I know the uncertainty of the hose pipe bans has had a big impact on our work and the public's confidence in creating gardens.
I am concerned about the long term implications and the sustainability issues which the uncertainty and also the policies (exemptions) themselves lead to. I can already see that the issue of keeping new plantings alive will put people off planting and this represents a significant threat to our green environment and to our businesses. Then there are the inevitable environmental implications of reduced planting with more paving leading to worse flash floods etc. Or, we will see a big increase in the use of plastic and computer gadgets which make up the irrigation systems which we are being encouraged to install. I don't believe that this is good for the environment either.
I've written to the water boards in my area and no one seems to have any figures to substantiate the decision to promote irrigation system's. Do we really know that water use is less with a drip system over say 5 years compared with watering with a hose in the evening for the just first year in dry periods only? Personally I'd like to see the facts and figures before I throw myself into filling my clients' gardens with plastic and computers. It not just the plastic and cost that I object to, but also the long term waste of water that irrigation systems will surely create. I am sure that most of my clients will keep their irrigation system running for years rather than risk letting plants stand on their own root system.
I am sure that I am not the only garden designer who finds that with careful plant choice, good soil preparation (with plenty of organic matter added) and a good mulch, new planting does not need artificial irrigation beyond the first year of planting. After the first year the right garden plants, planted properly, can remain and flourish without artificial irrigation. The water boards seem to be assuming that watering has to take place long term in gardens and therefore we must have drip systems rather than hoses. My concern is that the water industry is being informed by the people who sell irrigation systems and not by professional garden designers who are trying to be sustainable and take care of the environment.
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The most water efficient irrigation system is the drip line- this applies a slow but steady stream of water precisely to the point where it is needed, around the rootball of the plant.
The amount of water given to the plants is governed by how long the system is on; for example if each drip gives off two litres of water an hour but you only want to give the plants 1/4 of a litre of water each you only run the system for 15 minutes. Likewise if you have a plant with a bigger rootsystem (a tree, let's say) you might calculate that it needs four litres of water per day, so would put in two drip heads to feed into the root system.
Compare this with a 'leaky hose' which waters all along it's length or a sprinkler which waters leaves, paths etc. the drip system is a far less wasteful way to irrigate.
By far the best way to care for newly planted plants is for someone to go out twice a week and give each plant a really good soak, giving the plant the water it needs to get established but encouraging the root system to go down and find it's own moisture. If your customer can do that competantly themselves, or afford to hire someone to do it all summer if/when required then that's great. If, however, they are not competant at watering or don't want someone in to water for them then a drip irrigation system might be preferred. Giving them the options and explaining that the drip system is actually only really needed in a new planting scheme for the first year (and may not reach plants they choose to add at a later date) is the best you can do. Likewise telling people not to run their irrigation when there's been several inches of rain may or may not be taken up as advice.
Great to have a conscience, but unfortunately all we can do is give the customers the options clearly and concisely and hope they themselves are wise enough to make the right decision. After all if someone wants you to install an irrigation system when they know it will only be used for a few months it is, at least, their choice and their money they're wasting...
Dear Sellina, reading your post I hope I can give you few bits that will assist. for theones that donot know me Ill say I was a garden designer for 8-9 years in israel and 2 years after in the UK . I am agronomist in my degree and was lucky to study in a small faculty from many clever people thatI learnedwith the years what massive infulunce they hadon ho horticulture worldwide.
Just like yourself my concern was always ,environment and long term impact.
I was tought that dripp irrigation had massive reserch /I think it was on the late 70es early 80es. It is alot about the movement of water in the soil. And HERE is the important bit to learn
as it was said before it drip the water slowly into the ground ( normaly 2litre per hour but can get even more than that , the water movingdown in the ground but also spread creating a big onion shape , called in professional lang as the watering onion.
What it means that large area that supplied with water , the surface above it yet dry. So these water do not evaporate. ( in normal watering massive amount of the water just evaporate) Have you ever noticed an area with no plants get dry after few days and if you lift a big stone it is still wet under.
As a designer you can find that if you planned well all your plants will grow well. I used to plant many small plants yet give a guarantee for success. Nearly never happendthat Ihad to replace a plant , While talking on over 20,000 plants a year.
It is also comfortable to the house owner when it is all automated.
It is important to know that theory as , many times you found customers sayingthat theirrigation does not work well and does not supply enough water and infact all the water spread under the surface.
With regards comments here ,it is very true and worth considering to supply a bit more water and space the frequency so the water will go deeper and so as the plants roots.
Like yourself I think it is far more important to choose plants that can grow well, without extra watering in just few years. Hope it can assist
Hi Selina
I agree with you that water management in landscaping can become over dominated by costly technology and what you express about applying the basics of soil management and plant selection to achieve a rain-fed system is entirely correct and worthwhile.
For situations where irrigation is necessary, due to restricted roots or a plant requirement for example, there is plenty of independent evidence that drip irrigation, when used correctly, provides many benefits such as greater efficiency and convenience (eg http://www.ext.colostate.edu/pubs/garden/04702.html) . Part of the problem is lack of knowledge of moisture conditions in the root profile, such that most people relying on their own judgement get it wrong and tend to over- irrigate.
I am one of the guilty parties developing better and more cost effective electronic systems for monitoring soil moisture and linking it to the internet and powerful computer programs to enable the correct amount and timing of irrigation to be applied (www.soil-moisture.co.uk) . These systems are mainly applied to agricultural production but in recent years I have also become interested in some aspects of urban landscapes where I think there is a strong case for improvement.
In particular, I am very interested in the possibilities for enhancing the city environment with planting systems attached to roofs and both interior and exterior walls. I started looking at these systems over a year ago as a potential application for our electronic sensors but concluded that there was too much variability in moisture distribution to enable a cost-effective sensor-controlled irrigation system.
Consequently I looked at better ways of delivering water as required by each plant and even using water stress to control the plant growth so as to reduce the pruning requirement. The resulting system (which I hope to make it available for sale when perfected) seems to be so effective that it doesn't in fact require use of our sensor technology.
The impression I hope to give is that technology can be worthwhile and that people involved in it are generally trying to make life better, more efficient and environmentally friendly.
with kind regards
Terry McBurney
Let's hope there's not a knee-jerk reaction to this hot weather and talk of a hosepipe ban is kept to a minimum.
However it's worth just reminding ourselves of our collective responsibilities to give good advice to clients as well as set a good example when it comes to hosepipe and water use in general.
I installed my own basic drip irrigation system last year during the hosepipe ban, mainly because i had put lots of new plants in and didnt want to spend hours with a watering can. In hot dry periods i run it once, maybe twice a week for 1 to 1 1/2 hours and it works an absolute treat. The plants are healthy, i only need to give extra water to those plants not served by the pipework and those in pots. But so far this year i havnt had the hose out once! Ive found that those plants not directly served by a dripper but within approx 12 inches of it seem to benefit just as well, assuming they are not freshly planted and hence shallow rooted.