Our District

Waterwise irrigation

SUPER EFFICIENT, SUPER CONVENIENT

Who wants to spend all summer standing on the end of a hose? Free yourself with low-tech, low-cost irrigation set-ups that see your garden through the dry times.

The trick to these watering hacks is delivering water slowly, so it sinks deeply into the soil instead of evaporating, crusting or running off. These systems can be used with a hose or watering can, or attached to a tap timer for full automation, or joined to a reservoir (such as a barrel, filled either with rainwater or tap water) that slowly empties over several days.

Spraying water around the leaves and topsoil encourages fungal diseases and creates shallow-rooted, needy plants. A deep weekly water, instead, encourages deep-rooted, resilient plants - better for your plants, your time and your water bill. It's also a more efficient use of water, putting less stress on infrastructure and on our local rivers and streams.

Some low-cost, low-tech irrigation options:

BOTTLE-WICK

Great for indoor or outdoor container plants. Read more

CLAY POTS OR OLLAS

Used for thousands of years, these only need topping up once a week or so. Read more

SEEP HOSES/ROPE WICKS 

Inexpensive and easy to install, these run off either mains or barrel pressure. Read more

DEEP PIPES

Vertical pipes buried next to trees at planting time encourage deep-rooted, resilient plants. Read more

RAIN TANKS

Store water for when it's needed. Read more

GREYWATER 

Recycle water from the bath, shower and laundry so every time you wash, you're also watering the garden. Read more

RAINGARDENS/SWALES 

Sculpt the earth into contours that slow down rainwater and hold it for plants to use. Read more

Work out which parts of your garden you want to water, then make simple, slow-release systems that can run off a tap or a reservoir.

RESERVOIRS

A reservoir could be a barrel, bucket or any large container. Attach these to a slow-release system (see opposite) and refill the reservoir every week or so.

ZONE YOUR GARDEN

Targeted watering is easier, cheaper and quicker.

  • Group together plants with similar water needs.
  • Vegetables and fruit trees need water – concentrate irrigation on these.
  • For ornamental areas, there are many shrubs and perennials that can survive on rainfall only. Read more

WATER ON FRIDAYS

This always seems to be a strange piece of advice, but a lot of our water supply issues are caused by the summer peaks in usage. If you look at Kāpiti’s daily water use on a graph there are huge spikes on summer weekends, especially when it’s sunny and thousands of people all decide it would be a good day to wash the car, house or boat, or water the garden.

Our water infrastructure, an expensive system of pipes and pumps, has to cope with these dramatic peaks - even though that capacity might not be needed the other 90% of the year. So knocking the peaks off the water usage graphs is great news for ratepayers.

A deep watering on Fridays should see your plants through the weekend. Take your time over each area - watering deeply once a week is better for your plants than a shallow sprinkle. This is where a tap timer can come in handy. Attach a seep hose on low flow, set the timer for a half-hour or so and walk away.

IRRIGATION EXPERIMENTS

Since 2016 we’ve been trialling some of these low-cost, low-tech irrigation systems in community gardens. What we’ve learned so far:

  • Clay pots work brilliantly: Everyone who tries this method finds it works really, really well. The self-filling system installed at Matai Rd, where the pots are filled by plastic piping and mini-dripheads running off a barrel, is probably not worth it unless you have a large commercial type operation; the more bits of plastic you use, the more there is that can go wrong. The clay pots on the other hand keep working year after year, and it’s really not such a big job to fill them up by hand once or twice a week. Sometimes low-tech and simple is best!
  • Gravity makes a big difference to barrel-driven systems. Even raising your barrel by a metre or so pushes the water through the seep hose much better.
  • Rope seems to work as well as seep-hose when used in a gravity-driven system. This one was a surprise result,  still under investigation so watch this space…

These low-tech, low-cost irrigation options work well on low pressure eg. from a rain tank barrel. These ideas come from David Bainbridge’s fantastic handbook Gardening With Less Water available at Kāpiti libraries.

 

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