Random thoughts from a curious gardener

Having developed more of an interest in plants and gardens since moving to Leisure Isle, and having more time to read and think about the different approaches to creating gardens – I find myself puzzled by certain aspects of gardening.

One, for example, is why basically gentle, caring people like gardeners use highly toxic pesticides to protect their plants from certain insects – and at the same time risk poisoning young children, pets, not to mention affecting their own health, and killing many insects that are beneficial to these same plants? It is not as if there are no other alternatives to preventing plants from being chomped by hungry aphids, caterpillars or snails.

 Companion Planting ~ photo Margaret Richards
Companion planting
photo Margaret Richards

How and why did gardeners come to be so dependent on toxic products?  Have we become more impatient than our grandparents? Has the ‘fast food’ syndrome of the last part of the 20th and beginning of the 21st centuries driven the desire to create ‘instant’ and ‘perfect’ gardens? Or do we use such products simply because they are available? The range and availability of these toxic products is incredible and they promise the annihilation of every shape and size of ‘gogga’ imaginable.

Apparently the massive chemical fertilizer industry, along with the accompanying pesticide and herbicide industry, developed after World War 2. This was because after the war the USA had a huge surplus of ammonium nitrate – used for making explosives. This also happens to be an excellent source of nitrogen for plants – so the redundant munitions plants were turned into fertilizer factories. The production of pesticides and herbicides was added to the industry – many being based on poison gasses developed by the military. (Remember Agent Orange, used in the Vietnam War to destroy the tropical vegetation?)

First farmers and then gardeners were encouraged to use mainly the Big 3 (Nitrogen, Phosphorus and Potassium) – to improve plant growth. Subsequent research has shown that a much wider range of trace elements or micronutrients is actually needed for the health and growth of plants. Regular use of only the Big 3 has slowly depleted the soil, leading to unhealthy plants vulnerable to disease and attack by pests.  This is turn leads to the use of ‘quick fix’ toxic pesticides.

How to manage without toxic pesticides? The first step seems to be to cultivate a healthy nutrient-rich soil where healthy and strong plants will be able to grow and resist disease and ‘goggas’. Other steps include companion planting, encouraging beneficial insects, earthworms etc. There are numerous books which cover these topics.  An excellent one is Jane’s Delicious Garden: how to grow organic vegetables and herbs in South Africa, by Jane Griffiths. Cape Town, Sunbird, 2009.


So while you enthusiastic gardeners are busy finding out more, here are 2 recipes for natural insecticides made from common plants and kitchen ingredients: – Marigold spray: Mash 2 cups of marigold flowers and leaves in a litre of water. Soak for 24 hours. Strain and add 1 Tablespoon of dishwashing liquid. Dilute 1 part mix to 1 part water before spraying the plants. Will keep in the fridge (suitably labelled!) for a month. Used as a general fungicide and insecticide.

Tomato spray: Boil a handful of torn up tomato leaves and or stems for 20 minutes. Strain and allow to cool before use.  Does not keep. Very effective for scale or aphids.


By Leonie Twentyman-Jones