How to Control Disease, Weeds and Pests

How to Control Disease, Weeds and Pests

Posted by Alix Francis on 3rd Jul 2018

Sometimes it may seem easier to attempt controlling weeds, pests and diseases with pesticides, but most pesticides contain chemicals which damage our environment and often ourselves when we use them.

Pesticides may not always be a necessary port of call, there are methods you can learn which can prevent diseases from spreading, weeds from growing and pests from ruining your plants and crops.

There are other alternatives to buying pesticides such as being on crop watch and picking the slugs and pests off by hands or you could pull weeds up instead or spraying them with a pesticide.

Beer traps can be used to trap slugs and a simple cover over young plants will protect them from pests.


When left untreated, disease can spread amongst plants and even kill them in some cases. Diseases are usually caused by bacteria, viruses and fungus. It affects all growing stages of plants and all areas of the plants too.

There are three common diseases which are found in the garden;

Powdery Mildew

This is where a grey powder/dust effect is present on leaves. Most commonly found on roses, this disease can affect other plants too. You can prevent powdery mildew with general maintenance which includes regular waters and feeding of the plants but being mindful of not over watering the leaves. Mulch below the plant may also help prevent the disease.

Black Spot

Again, common on roses, the black spot disease causes black spots on leaves and can sometimes be found on other areas of the plants too. Any leaves or stems which have been affected should be removed and destroyed before spreading to other areas and plants. You can also purchase sprays which get rid of black spot too.


Orange globules form under the leaves of plants and potentially other areas too. You may need chemical intervention to get rid of this disease by regularly spraying throughout the growing season with a relevant fungicide.

The common weed groundsel is a common host of rust, removing any groundsel you find around the garden will help prevent the spread of the disease.

It can be quite difficult to prevent the spread of diseases, there are a number of factors which contribute to the spread of diseases and which make some gardens more susceptible than others. This can be anything from location, soil type, climate and so on.

Routine hygiene and house keeping is essential when looking after a garden. Keeping them watered, fed and weed free will help prevent the spread of diseases, and weeds too.


Weeds are annoying because not only do they often look misplaced and on the uglier side, they are a nuisance because they compete with plants for the same nutrients, water, soil and sunlight. Some cause little harm and others can be aggressive weeds which destroy areas of the garden rapidly, typically in spring and summer months.

Garden Weeds

The most common perennial garden weeds are:

  • Dandelions
  • Bindweed
  • Creeping buttercup
  • Nettle
  • Ground elder
  • Horsetail

The most common annual garden weeds are:

  • Groundsel
  • Bittercress

Regular maintenance is the best defence against weeds, removing weeds little and often will stop them growing and spreading throughout your garden.

There are weed killers on the market and home remedies which you can make yourself. It might be worth laying weed control fabric before planting a bed or using mulches and chipped bak on beds around plants.


There are many types of pests which can cause bother to your plants, slugs and snails, insects and animals.

Snails and Slugs

Probably the most common pest in the garden as they tend to munch through your plants and crops. Control methods including removing them from plants when you see them or creating chemical or barrier methods.

Slug pellets can be used but with caution as they are extremely poisonous to wildlife and shouldn’t be used where children play either.


We could go on for quite some time listing the number of insects which are pests to our vegetable garden or fruit crops. Pests such as wasps, caterpillars, aphids, whitefly, vine weevils and so on are to name a few.

Sugary bait traps can be used to lure wasps in and bird attractions can help keep the number of caterpillars down.

Vegetable plants can be protected by planted strong scented flowering plants nearby, marigolds being an extremely effective method.

You can also use chemicals and pesticides however this will kill all insects and not pick out the good from the bad.


There are many animals which could be a pest in your garden from dogs and cats to wild deer and badgers.

You can prevent cats from using the garden as their toilet by sprinkling citrus peel or moth balls around or you can invest in sonic repellent which emits a high pitched sounded that animals find irritating and are meant to leave your garden.

Encourage natural pests

Creating a compost heap and attracting the likes of lady birds will help keep the pest count down as lady birds eat pests.

Lady birds can also be encouraged by having a small patch of nettles or leaving plant debris around for them to hibernate in.

Use Companion Plants to Deter Pests

Help to keep pests away from your flowers & veggies by planting companion plants.

  • Planting marigolds near vegetables – these can help keep greenfly and blackfly away
  • Planting garlic near roses – they can help ward off aphids

Before using pesticides

Think before you use a pesticide, not only do they kill pests, they harm plants, humans and wildlife too. They pollute water and poison aquatic life.

Did you know it costs millions of pounds every year to remove pesticide residue from drinking water?