With global warming on everybody’s mind, there is a concerted effort to reduce waste, save water, and decrease carbon emissions. Most people are looking for ways to make a difference in their own home, but many do not realise there are even more opportunities in their own backyard.
Believe it or not, the average garden is screaming out for help to become environmentally friendly. One of the most common problems with typical Australian gardens is their water use.
Approximately 25% of domestic water is used in the garden, but a few alterations can drastically decrease this usage. Water can be saved by treating the garden soil, adding mulch to the garden beds, installing an irrigation system and creating a good design.
Soil is the saver
Healthy soil will hold water in the root zone where it is needed most. To ensure soil is of a high quality it needs organic matter such as mulch, compost, manure and grass clippings.
Worms will break this matter down to make food for your plants, and their burrows allow air into the soil so plant roots can breathe.The worms eat the organic matter while the plants absorb the nutrients, so organic matter needs to be replaced regularly.
Without sufficient organic matter the soil can become like concrete in the summer and very sticky in the winter. There are generally three main types of soil: clay, loam and sandy. The soils capacity to hold water depends on the type of soil.
To improve the condition of your soil you need to know the type of soil you have. If you are unsure, take a sample to your local garden centre and they should be able to tell you.
Finally, don’t cultivate your soil unless it is very compacted after construction work. Cultivating the soil will affect the natural structure of the soil, disturbing the air holes and drainage spaces.
Caring for your soil
Clay soils
• Retains nutrients and water
• Poor drainage
Sandy soils
• Contains little organic matter
• Allows infiltration and drainage of water
Loam soils
• Holds a moderate amount of nutrients and water
• Ideal for growing plants
Consider compost
Compost is one of the most effective and affordable sources of organic matter that you can add to your soil. You can create your own soil-enriching compost from grass-clippings, food scraps, newspapers and garden prunings.
Regularly digging compost will enable your soil to hold water and will provide valuable nutrients for your plants. Similarly, mulch will conserve the soil moisture and reduce the amount of water used in the garden and on your pots.
On a hot day, up to 73 per cent of water can evaporate if you do not have a protective layer of mulch on the surface. As mulch breaks down it will also add nutrients and prevent weed growth.
Different types of mulch
Pea straw and Lucerne
• Use pea straw and lucerne if you haven’t mulched the soil for a long time. It’s easy for the worms and breaks down quickly
• Pea straw and lucerne are ideal for veggie gardens
Hardwood chips with no fine chips
• Ideal for ground cover as they allow air flow and let water freely through to the ground
Mulch with fine grade material
• Has a tendency to clump and repel water
A green design
When designing a “green” garden the overall design should be the first thing you think about.
Gardening should always be fun; however, it is also necessary to consider the overall look of the garden and how the garden design can be used to reduce water wastage.
Many people still have a fairly traditional English-style garden with a large expanse in the middle—ideally designed for the family game of cricket—and flowerbeds around the outside.
Unfortunately, this design tends to use a lot of water and fertiliser. Simply, by replacing “thirsty” flowers and plants with varieties that require less water you will decrease the water consumption of your garden.
Then, gradually extend your garden bed to reduce the expanse of water-thirsty lawn. In the high traffic areas where the turf may be already worn, consider replacing the lawn with paving or gravel.
If re-designing your garden from scratch, there is great potential to create a sustainable garden that is colourful, interesting and water smart.
When designing your new garden consider the size and type of garden area you want and are able to maintain. Consider how much time you will be spending in your garden and what it will be used for. Whether it will mainly be an entertainment or a play area for the children and pets, these factors will determine the design and the types of plants to use.
Helen’s top tips
Helen Tuton is a soil scientist and a garden centre co-ordinator for Sustainable Gardening Australia. She knows that the key to a good garden is in the health of the soil.
“It is often overlooked, but the greater the organic matter, the better your plants will look and, if edible, taste. You will save water also.”
Her second number one tip for sustainable gardening is to diversify your planting. “If you are planting a veggie patch, include flowers as well. The flowers will attract beneficial insects that will get rid of the bad insects. This will help the environment because you won’t have to spray with chemicals. Yellow flowers are always good and flowers that will flower much of the year. Include plants that drop leaves and have logs around the place. This will attract lizards and skinks. Again, they eat the bad insects in the garden so you won’t have to use harsh chemicals”.
Grey equals green
Domestic wastewater, or greywater, comes from a household’s laundry and bathrooms and is an often-untapped resource.
Re-using water that comes from the laundry and bathroom is an excellent way to save water and it’s available every time you wash.
Greywater is not always best to use on your garden beds. You should avoid using it when there will be high levels of phosphorous, bleach and fats (from soaps).
Similarly, even though water from the kitchen is called greywater, it is not suitable for the garden because of the food particles and fats.
Health concerns when using greywater
• Don’t use nappy wash water
• Don’t let children play in the water
• Don’t let pets drink the water
• Avoid applying to edible parts of vegetables
Tips for saving water in the garden this spring
1. Install a rain water tank that is suitable for your watering needs and the position of your down pipes
2. Use a drip watering system or porous hose which ensures water only goes where it is needed and therefore reduces wastage
3. Avoid micro-sprays as they waste up to 70 per cent of water through evaporation and drift. If the soil is mulched then the spray will not be able to penetrate.
4. Fit tap timers to make sure you don’t over-water and use rain or soil sensors in your garden so watering doesn’t occur when the soil is wet
5. Use an inverted soft drink bottle to slowly water annuals, ferns and roses
6. Use soil wetting agents to hold water in the soil longer and closer to plants
7. Use mulch on the garden beds
8. Plant wind breaks to reduce the wind drying effect on the garden bed
9. Choose local plants that have lower watering needs and suit drier conditions
10. Remove weeds from the garden as they compete with plants and lawns for water
11. Put an ice-cream container on the lawn or garden when watering. When the water in the container is 10mm deep you have watered for long enough.
Lawn alternatives
During times of water restrictions and low rainfall the traditional turf lawns can become brown and unsightly. However, there are a number of other turf options that use less water, for example, Sir Walter Buffalo.
If you prefer clumps of grass then you may like kangaroo grass (Themeda triandra) is a great alternative. You may also want to consider native grass; lawn or weeping grass (Microlaena stipoides) which looks like a traditional lawn. Weeping grass can be mowed regularly and grows well in a wide range of soils.
Alternatively, groundcover plants can be used to form a dense mat. They don’t require mowing and grow well in the shade. Examples include the kidney plant (Dichondra repens), creeping boobialla (Myoporum parvifolia) and native mint (Mentha diemenica).
If you want to replace your lawn altogether, gravel, granitic sand or pavers are becoming increasingly popular.
If laying pavers it is important to use permeable pavers to allow excess water to seep through. Otherwise direct water onto garden beds or keep in place by planting mondo grass in between the pavers.
Low water use plants
There is a huge range of plants that use a limited amount of water – some indigenous to Australia and others from around the world.
Plants can be mixed and matched to create an interesting and diverse garden. Ensure the plants are not environmental weeds and have similar soil and water needs.
Australian natives are suited to drier conditions and a wide range of soil types. Examples of native plants include the Eucalypts, Wattles, Banksias, Bottlebrushes (Callistemon spp) and Kangaroo Paw (Anigozanthus spp).
Over the last few years, succulent and foliage plants have increased in popularity because of their limited need for water. Succulent and foliage plants are able to grow in containers and look fantastic in contemporary style gardens. Examples of succulents include Yuccas, Cycades, Agaves and various Flax plants.
Plants with grey or silvery leaves handle warmer conditions really well and add an interesting texture and foliage. Examples include Lavender, Westringia, Lambs Ears (Stachys byzantina) and Bearded Iris.
Plant Tips
• Never plant in summer. Autumn is ideal.
• Indigenous, natives and exotic plants can be used together to create a really beautiful, successful garden. Consult with your local gardening centre during the planning stage
• There is a perfect tree for gardens of all shapes and sizes. Trees provide shade, oxygen, munch up carbon emissions, provide leaves for mulch, a habitat for wildlife, and can even provide fruit.
Beautiful dangers
Toxic for the kids
• Duramta
The seeds are toxic if consumed
• Sweet Peas
Beautiful flowers but the peas are toxic if consumed
• Agapanthus
The sap is toxic and can cause a skin irritation
• Arum Lilly
The sap is toxic and can cause a skin irritation
Toxic for your pets
• Bulbs are toxic.
• Lilies may cause an oral irritation
• Avocado Trees
• Macadamia trees
• Aloe Vera
If consumed your pet may experience serious stomach upsets, vomiting and diarrhea.
by Sarah Dunstone
Article provided by The Retiree Magazine