6 Natural and Homemade Pest Sprays

6 simple homemade pest sprays you can make yourself using ingredients from your home and garden, to repel and remove leaf-chewing and sap-sucking insects and help with fungal infection.

When it’s hot out in the garden, pests and diseases can take hold. Prevention is the best control for many of them, as well as companion planting and effective feeding and mulching of your plants to ensure they are healthy. A healthy plant is much more likely to survive or avoid attack from pests.

Your first priority in the quest against bad bugs should be ensuring a healthy garden. A healthy garden with a well-rounded eco-system will also be less subjected to an attack of bad bugs because a healthy garden has healthy plants and an abundance of beneficial insects which provide free biological pest control and pollination.

However, if you have an infestation of a bad bug in the garden, or you want to avoid fungal infections, here are 6 homemade sprays you can make with ingredients in your home and garden.

The sprays below will kill only the insects that eat the leaves of the plants or suck the sap.

There are insecticides like derris dust that kill all insects on contact, say if a bee landed on a freshly dusted leaf, and are therefore super harmful to the beneficial insects as well (bees, ladybirds, lacewings…)

As a general rule when spraying any insecticide, leave it until early evening when the bees have gone back to their nests and, avoid spraying flowers. Always take to care when spraying that it’s only on the insects you want to get rid of and not the good guys. Learn to recognize beneficial insect eggs or know where they might lay them to avoid those spaces.

Rhubarb Leaf Spray


We all know to the eat the stalk of the rhubarb but not the leaves. Why?

Because the leaves are toxic. They contain very high levels of oxalic acid which if we consumed, would cause severe kidney damage. We can, however, use this to our advantage by creating an all natural insecticide as this oxalic acid will deal with insects too.

Roughly chop up about 5 large rhubarb leaves and bring to boil along with 1 litre of water. Let it cool down before straining off the liquid and pouring it into a spray bottle along with 1 tablespoon vegetable oil.

Garlic or Onion Spray


Garlic and onion are great deterrents for pests. They both have such strong scents that that will actively repel pests from coming on to the plants. They’re also full of sulphur which will kill insects if it’s sprayed on them.

They make an effective spray for all leaf chewing insects including the caterpillar of the white butterfly.

Crush or whizz up 5 cloves of garlic, or 1 large onion and combine with 1 litre of boiled water. Leave to cool down and steep before straining. Add in a tablespoon of vegetable oil to help the spray stick to the leaves of the plant.

Chilli Spray


Similar to the garlic or onion spray, a chili spray will help repel leaf-chewing insects.

Add one teaspoon of dried chili powder/ flakes, or 2 crushed whole chilis to 1 litre of water, along with 1 tablespoon vegetable oil. Be very careful making this one and wear gloves as chili can burn your skin and eyes if accidentally touched.

Simple Soap Spray


A simple horticultural soap spray will kill bugs like aphids mealybugs, mites and whitefly and other soft-bodied insects when it is sprayed on them. Mix 1 tablespoon of natural dish soap in 1 litre of water along with 1 tablespoon vegetable oil.

Tomato Leaf Spray


A simple solution of soaked tomato leaves in water will help deal with aphids. Tomato leaves and all leaves from the nightshade family contain alkaloids which are toxic to aphids. The strong scent of the tomato leaves will be an attractant to beneficial bugs too.

Leave two cups of chopped tomato leaves to steep overnight in a litre of water. Strain and add in a tablespoon of vegetable oil.

Milk or Baking Soda spray


Both of these work well as a fungicide, particularly to slow down and lessen the severity of powdery mildew. If you are growing cucurbits, the chance of powdery mildew hitting them at some point this summer is very likely but spraying preventatively with milk or baking soda will lessen the severity and hold it off for longer.

For the milk spray add 100ml milk to 1 litre of water along with a teaspoon of vegetable oil.

For the baking soda spray, 1/2 a teaspoon to a litre of water with a teaspoon of vegetable oil.

During summer spray your leaves of your curcubits every 3-4 days in the evenings, until the leaves are completely covered.

Happy Gardening!

This blog post was kindly provided by Elien who lives in Wellington. 
instagram: home_grown_happinessnz

Greg Lowe