) most often found on brassicas and carnation tortrix (Cacoecimorpha pronubana), light brown apple moth (Epiphyas postvittana), Silver Y (Autographa gamma) and cabbage moth (Mamestra brassicae). Since its introduction to the UK, box moth (Cydalima perspectalis) is a significant pest of decorative box bushes. 

 

Whitefly

Similar to aphids, whitefly are sap sicking insects. Adults are easily identified by their white wings. They can often be found on the underside of leaves. 

  

Sciarid fly 

Whilst the adult flies can be a nuisance, it is the fly larvae which cause the damage. Living in the moist soil needed to keep plants healthy they can feed on small roots and seedlings.