Controlling garden weeds, pests and plant diseases

Controlling garden weeds, pests and plant diseases

A beautiful garden is easily spoiled by unwanted or unhealthy plants. In this article we’re discussing ways to control garden weeds pests and diseases responsibly and safely.

I think it’s fair to say that anyone with a garden has experienced the challenge of controlling garden pests, plant diseases and of course weeds. The temptation is to nip down to the garden centre and find a chemical to spray on them. But before you do that – please consider the following:

How will garden chemicals affect the environment?
Are sprays dangerous to wildlife?
Could pets be harmed by chemical controls meant for garden pests
Do you know how to apply chemicals safely?
Are you able to dispose of the packaging?
Is there another way to tackle the problem?
Is this job more suited to a trained professional?

Caring for plants will help avoid pests and diseases

Just like us, plants are generally less susceptible to damage from pests and diseases if they are in good health to begin with.

Avoid problems in your garden by feeding plants regularly (with the right feed!), and making sure they have enough water. An automatic irrigation system that can be controlled from a timer or a phone app is an absolute god send for this. Managing trees and hedges will improve air flow around your plants and discourage fungal disease. And a good layer of mulch will help to keep weeds under control.

If you do spot any anything out of the ordinary. Investigate immediately, to find out if you have a problem and what might be causing it. The quicker you take any necessary action, the less likely it is that the invading pest or disease will be able to permanently damage your plants.

Depending on what it is, you may be able to find a cultural cure for the problem. Perhaps water a bit more (or a bit less), feed the plant or pick off any bugs. Sometimes though, the quickest and most effective solution is to use a chemical spray.

Choosing the right chemical control for the job

The first task when applying a garden chemical is to first identify the weed, pest or disease you want to control. And then research the most effective active ingredient for that problem. If possible use a specialist chemical, one that is specific to the problem.

It’s a bit like taking yourself to the Doctor with an infection. Your GP may prescribe a general antibiotic in the hope that the pathogen that’s making you ill, will succumb. However, some bacteria or fungi don’t respond to just any old antibiotic. There are specific pills for specific bugs.

It’s the same with garden chemicals. For example a general purpose fungicide is unlikely to be effective against red thread disease in your lawn. Conversely, a universal herbicide will damage all of your favourite plants as well as the weeds. And an overall pesticide will devastate pollinating insects as well as aphids.

It’s important that before you look for chemical controls, you must really know your foe and only target plants, microbes or insects that are actually causing damage.

Application rates matter

The chemical that actually does the work for you is called the active ingredient. The active ingredient must be applied in the right quantities and at the right time. A farmer or horticulturist will buy concentrated spray, dilute it with the correct ratio of chemical to water and then spray a prescribed amount on to an area of land. Eg 2 litres of diluted spray to 1 hectare of land.

In garden centre chemicals, the active ingredient is often pre- diluted – in other words, the pre-mixed spray is weak. The manufacturers are assuming that whoever is applying the spray is untrained and therefore they try to make the product as safe as possible. Unfortunately, unless you are an excellent judge of application rates, the dilution rate means that the spray may be less effective. With fungal diseases and insects, any organisms that are not destroyed by the first application of spray are likely to breed chemical-resistant offspring. Which in the long term is not helpful. (it’s the equivalent of antibiotic resistant bacteria in the human or animal worlds)

Trained professionals however, have access to less dilute and therefore more effective sprays. In some cases we can also buy specialist sprays that are not readily available to the general public.

Risk assessments and risk management

Each chemical herbicide, fungicide or pesticide carries its own set of risks dependent on the active ingredient.

If you want to use a chemical control it’s vital that you make yourself aware of all the little foibles BEFORE you buy it. Is it safe to use around pets? How should it be stored? Does it need time to dry onto the plants before it can take effect? Should you avoid using it in hot weather? How long does it take to work? Can it be used on edibles? If so, can you harvest food crops straight away or do you need to leave a period of time between spraying and eating?

Lots of questions but trust me, they are all very relevant.

Not sure? Don’t use it! Bring in the professionals and take note of their aftercare advice.

Caring for the environment

There are strict laws for farmers and other professionals that relate to the use of chemical controls in sensitive areas. A trained professional will never spray certain chemicals near to water courses or close to livestock and they will never apply spray if there is any risk of wind drift. It worries me that the only restriction for garden centre sprays is common sense.

We also have very strong guidelines on disposing of packaging, storing chemicals, and cleaning out our sprayers and other equipment. What’s the sense of avoiding watercourses and then flushing chemicals down the drain?

Caring for yourself

If you are killing pests, diseases or weeds you can be sure that the chemicals used are toxic – at least to the organisms being targeted. All agricultural chemicals have been rigorously tested to ensure that they do minimal damage to the environment and everything in it. However, when you are getting up close with concentrates you could be vulnerable. Especially if you are sensitive to any of the ingredients.

Always wear protective clothing when you are spraying your plants.

A white boiler suit with a hood so that you can spot any spills as soon as they happen.
A mask for your nose and mouth to reduce the risk of inhaling fuels or microdroplets.
Gloves of course and goggles to protect your eyes.

You might feel very hot and look like an alien but that’s better than the alternative!

Getting best value from chemical controls

Use the right chemical for the job. Some professional grade chemicals are very specific whereas garden centre sprays tend to be more general

Handle all chemicals with extreme care. Wear protective clothing
Never mix chemicals – they may react with each other in unexpected ways
Follow the manufacturers’ recommended application rates to the letter. No more, no less. If you’re not sure how to work out the proportions of concentrate and water– ask.
Clean up spills quickly and carefully. Use sand or cat litter to soak up any liquid – never wash it down the drain.
Work with the weather. On windy days you can soon waste a lot of valuable chemical by letting it blow all over the place
If possible, spot treat weeds rather than applying a blanket spray.
Investigate more environmentally friendly solutions before paying for chemicals. Eg biological controls or simply tolerating a few aphids on your roses.
Dispose of all packaging responsibly
Employ the services of a trained professional. When you consider things like protective clothing, more effective chemicals, secure storage and legislation, it’s probably more cost effective than treating the problem yourself. It’s definitely safer.

Having problems with pests and diseases in your garden?

Chris at Keep It Green Garden Maintenance is a fully qualified to treat garden pests and diseases using chemical controls. He has a good knowledge of chemical controls and plenty of experience at applying them. If you need help to control weeds, pests or diseases in your garden, please don’t hesitate to get in touch.

Contact Keep it Green Garden Maintenance

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