Here are some DIY pest control tips on reducing your chemical use on your lawns. These DIY pest control lawn tips are for natural homemade fungicides, natural fungicides, non-toxic weedkillers and/or homemade weed killer. This article dovetails nicely with our blog on using biostimulants.

We all say we are going to do the right thing but in reality, is that the case? Taking care of our environment is important and part of this is trying to reduce our pesticide and fertilizer use. That doesn’t mean we are saying stop using what we call “hard” chemistry but in some instances, there are alternative options that you can look at.

Consider this.

  • A recent UN report on pesticides leaching into waterways makes for pretty grim reading.
  • Pesticides found in waterways in Ireland include MCPA (commonly found in Australian lawn weedkillers).
  • A 2020 study in French vineyards concludes… “the improper use of Plant Protection Products for grapevine cultivation may cause groundwater contamination”… This is after chlorantraniliprole (the active in Acelepryn) was found in the ground water.

DIY pest control tips – Fungicides

All of the following are natural fungicide recipes to make your own homemade fungicides. These are mostly based on common household ingredients you can find around the home. Many of these natural fungicides will surprise you. However, do realise that sometimes, under high disease pressure, you may need to use stronger lawn fungicides based on “hard” chemistry.

Baking soda or potassium bicarbonate

Ecocarb and Ecocarb Plus (OCP) both contain the natural fungicide potassium bicarbonate. However, they are not registered for lawns. Having said that, both baking soda and potassium bicarbonate do work well as a homemade fungicide on turfgrass. A product called Amicarb is registered in the USA for anthracnose, brown patch and dollar spot.

It’s easy to make your own homemade fungicide based on these ingredients. They work by creating an alkaline (high pH) conditions at the turf surface. This prevents the growth and spread of fungi. Personally I’d suggest you use potassium bicarbonate in your homemade fungicide rather than sodium alternative for obvious reasons.

To make this at home you can add a tablespoon of baking soda to 5 litres of water. Spray this every three days until the fungus dies.

Neem Oil

Neem oil is also an effective natural fungicide. To make a homemade fungicide containing neem, mix two tablespoons of neem oil and 4L of water. Shake the mixture well and spray it on turf, making sure to get good coverage. This homemade fungicide recipe is particularly effective against rust, anthracnose, and leaf spot.

Papaya milk

Indian work has shown that papua milk is an extremely antagonistic natural fungicide vs Rhizoctonia Solani which causes damping off. Where you get papaya milk from in Australia I have no idea.

Vinegar

Vinegar is a natural acid that creates an acidic environment on the plant’s surface, which then helps to prevent the growth and spread of fungi.

To make a homemade fungicide using vinegar, mix 50ml of apple cider vinegar (or white vinegar) to every 1L of water. Shake the mixture well and spray it onto your lawn, making sure to thoroughly cover your target.

Milk

Milk is an excellent natural homemade fungicide thanks to its antifungal properties. It contains lactic acid, which reduces the pH of infected plant tissue thus making it uninhabitable to many fungal species. As this is in nearly everyones home, itT is an excellent option as a homemade fungicide.

he other cool thing about milk is that it also contains compounds that may disrupt the fungal cell wall or interfere with fungal respiration.

To use milk, mix 1 cup of milk with 10 cups of water, and then spray this onto the infected turfgrass. You should aim to reapply this every few days until the problem clears up.

Chamomile Tea

Work has shown chamomile oil is a very effective natural fungicide vs damping off caused by Rhizoctonia solani.1Emara AR and Morsy AR, Antifungal activity, phytochemical analysis and chemical composition of Chamomile (Mtricaria recutita L.) essential oil against Rhizoctonia solani and Fusarium solani, Middle East Journal of Agriculture Research, Volume : 07 | Issue : 04 | Oct.-Dec. | 2018 Pages:1849-1855 

To make a chamomile tea natural fungicide, soak four chamomile tea bags in one litre of hot water for 30 minutes. Remove the tea bags and add a litre of cold water. Shake the mixture well and spray it on the turf, making sure you get good coverage. This recipe is very good against damping-off and root rot.

Cinnamon

A good natural fungicide recipe using cinnamon is to Mix one tablespoon of cinnamon powder to 4L of water. Shake the mixture well and spray it on the turf. Make sure to thoroughly cover the grass.This recipe works against damping-off and powdery mildew.

Black Cumin Oil

This has been shown to be very effective against damping off cause by Rhizoctonia Solani in tomatoes2Hamza A, Mohamed A and Derbalah A, Unconventional alternatives for control of tomato root rot caused by Rhizoctonia solani under greenhouse conditions, Journal of Plant Protection Research, Vol. 56, No. 3 (2016) pp298-305

Hydrogen Peroxide

Hydrogen peroxide is a natural disinfectant that helps control fungal diseases in turf.  The natural fungicide recipe usig hydrogen peroxide is to mix use 3% hydrogen peroxide and mix one tablespoon in 4L of water.

Shake the mixture well and spray it on the plants, making sure to fully cover the entire area. This recipe is particularly effective against root rot and damping-off.

Tea tree oil

Tea tree oil is a natural antiseptic and fungicide that can help control a wide range of diseases. The natural fungicide recipe for this is to mix one tablespoon of tea tree oil and 4L of water.

Soil Wetting agents

Some but not all soil wetting agents can help manage or reduce turfgrass disease. We think that they achieve this by reducing leaf wetness which in turn prevents moisture being present to encourage disease. Products such as Hydroforce Ultra are worth having a look at if you want to go this way.

Using milk as a fungicide
Apple cider vinegar is an excellent natural fungicide
Black cumin oil is an excellent DIY fungicide against rhizoctonia
baking soda can be used as a non toxic weedkiller

DIY pest control tips – Insecticides

These are all options for homemade insecticides. These can also be classed as organic insecticides. 

Iron chelate

Iron chelate is an excellent homemade insecticide for controlling slugs. Interestingly Iron EDTA chelate kills more slugs compared to commercial slug killers, and that’s without any non target toxicity effects! Its a great DIY pest control option.

Neem oil

Neem has historically been used as a homemade insecticide and works really well as a natural insect killer. It is most effective against insects, which pass through all stages of metamorphosis and works best as a long lasting systemic insecticide when used as a soil drench. The oil is a thick, “fatty” oil, and has a very strong odor.

Eco-neem is a registered natural insect killer for the control of a broad range of insects including: caterpillars, curl grubs, grasshoppers (wingless), aphids, mites, lawn armyworm, citrus leafminer, whitefly, mealybugs and fungus gnats in soil.

Neem works in two main ways:

  • Firstly it suppresses insect appetite so they starve to death and secondly
  • They are unable to moult successfully. Plant damage stops as soon as the insect ingests eco-neem. Plant damage will stop but death may take several days depending on the size of the target insect. 

Washing up liquid

This is one of the best natural insect killers. It’s in every house and works really well as a homemade insecticide. Its excellent as a homemade miticide. However, you have to be careful not to add too much soap to the water.

Th recipe for a homemade insecicide using washing up liquid is:

  • Use mild washing up liquid.
  • Add 1 and a half teaspoons of soap per Litre of water.
  • Mix this properly and then pour this mix into a pump pack/spray bottle.
  • Spray the lawn aiming to get complete coverage.
  • Never apply during the heat of the day or when plants are in direct sunlight. So it’s best to spray this in the early morning or evening.
  • Repeat the application every 4-7 days. As it isn’t rainfast after heavy rain it will need reapplying. Continue this until you start to see an improvement.
  • Don’t forget to test first.

You will get best results with this Insecticidal soap when it is dissolved in soft water. The reason for this is that in hard water the fatty acids conatined in soap tend to precipitate out.

Vegetable Oil

Using vegetable oil is an effective way to get rid of turf mites. The soap and oil combo coats their bodies and they suffocate to death.

Th recipe to use vegetable oil as a homemade insecticide is:

  • Use 1 tablespoon of mild soap (like washing up liquid) to 1 cup of vegetable oil. Mix well.
  • Add 2 tablespoons of the oil mix to a Litre of water and pour into a spray bottle.
  • Spray to fully cover the lawn.
  • You’ll probably have to stop and shake the mixture a few times during application to make sure the soap, oil, and water are mixed.
  • Do not ever apply to plants in direct sunlight or when the heat of the day is at its highest.
  • Aik to apply this every 4-7 days or after heavy rain or if you irrigate.
  • As with all of these mixes don’t forget to test first.

Coffee

A 1 to 2% solution of caffeine will kill slugs and snails.  Concentrations as low as 0.01 percent repel them.

Coffee grounds can also be used to repell slugs and snails but a caffeine solution is much more effective. Caffeine is more effective against slugs than metaldehyde products.

Dealing with mites

Mites can be a problem for both turf and garden plants. These tiny pests can cause a huge amount of damage in a short time so they need dealing with as soon as a problem occurs. There are a lot of miticids available on teh market and probably the best is Malice Duo. However, if you want to look at controlling these pests more naturally I would start by not using pyrethroid based insect sprays (e.g. bifenthrin) as thse can in fact worsen the problem. Not ony do these kill any natural predators but tehy also cause something called “mite flare”. This is when there is a surge in population following a spray.

As we mentioned earlier Neem works against mites but another option is to use apple cider vinegar. A good homemade insecticide recipe using vinegar is: mix a 3 tbsp vinegar, 1 tbsp baking soda and a few drops of liquid washing up liquid soap in 1ltr of  water. You then apply this liberally to the effected area. Always remember that if it rains or you irrigate etc this will need reapplying.

Rosemary Oil

Research has shown that this is very effective against mites3Miresmailli S and Isman MB, Efficacy and persistence of rosemary oil as an acaricide against twospotted spider mite (Acari: Tetranychidae) on greenhouse tomato, J Econ Entomol . 2006 Dec;99(6):2015-23. doi: 10.1603/0022-0493-99.6.2015..

A good natural insecticide recipe using rosemary oil is:

  • Dilute a tsp of rosemary oil in 1ltr of water and fill a spray bottle.
  • Spray generously on the plant’s stems and leaves, paying extra attention to the undersides.
  • Repeat daily as necessary.

Rhubarb spray

Rhubarb leaves contain oxalic acid, which makes a great natural pesticide for leaf-eating insects. To use this at home as a homemade insecticide, collect some fresh rhubarb leaves and boil them in water. Once the solution has cooled, transfer the solution into a spray bottle. Add a splash of dishwashing soap and spray on affected leaves.

Companion planting

Around the garden planting certain plants like European dill, Chinese parsley, Chrysanthemums, Shasta daisy, and peppermint. Peppermint contains pulegone and menthone, which are effective at repelling pest insects. Menthol, a which is in peppermint, shows significant promise against the two-spotted spider mite.

washing up liquid is an excellent option for DIY pest control as a homemade miticide
coffee works really well as a slug and snail repellant and is perfect for DIY pest control
vegetable oil works well as a homemade insecticide

DIY pest control tips – homemade Weed killer

You can use all of these as homemade weed killer or non toxic weed killers that you can make with common household items. This is THE list for natural weed control.

Nigrospora oryzae 

Having said that the first cab off the rank as a DIY pest control isn’t actually a homemade weed killer but it definitely can be classified in the non toxic weed killers section! A natural fungus that eats Parramatta grass and is native to Australia. Relax its not a “The Last of Us” type fungus! These are all safe to use options for natural weed control around the garden.

Nigrospora crown rot fungus is caused by the natural (endemic) fungus Nigrospora oryzae. As a result it can be called a completely non toxic weed killer and only targets this grass weed. The disease basically eats giant Parramatta grass (GPG) and reduces infestations over a couple of years. Up to 78% reduction in tussock size (over 15 months) and 64% reduction in tussock presence (over 12 months) has been observed in the field. Sadly it isn’t registered but if you can find some contaminated parramatta grass you can wash off the sporres and spray these onto the target weed.

Sugar as a non toxic weed killer

Sugar works pretty well as a non toxic weed killer and homemade weed killer. It causes the grass and weeds to fight over limited nitrogen in the ground. Yes good old obesity causing sugar, is an excellent homemade weed killer which works well against juvenile broadleaf and annual weeds. You can use granulated or powdered sugar sprinkled lightly over your lawn, aiming to evenly coat the lawn and water it in lightly.

The use of sugar as a non toxic weed killer is supported by researchers at Charles Sturt University who found that sugar provides a good, short-term non-chemical and ecologically friendly method of weed control.

One other cool thing about using sugar as a homemade weed killer is that it kills yellow nutgrass. Sprinkle sugar onto the plant 3-4 times and bingo!

Ammonium sulphate

Lawn sand is a traditional greenkeepers weed and moss killer. This non toxic weed killer works by “burning” them out of your lawn. It’s simple enough to make this homemade weed killer, as all you need to do is mix 65 parts ammonium sulphate with 35 parts dry sand. This mix works really well against daisies, plantains and also moss.

Vinegar

Good old vinegar again! This is a cheap low cost non toxic weed killer. A US study looked at summer grass control in buffalo grass, using 30% acetic acid, and sodium bicarbonate. The conclusion was that because of high turfgrass injury and little residual control, that these are not an effective substitute for using pre-emergence herbicides for summer grass control like Echelon Duo or Onset 10GR.

Having said that vinegar does work as a homemade weed killer although it is non selective (it kills everything!). You can also use it to buffer your spray water

This is a good natural weed killer recipe using vinegar as a non toxic weedkiller which gives non-selective weed control. Add 30ml of orange oil and 1 teaspoon of liquid soap per 4L of 10% concentration of vinegar.

Iron

FeHEDTA (iron chelate) can be used as an effective homemade weed killer. Being selective this means it controls broadleaf weeds but does not harm the grass. This works quickly, and gives same-day results, even in cool weather.

Although it is a non toxic weed killer this isn’t the case if you are a broadleaved weed. Broadleaf weeds absorb chelated iron easily and in larger quantities than grass. This then causes weed death while the grass remains unharmed. Be sure to fully cover the weed to get the best results.

It has to be FeHEDTA though!

Sodium bicarbonate/baking soda

The final homemade weed killer is baking soda. You can use this for summer grass control and as a non toxic weed killer. Simply put some in an old sock and whack the sock onto damp summer grass to dust it on. After a few days the weed blackens and dies.

It works due to its alkaline properties drying out the weed which then kills it. To combat summer grass, water the weeds with a hose or watering can. Once the summer grass is wet, apply a hefty whack of baking soda. Try and do this on a sunny day, as the drying effect of the baking soda will work really well.  The weed’s then dry out under the heat of the sun.

So there we have our list of homemade weed killers. Please feel free to contact us if we have left any out.

baking soda can be used as a homemade weed killer and non toxic weedkiller
Sugar works as a non toxic weedkiller and is a great DIY pest control option for a homemade weed killer
Nigrospora oryzae can be used as a non toxic weedkiller that can control parramatta grass
Fiesta is a non toxic weedkiller containing FeHEDTA
Apple cider vinegar is an excellent natural fungicide

Although not available in Australia “Fiesta” is a non toxic weed killer sold in the USA based on FeHEDTA. When you use a non toxic weedkiller like this, they will give visible results within 24 hours.

References

  • 1
    Emara AR and Morsy AR, Antifungal activity, phytochemical analysis and chemical composition of Chamomile (Mtricaria recutita L.) essential oil against Rhizoctonia solani and Fusarium solani, Middle East Journal of Agriculture Research, Volume : 07 | Issue : 04 | Oct.-Dec. | 2018 Pages:1849-1855
  • 2
    Hamza A, Mohamed A and Derbalah A, Unconventional alternatives for control of tomato root rot caused by Rhizoctonia solani under greenhouse conditions, Journal of Plant Protection Research, Vol. 56, No. 3 (2016) pp298-305
  • 3
    Miresmailli S and Isman MB, Efficacy and persistence of rosemary oil as an acaricide against twospotted spider mite (Acari: Tetranychidae) on greenhouse tomato, J Econ Entomol . 2006 Dec;99(6):2015-23. doi: 10.1603/0022-0493-99.6.2015.
Jerry Spencer senior turf agronomist and soil scientist
Senior Turf Agronomist at Gilba Solutions Pty Ltd | 0499975819 | Website | + posts

Graduated from Newcastle University with an Hons Degree in Soil Science in 1988, Jerry then worked for the Sports Turf Research Institute (STRI) as a turf agronomist before emigrating to Australia in 1993.

He followed this by gaining a Grad Dip in Business Management from UTS. He has worked in a number of management roles for companies as diverse as Samsung Australia, Arthur Yates and Paton Fertilizers.

He has always had a strong affinity with the Australian sports turf industry and as a result he established Gilba Solutions as an independent sports turf consultancy in 1993. Jerry has written over 100 articles and two books on a wide range of topics such as Turf Pesticides and Nutrition which have been published in Australia and overseas.