How To Save Water In Your Organic Garden

Nov. 15, 2009 - PRLog -- Prudent use of water is vital for successful organic gardening. Our blog this week which is also loocated at  http://cityfoodgrowers.com.au/blog-latestposts.php?catid=63 gives you 14 tips on reducing your water usage and at the same time, achieving optimum moisture levels for a healthy garden where you grow your own vegetables, herbs and fruits.

To give you a context for the water saving tips, I will firstly explain how to easily determine the optimum moisture levels in your own garden.

When the soil around your plants is holding as much water as it can without puddling or running off, its particles stick together. This forms a durable, pliable ball that will stick in your hands if you shape it. This soil is said to be at field capacity. The more crumbly the soil, the less water it has and the further it is from field capacity. When the soil around a plant is holding less than 50% of the water it can, then its likely to be below field capacity and need watering.

It is important to test this by not only looking at the surface soil, but also digging down to the root depth of the plant (away from the plant so you don’t disturb its roots). Press some soil from that depth to see if it passes the ball test.

Plant behaviour is also a very good measure. The most obvious plant response is wilting, although this can be misleading, as it depends on the time of day you test and the type of plant. Some plants, such as cucumber, eggplant, lettuce, capsicum and tomatoes wilt in excessive heat whether or not there is adequate moisture in the soil. These plants can recover quickly as the sun sets and the temperature drops. If a plant is still wilting by the evening or the early morning, then water immediately.

The watering needs of plants change as they grow. The plant generally needs more water when: they are young and their roots are close to the surface, when flowering and when fruiting. If the plant does not get sufficient water when needed, it will weaken, become stunted and likely fall prey to pests and diseases. Differing types of plants require more water than others. Our plant attributes search on our web site at www.cityfoodgrowers.com allows you to search plants by water usage: low, medium and high water usage.

In all but emergency cases, such as extreme wilting in the morning, water plants in the late afternoon several hours before sunset. This gives the plant leaves time to dry, otherwise if you water too late and water goes onto the leaves and they are wet overnight, fungi and relate diseases are more likely to set in. Instructional information is provide in our member web site at www.cityfoodgrowers.com on how to deal with diseases and pests if you slip up with watering, but there is no substitute for keeping the plants happy with the right moisture levels.

The question of how often to water is a very important one. If you water too often, then you encourage the roots of the plants to be shallow instead of naturally going deeper for moisture. This also restricts the capacity of the plants to draw nutrients from deeper in the soil and also weakens the plants capacity to withstand changing levels of surface moisture.

When the plant is well established, then watering twice per week should be adequate, however if you are fortunate enough for rain to occur at one of your planned waterings, then it could be once per week. In my own garden, at certain times of the year, I can go 2-3 months without watering because of rain and then at other times when it does not rain for months, my watering becomes regular. Its also helpful to consider the increased likelihood of rain around full moon times. The moon cycle search on our web site at www.cityfoodgrowers.com will tell you the cycles.

Water saving tips

1. Increase the humus levels in your soil - Good humus levels increase the water retention capacity of your soil. Humus can hold up to 6 times more water than dry sand, loam or clay soil. The best way to increase humus levels is to progressively work on the fertility of your soil.

2. Increase organic matter in the soil - Helps with water retention. This includes animal manures, green manures, un-seeded weeds, plant remains which are not diseased and mulch.

3. Add mulch to retain moisture – This holds in moisture and reduces water loss from evaporation. I suggest taking mulch off your garden beds in cooler times (except where you get high levels of frost and snow) to help with natural humus forming processes.

4. Water friendly garden bed design - Raised garden beds tend to hold moisture better, especially if they include good levels of organic matter. Make sure the bed is level and sloping slightly into the middle so that water does not easily drain off the sides. Keep the sides of the bed as vertical as possible. Using bed borders is a big help here, such as, rock, timber (untreated) or metal.

5. Train plants to use less water – By watering less frequently, but more quantity when you water, you will use less water and help the plants roots to go deeper for moisture. Constant watering encourages roots to stay shallow and makes the plants more subject to wilting from changes in surface level moisture.

6. Always prefer rain water – If it has rained or you expect it to rain, create a gap in your watering pattern. Plants will always get more benefit out of rain water compared to any reticulated water, especially if the rain comes near a full moon, which is very common.

7. Water the roots only – Only water the base of the plant, not the leaves. This maximises available water to the root area and minimises potential for mould on leaves

8. Water at the right time – Only water in the late afternoon when the temperature has cooled. Do not water in the middle of the day. This wastes water and may result in burning of the plant leaves.

9. Never use water soluble fertilizers – These are the fertilizers commonly used by industrialised agriculture. They encourage plants to use large volumes of water.

10. Have low water usage systems – For larger gardens, only use a dripper system. Do not use sprinklers as they waste large amounts of water, encourage weeds to grow on paths and wet plant leaves increasing the potential for mould.

11. Focus on soil health – This leads to healthy plants which are more capable of staying healthy with less water

12. Efficient planting layout – By putting plants close together (using distances from the planting guidelines in our Planting calendar), you will find that: (1) foliage will shelter the soil and help to reduce evaporation and (2) more plants can share in the water you use.

13. Use the best quality water you can get – The fresher and cleaner the water you use, the more likely the plants will respond positively, i.e. they get more value out of the water, so you can use less water overall.

14. Grow low water usage plants – You can select plants by water usage in our web site, at www.cityfoodgrowers.com

# # #

Cityfood Growers provides home gardeners with easy access online to localised knowledge on growing their own food with organic gardening methods. Gardening workshops, urban agriculture consulting and food gardening content for schools is also provided.