Six ways to make your own cost-effective, organic garden spray

You can end up spending a fortune buying the remedies to safeguard your plants. While readily available, organic sprays don’t come cheap – if you’re not careful, those $2 heads of lettuce have cost you $5 extra in protection money. It feels that in an age where we demand a readily available solution to everything, we are losing one of the vegetable gardener’s primary skills: that of resourcefulness.

Making homemade sprays to protect and clean your plants is a skill as ancient as gardening itself. Using simple combinations of basic household ingredients, you can concoct a spray to treat almost anything. Here are a few that you should definitely have in your repertoire.

Hot tip

We are most certainly people of science, and for that reason we always encourage gardeners to use organic material. Growing food without the use of chemicals, particularly when dealing with pest and disease, will ensure we keep nature’s balance in check. Don’t forget that nature has a way of helping out in times of need, so waging chemical warfare that takes out everything will leave your veggie patch more susceptible to future attacks.

Soapy Spray

Shelf life 1 month

Aphids | Whitefly | Thrip | Caterpillars

How to make

Mix 1 tablespoon of biodegradable dishwashing liquid with 1 teaspoon of cooking oil in 1 litre (34 fl oz/4 cups) of water.

How to apply 

Spray over the foliage of plants, particularly on the underside of leaves where the pests often live.

Milky Spray

Shelf life 24–48 hours

Powdery mildew | Honeydew

How to make 

Mix 1 part full-cream (whole) milk to 10 parts water.

 How to apply

Spray on young and affected growth every week.

Garlic and Chilli Spray

Shelf life 2 weeks

Aphids | Whitefly | Thrip | Some possums | Snails and slugs

 How to make

Combine 6 garlic cloves (crushed and roughly chopped), 10–12 chillies (thinly sliced) and 1 tablespoon of biodegradable dishwashing liquid into 1 litre (34 fl oz/4 cups) of boiling water (use a glass jar). Let it soak for 24 hours and then strain into a spray bottle for use.

How to apply 

Spray on the foliage of the affected plants, repeating the dosage after 3 days.

Nettle spray

Shelf life 4–6 weeks

Aphids | Leaf miners

How to make

Soak nettles in a large tub of water for approximately 1 week.

How to apply 

Use the liquid undiluted on the foliage of the plants. This also doubles up as a great plant tonic.

Coffee Spray 

Shelf life 2 weeks

Snails and slugs 

How to make

Mix 1 part espresso coffee (the hard stuff) to 10 parts water.

 How to apply

Apply to leaves of affected plants as well as the surrounding soil.

Bi-Carb Spray

Shelf life 1 month

Powdery mildew | Rust | Honeydew

How to make 

Mix 1 teaspoon of bi-carbonate of soda (baking soda), 1 teaspoon of cooking oil, 1 tablespoon of biodegradable dishwashing liquid and 1 litre (34 fl oz/4 cups) of water.

 How to apply

Spray on young and affected growth every week.

This is an edited extract from Grow. Food. Anywhere. by Mat Pember & Dillon Seitchik-Reardon, published by Hardie Grant Books. RRP $45 and is available in stores nationally.

What type of pest do you encounter in your garden the most?