Environmental Education

Image of a flower. Sustainable gardening

Sustainable gardening uses natural biological methods to create healthy soil and ecosystems and produce healthy, insect-resistant plants. It is about growing food, flowers, grass and trees based on an understanding of nature.

Why should we bother to change?

Pesticides can be absorbed and leave residue on fruit and vegetables, they can contaminate and pollute the land, waterways and air, and they can damage ecosystems effecting bird and insect life. Similarly, synthetic fertilisers can be detrimental by encouraging a spurt of unhealthy growth that makes plants more susceptible to disease and insects. Many synthetic fertilizers are devoid of the nutrients and trace elements needed to produce healthy plants.

There is a wide range of established alternative gardening practices that can be used to create more sustainable gardens including:

Low water gardening
Developing gardens for shade and shelter
Composting and recycling
Creating an edible garden
Considering biodiversity and seed selection
Looking at pest and disease control
Managing weeds

Quick reference documents on sustainable gardening

Gardening Information PDF (245KB)
Gardening Actions PDF (101KB)

Low water gardening

Reducing water demand is important. Research shows the next 50 years will be less wet than the last 50 and already some water tables are dangerously low.

Ways to reduce your garden water needs:

Know the water demand of different plants and group them together
Reduce the area of thirsty lawn
Water plant roots, not the leaves.
If you install an irrigation system, control it with a timer
Avoid watering in the heat of the day or in windy weather
Improve the soil's capacity to take up and retain water
Use mulch to keep soil moist
Don't over water - check the soil moisture before you water
Use glazed flowerpots or recycled plastic pots instead of porous terrocota pots.

Shade and shelter

Use garden plants for ‘green air-conditioning' to create a healthy environment by:

planning a garden for shade as well as sun.
planting a windbreak to deflect chilling winter winds.

Composting and recycling at home

Reduce the amount of rubbish you pay to dispose of each week by turning kitchen and garden waste into plant food. Compost is the cheapest way to enrich your soil and is made from combining nitrogen-rich green waste (kitchen peelings, cut flowers, vacuum cleaner dust and weeds) with larger volumes of carbon-rich brown waste (leaves, straw, wet shredded paper and small twigs).

The Healthy Edible Garden – producing food naturally

Growing fruit and vegetables is worthwhile for anyone serious about staying healthy and building a sustainable environment. Small scale home gardening can add taste and variety, vitamins and minerals to the household diet, on a modest budget.

A sunny spot and a three-metre square garden can provide a family of four with vegetables year-round while apartment or town house owners with a sunny balcony can grow vegetables and herbs in pot plants.Decide what crops you wish to grow.

Choose robust plant varieties.
Become familiar with organic garden growing techniques that don't rely on chemicals to stimulate growth and kill pests.
Use mixed and companion planting to deter insect pests

Biodiversity and seed/plant selection

Give your garden natural strength by planting a wide variety of plants (even in small urban gardens), attracting native insect eating birds (and keeping cats well fed), attracting other wildlife like butterflies and lizards to your garden, and planting native shrubs and trees that occur naturally in your region.

Pest and disease control: The chemical-free way

Before you reach for poisons and chemicals consider:

planting the crop in a different location and crop rotation.
setting physical barriers and traps to stop pests
introducing a ‘biological control agent'.
making your own pest deterrents.

Weed Management: Keep invasive garden plants out of the bush!

There are 2,400 native plants in NZ and 20,000 exotic plants. Of the 20,000 exotics, 500 are noxious. Each region has a list of pest plants found to be sufficiently invasive in that climate familiarise yourself with these, avoid planting them in your garden and lobby garden centre.

Some files on this page are in Adobe PDF format. You will need Acrobat Reader to view the documents which can be downloaded free from www.adobe.com.