Saving water in the garden

• Water plants early in the morning and late afternoon to reduce evaporation loss.
• Put your finger into the soil and if it is moist below the surface you don’t need to water.
• Check the weather forecast. Let rain do your watering.
• Only water the plant root zone to avoid wasting water where plants won’t use it.
• Watering at dusk after a hot day may encourage fungal disease.

Ornamental trees and shrubs

Trees and shrubs need more watering when they’ve just been planted. As their roots grow deeper, they won’t need as much. Different plants need different amounts of water. For example, many Australian or South African plants may not need any extra water when established, while many exotics plants will.

Fruit trees

Fruit trees need more water and feeding than ornamental plants. Mix plenty of organic matter into the soil prior to planting. This will feed the plants as well as help the soil retain moisture.

The vegetable garden

Growing vegetables need between 25 mm and 50 mm of water per week for good growth. If watering by hand or with a sprinkler, watering about once a week so water soaks to a depth of about 150 mm will often be adequate. Repeat when the top few millimetres of soil have started to dry out.

Pot plants

Groups of plants in containers may be watered as a group by sprinklers or micro-sprays, but the most efficient solution is to use drip irrigation, with individual drippers in each pot. Adjust the flow rate of the drippers to suit each plant’s needs.

Capillary pot watering enables a large number of pots to be watered simultaneously. Pots sit on a porous mat through which water is circulated, to be drawn into the pots by capillary action.

Use small ‘feet’ under container plants, to avoid blocking their drainage holes and causing their roots to rot. Water-absorbing granules mixed into the potting mix reduces the risk of plants drying out and allows longer spells between watering.

Avoid overwatering

Before you water, push aside the mulch, stick your finger into the soil and if it is moist below the surface you don’t need to water.

Many plants are much tougher than you think and will go long periods without additional watering.

Less frequent watering forces roots downwards to find water, making the plants less reliant on surface water and better able to stand hot, dry days.

Strategic watering

Many garden plants are drought tolerant and won't need additional watering once established. Experiment with existing plants - water less, then not at all and watch for signs of stress like wilting and leaf fall.

Think about what this means for manual and automatic watering systems. Does your entire garden need watering? Can you zone plants that need more or less water into areas so you can focus watering on the areas that really need it?

If you have plants that need more water as soon as the weather warms up, could they be moved to a cooler area or protected from drying winds? Could they be replaced with drought tolerant plants this autumn that will have a similar appearance and style? Use the Plant Finder to find the best plants.

Want to water your lawn?

• Don’t water too often. Giving the lawn a proper drink, less often, encourages deeper root growth so your grass will be more able to withstand heat stress and dry periods.
• Don't water too much. Grass is shallow rooted and rarely extends more than 25mm into the soil. Put a 25mm deep tuna tin out when you are watering your lawn and stop when the tin is full. When all the water in the tin has evaporated, it’s time to water again.
• Cut your lawn by no more than a third of the grass length. Leave the clippings on the lawn to form a mini-mulch to retain moisture longer.

There’s plenty of different watering systems to choose from:

Drip irrigation

The most efficient way to water is to water roots, not leaves. Drip irrigation systems deliver water at or below the ground surface. They deliver a controlled trickle of water directly to the roots, minimising evaporation and water loss.

The simplest form of drip or trickle irrigation is a soaker hose, which can be moved around the garden. A semi-permanent trickle system uses polytube feeder lines to deliver water to different plants.

Drip irrigation uses lower water pressures so should be used with a pressure regulator to avoid equipment damage. If you have sandy soils a drip system might not be the most effective watering system.

Filters and backflow valves

Both micro spray and dripper systems are vulnerable to clogging from water-borne debris. Install an inline filter just after the main tap to avoid repeated blocking. Check with your local council to see whether this requires a plumber.

Movable sprinklers, trigger nozzle and watering can

The simplest solution is using watering cans or trigger nozzles so you water only those areas that need it. A hand-held rose, attached to the end of a hose is a movable sprinkler, but during drought, some water restrictions ban the use because water can be lost through wind spray and evaporation.

Fixed sprinklers

Miniature spray heads or jets are mounted onto rigid risers plugged into a network of black pvc irrigation tubing, known as polytube, as feeder lines, usually 13 mm in diameter. This irrigation is prone to wind spray and high evaporation losses and is not permitted under water restrictions in some parts of Australia.

Timers

Timers can turn watering systems on and off. The simplest type is a clockwork timer which is fitted between the tap and the hose line or irrigation system, allowing up to 2 hours of watering before switching off.

More complex computerised units allow several independent lines to be programmed to turn on and off independently, on different days of the week.

A rainfall sensor connected to the timer should be used to cancel the system in periods of high rainfall.

Water wicking

A wicking bed is a garden bed with a waterproof lining which holds a reservoir of water at the base. The water is drawn upwards through the soil via natural osmosis or ‘wicking’ through the damp soil below to the drier soil above to help maintain consistent and optimal growing conditions. Water wicking significantly reduces water waste as none is lost to the evaporation, or the effects of wind and sun.

Rainwater tanks are designed to catch and store rainwater that would have otherwise run down the stormwater drain. They play an important role in saving precious drinking water and managing stormwater in our communities.

A rainwater tank is a great source for operating your sprinkler or water system, provided it isn’t connected to or topped up the drinking water system.

Benefits of using rainwater

• Rainwater saves precious drinking water.
• Using rainwater instead of drinking water in your garden will save you money on your water bill.
• Rainwater tanks are easy to use and available in styles to suit most homes. Select an appropriately sized pump for your tank to operate energy efficiently.
• Rainwater tanks can store large amounts of water which can be used for toilet flushing and clothes washing.  If plumbed properly into your home, you could reduce you drinking water use by up to 40% .Talk to your plumber to find out more.

Greywater is reusable water from washing machines, showers, baths and basins. Untreated, it’s a good source of nutrients for many plants. When its treated, you can also use it to flush toilets and wash clothes.

How to use greywater

There are 3 ways to collect and use greywater.

1. In a bucket
   The easiest and cheapest way to collect grey water is in a bucket from showers, washing dishes or vegetables to water your garden. To prevent bad odours, use the grey water within a day and avoid using grey water when the soil is already saturated
2. Greywater diversion devices
   Greywater diversion devices collect and store grey water to irrigate below soil surfaces. These systems are self draining and should have a valve to divert greywater to the wastewater system when it rains or the soil is saturated.
   NSW Health maintains a register of accredited greywater diversion devices for you to consider.
3. Greywater treatment system
   A greywater treatment system treats and stores all the grey water your home produces. Treated  greywater isn’t drinkable, but you can use it to:
   • flush toilets
   • wash clothes
   • water your garden using a hose, spray or drip irrigation

NSW Health maintains a register of accredited suppliers.

Want to get the best out of your greywater?

• use biodegradable, low phosphate liquid- based soaps and detergents. Your lawn will love it.

Mulching is a great way to save water. Applying several centimetres of mulch can save up to 70% of water lost through evaporation.

1. Remove weeds.
2. Moisten the soil thoroughly.
3. If water is running off the surface fork through some compost.
4. Lay the mulch depending on the type you've selected.
5. Don’t mulch right up to the plant stem as this can cause fungal disease. Leave a gap of at least 4cm.
6. Top up your organic mulch every year or more frequently if the mulch has broken down a lot.

Coarse

Pine bark, pebbles and recycled concrete and bricks make a long lasting mulch which is excellent for preventing weeds. It also cools the  soil but doesn’t add many nutrients, so add some nitrogen rich fertiliser to the soil before spreading the mulch. This sort of mulch can be 5-7cm deep.

Medium

Wood chips are  excellent for reducing weeds. This sort of mulch is usually laid 2.5cm – 5cm deep. Water less frequently so plant roots grow deep into the soil.

Fine

Sawdust and euca can stop water getting into the soil, so don’t make it too thick - about 2.5cm deep. Top it up each year when the ground is starting to dry out. Pea straw, cow and horse manure and compost also make excellent mulches because they improve the soil and attract worms.