Obviously, the water-saving benefits of a Mediterranean landscape are lost if your irrigation system is not used correctly. Tom begins the transformation of our Solana Beach front island with an irrigation lesson for drought-tolerant landscapes.
The existing spray heads in the garden were mostly usable with a few minor changes. Tom added a couple of heads for more complete coverage and fitted all risers with swing joints so they won’t break.
Many people believe that an irrigation system must consist of micro-sprinklers and drippers to be water-wise. This is not true. The concept of drip irrigation was born in the agricultural and nursery industries. While it is an efficient means of delivering water to hundreds of identical plants lined up in rows, the benefits do not necessarily carry over to the home garden.
Looking at Tom’s plan for this island, we find over a hundred individual plants that need watering. Running a drip emitter to each one would be tedious and expensive. The conventional spray heads that Tom uses are much better at watering all the plants in the bed with much less work, and less chance of damage or clogging. Spray heads also deliver water to the plants in a more natural ‘rain-like’ manner, which the plants are naturally adapted to expect.
How you use the conventional spray heads is where the water savings come into play. Tom suggests that you use an irrigation clock that has the option of programming multiple start times (most do). While a landscape may need 15 minutes of water on a particular day, if you only use one start time, much of the water will run off the landscape. If you break those 15 minutes into three five-minute intervals every hour, you give the soil a chance to absorb the first batch of water before giving it some more.
New Mediterranean landscapes will require more water for the first year than at any time in the future. Since the roots have not established a network, they are less able to take advantage of the irrigation. This means that you’ll be giving them more frequent watering to get them started.
If you install a new landscape this fall, be ready to water through the winter during any dry spells, and continue frequent watering through next summer. Come next winter, they’ll be ready to handle a more conservative watering schedule.
A great local web site to help you figure out your particular landscape’s water needs is www.bewaterwise.com. They have a watering index and a watering calculator to guide you towards a more efficient watering schedule.