Malcolm Rands on using water wisely in the garden
The summer of 2013 was one of the hottest on record and even though we’re well into Autumn there is still no rain. In Auckland we’ve had the second driest summer in 50 years and many of parts of the country have been declared official drought zones - bringing home the need to use water sparingly and wisely in our gardens.
What’s the best time of day to water?
I would always recommend watering the garden first thing in the morning - if you water during the day you run the danger of the droplets of water on the plants acting like tiny little magnifying glasses and you can actually burn the plants. So the very best time is early in the morning just at the break of day as the soil is beginning to warm up and the water will warm up with the soil. If you’re not an early riser you can buy a timer and make sure it turns on at the right time of day and also runs for as long as you want it to run. The other time you can water the garden is at the end of the day - you won’t burn the plants because the sun is getting weaker - the down side is that the soil is getting colder and the plants will be getting a bit cold and damp; some people worry that you can encourage moulds by doing this.
How often should we be watering?
What a lot of us love doing is watering the garden ourselves - standing there with the hose admiring our beautiful gardens and that’s o.k but the danger of doing shorter waters is that you encourage the feeding roots up into the very top of the soil. To drought-proof your plants you want to encourage the roots to go very deep into the soil. The way to do that is to do less frequent but much longer waterings - even up to half an hour. If you have an automatic watering system not only do you set it to turn on at the beginning of the day, you can also time it to run for about half an hour each time.
What are some of the ways we can reduce the need to water the garden?
Any organic gardener will always tell you to use mulch, it’s a key part of any organic garden and what we’re doing is we’re using other plant material to cover the earth. In nature you will never find bare soil (unless you’re in the desert!). The trouble with bare soil is that when it rains the water will evaporate straight away and when the wind comes along it’s even worse it’ll actually suck the moisture out of even quite deep soil. The other thing that’s important is that in that top layer of soil is where lots of the life in the soil happens - all the microorganisms, even beneficial fungi and science is still discovering the complexities of these and how they add to plant health. Aside from mulch you could also use drip hoses which you place under the mulch and water will slowly ooze out into the soil or another type of irrigation that sits on top of the mulch which has tiny little sprinkler systems and a third way is something called a leaky hose. You can find these on the internet, they are made from recycled tyres and they sit in the soil itself and the walls are permeable enough that the soil will draw water out of he hose as its needed so you can leave it on all the time and it’ll automatically keep the soil at a moist level. The fourth thing we can look at is using your greywater or the wastewater from your laundry and your shower and you can reuse this on your garden particularly if you’re using good eco products to wash with. I wouldn’t recommend using water from your kitchen (and you’ll need council permission to reuse your household greywater on the garden).
Choosing plants that are naturally drought resistant.
If you’re following the principles of permaculture then what you’ll need to do is find plants that really ‘belong’ in your garden; plants that suit the type of soil you have - whether it’s a rich volcanic soil or a hard clay soil, the type of rainfall you have, the wind, the sun - your plant choice should suit those particular conditions.
And how do we find plants which are best suited to our gardens?
The best way is by asking friends and neighbours and the real gold (if you can do this) is by joining your local garden club. Often these people have been in your area for decades and they’re fanatic gardeners and you’ll often find that certain tomato plant variety that never gets attacked by bugs or fungi and they don’t need as much water and that variety will be particularly suited to the conditions in your garden.
Choose plants which are known to be naturally drought resistant - the classic ones are Mediterranean type herbs like Rosemary with their woody stems love the dry, an example of a NZ plant we’ve got is NZ spinach - (actually an Australian native!) its very much like a succulent - it’s got a juicy leaf and will survive dry times and will grow all year-long here in NZ so it’s a great one to have up your sleeve an extra green to pick.
And one last tip: when we plant our plants close together the roots are competing with each other (for moisture) so space your plants out quite well, keep the mulch up and you wont need to water them nearly as much.