A new web guide will help straighten your irrigation

MELBOURNE has begun 2011 with record rainfall, but there’s no guarantee that the lush times will continue. The Bureau of Meteorology predicts that the La Niña conditions that brought the big wet will dissipate by wintertime.

By historical terms, the city’s dams are still low, and stage two water restrictions will remain at least until spring. That means householders still aren’t allowed to water their lawns from the mains. Gardens, however, can be watered by hand at any time, or every second day, at specified times, with manual and automatic irrigation systems. (You can find the full details about stage two restrictions on the Melbourne Water website.)

Geoff Connellan, from the University of Melbourne’s School of Land and Environment, says that just because we can water more often, doesn’t mean we should.

“The most common mistake people make in their gardens is to over-water, because they don’t understand how much water different plants need and how much moisture can be stored in the soil,” he says.

Together with Dr Jon Pearce and a team from the university, Mr Connellan has spent five years developing a free, online tool, called Smart Garden Watering, which helps you understand how to give your garden the right amount of water at the right time.

Using the website, you can calculate your water needs by entering all the details of your garden, including the location, size, slope and soil conditions, as well as the watering method and the types of plants and mulch.

The program draws on localised climate data and soil conditions, together with a database called the Burnley Plant Directory, which comprises over 1500 Australian and exotic plants.

Because it requires such detailed local data, the system is only available to residents in Melbourne and Geelong – for now, at least. “It does calculations for your postcode,” Mr Connellan says. “That’s important, because if you think of a garden in Sunbury and a garden in Olinda, they’re two totally different scenarios.”

The site is sprinkled with facts and features. It includes a Facebook application as well as maps, photos and forums that allow users to see other people’s gardens in their area, contact the gardeners and learn from each other’s experiences.

You can also plug in the details of your water tanks and see their likely storage levels throughout the year, based on the irrigation needs of the garden.

The results can be used not only to help you better understand your plants, but also to see what would happen if you re-designed your backyard. The website is interactive – you can toy with the settings and see how they affect your water consumption.

“It’s a sophisticated tool, but we’ve found that once people have become used to it, they are happy to play around with the options,” Mr Connellan says. “For example, if you choose drip irrigation or spray irrigation, or mulch or no mulch, you can see the consumption changing.

“That’s a very powerful graphical tool for a user. It encourages people to select efficient irrigation methods, and plants with low water needs.”

As a general tip, Mr Connellan recommends drip irrigation systems, underneath a layer of mulch of between 50 and 75 millimetres.

“Most people with plumbed watering systems can save about a third of the water they’re using, if they water wisely.”

Read this article at The Age online

To find the right solar panel, you can’t beat thorough research

THE rebate for residential solar panels has changed, yet again. From the start of July, the cash back available from the federal government will be cut by between $2000 and $2500.

Solar retailers and installers are experiencing a rush of demand before the fall. Many are already booked up until the new financial year, and those that aren’t yet are warning customers to get in quickly.

So if you’re considering purchasing a solar photovoltaic system, it’s worthwhile investigating your options now. But if you miss the deadline, all is not lost – prices may not rise too much.

The federal rebate is based on the trading value of ‘small-scale technology certificates’ (formerly known as RECs), which are created when solar hot water and solar electricity systems are installed. Presently, householders receive a credit of five times the certificate price, but the recent glut of installations has meant that the price – and therefore, the rebate – is lower than usual.

The multiplier will be cut to three from mid-year, and progressively reduced until 2013.

Russell Marsh, policy director at the Clean Energy Council, says the strong Australian dollar and falling costs in the industry mean that despite a smaller rebate, the price of a system won’t increase significantly in the second half of the year.

“Costs are coming down quicker than most people expected. The market is booming – there could be nearly 300,000 houses with systems on their roofs before the end of this year. We suspect [the rebate change] will have a small impact on price,” he says.

Mr Marsh says a good quality, 1.5-kilowatt system will set you back about $4000, out of pocket, depending on installation costs. For an average household, the payback period is around seven years.

If your head isn’t spinning already, you also need to consider the state rebates, known as ‘feed-in tariffs’. In Victoria, power retailers credit panel-owners 60 cents per kilowatt-hour for any surplus energy they feed into the grid (for the next fifteen years).

But new owners may soon miss out. “That premium tariff has a limit and we expect it to be reached within the next six months, or sooner,” Mr Marsh says.

Of course, there’s much more to consider than prices and rebates. To help, the Clean Energy Council has produced a detailed guide to buying solar panels. It covers basic information about the technology and its suitability for your home, together with a checklist for installation and comprehensive lists of questions to ask retailers and tradespeople.

For even more information, try the articles and podcasts put together by Choice.

Ingrid Just, from the consumer advocate, says a 1.5-kilowatt system produces about a third of the energy used by an average household.

“Firstly, get into the habit of reducing your energy consumption,” she says. “Australians tend to use a lot of electricity, so you should look at how much panel capacity you actually need.”

Before you buy anything, be sure to research thoroughly: ask your energy retailer about the tariffs it offers panel-owners and get quotes from a number of retailers and installers.

“Make sure you’re using an accredited installer and that any panel you consider meets Australian Standards,” she says. “Look for a warranty of 25 years from a company you trust.”

Read this article at The Age online

A mix of ingredients will put your compost on the top of the heap

GARDENING guru and landscape architect Costa Georgiadis can’t get enough vegie scraps. To feed his chooks and worms, and his compost pile, he imports peelings from neighbours.

“I’ve got a bin at the front and another one on the side street and my neighbours drop their scraps in them,” he says. “It’s a wonderful resource and everyone has it.”

Today marks the start of International Composting Awareness Week. To celebrate, Cultivating Community and Yarra City Council are holding a ‘Composter’s Composium’ next Saturday, May 7, at Smith Reserve in Fitzroy, from 11 am. The event will be a humus-inducing extravaganza, complete with live music, a workshop by Mr Georgiadis and (nearly) every kind of composting contraption known to urban living.

Lisa Coffa, senior waste officer at the council, says organic waste still comprises over half the kerbside collection, by weight. “It imposes great demands on our infrastructure and requires a lot of resources to pick up,” she says.

But that’s not all – every tonne of green waste in landfill causes about a tonne of greenhouse gas emissions. Ms Coffa says composting is a low cost, low-tech, local solution. Most councils, including Yarra, offer residents a discount on worm farms and bins, as well as advice on how to do it right.

“For most people, it’s very easy to convert green waste into something productive,” she says. “If you’re composting, you are better connected to your food source. It makes the link between what you purchase and what you throw away.”

For his part, Mr Georgiadis likens composting to cooking. “When you make compost, you transform the ingredients into something edible, with the help of microbes and worms and plants. You’re actually a chef, cooking your own chemical-free elixir.”

His first tip is to prepare well. “Compost gets a bad wrap when people do it half-heartedly,” he says. “You need to have the ingredients on hand, otherwise you’ll end up with a lasagne that only has pasta in it – and then it will become a seething, smelly, gooey mess.”

In the kitchen, get yourself a sealable container to stop vinegar flies from invading. In the garden, choose a shady spot and set up dedicated, covered spaces for several materials. You’ll need to mix the nitrogen-rich kitchen scraps with carbon-rich brown stuff, such as dried leaves, straw, shredded paper and cardboard.

Other items on Mr Georgiadis’ recipe include manure, green garden clippings, rock minerals and soil. Make sure you’ve also got a watering can handy and a corkscrew-style aerator (about $20) or garden fork for turning the heap.

“The key to any composting system is diversity, so every time you add something, add some of the other elements as well. Water it, turn it, cover it and let it do its thing,” he says.

Once the bin is full, you’ll need to leave it for about two months (but keep turning it every week) while you start a second batch.

When it’s done, to test if your mix is right, Mr Georgiadis suggests grabbing a handful. “If you squeeze firmly, you should see a little liquid running along the bottom of your pinky. If a whole lot of juice comes out, you need more carbon material; if nothing comes out, you need more water.”

Read this article at The Age online