Because the sale price of any given home will be affected by a myriad of factors, it would be impossible to state with precision what the projected dollar value of a given garden renovation might be.
While most (but not all) research carried out by various organisations over the years tends to support the widespread opinion that money spent on the garden can offer a good return on investment, market conditions as well as the quality and style of the garden are going to have a huge influence, of course.
What price koalas?
A study of four suburbs in Redland City has attempted to quantify the effect of koalas and koala habitat on poperty values. The results indicate that if koalas can be seen from a particular property, people will pay an estimated $3100 extra for it. Location in a koala habitat area is also considered advantageous. The report, The presence of koalas in neighbourhoods and property values: a hedonic property values study (PDF), is available at Redland City Council's new Koala Central website, which has a range of news, information and other material for adults and children. (September 2010)
Landscapes appreciated in Texas
A study of homes in Lubbock, Texas, indicated that quality landscapes can have a substantial effect on sale price. Reported by Jeff Gillman here: New Hort Research that Gardeners Can Use - March '09 Roundup. (UPDATE: a copy of the original article is now available in PDF form from the American Nursery & Landscape Association here: Impact of Improved Landscape Quality and Tree Cover on the Price of Single Family Homes)
Landscaping might not recoup spend in a falling RE market
A 2008 UK study indicated that in a falling property market, most home improvements (including landscaping) don't recover the money spent on them. See House Prices: Home improvements are a waste of money (Telegraph Media Group) and Home improvements 'not recommended' MSN Money (UK)
What about lawn?
A survey conducted on behalf of Turf Australia suggested that turf in a front yard increases the perceived value of a home compared to some other "landscape surfaces". Source: The grass is greener when it comes to property values
Front gardens and house prices
According to the Horticultural Trades Association, a survey of UK estate agents suggests: First impressions count: Research from PlantforLife reveals the £5000 benefit of a front garden (March, 2008).
Trees increase Brisbane property values
Research indicated that the top five suburbs in Brisbane (rated by median house price) were all well furnished with street trees. In contrast, some of the poorest performing areas had few trees. Read more at the Real Estate Institute of Queensland (REIQ) website: Trees maketh the street (July 2003)
Britons believe in the value of gardens
A survey on behalf of the UK's Saga insurance indicates that a majority of Britons think the garden is an important feature when house hunting, and believe that garden improvements will result in an increase in house value many times the money spent. Read more at the Saga Insurance website: Green Fingers
Many facets to garden investment
National Savings and Investments (UK) found that while most people spend money on their gardens for the enjoyment of their families or to attract wildlife, many do expect to see a monetary return for their investment. Read more at their website: Brits invest in their garden
UK communities improve property prices
The Britain in Bloom campaign encourages communities to improve their local environment in a variety of ways including landscaping. A study has shown that communities that have entered the competition, especially award winners, have higher house prices than nearby areas. More information from the Royal Horticultural Society HERE
Could a water tank improve your property value?
Archicentre (the Building Advisory Service of the Royal Australian Institute of Architects) suggest that as water restrictions hit many parts of Australia hard, a water tank connected to a drip irrigation will be more likely to attract buyers than some luxuries inside the house. Apart from the landscaping benefits, these systems could also help homeowners control cracking problems resulting from dry soils.
However, Archicentre warn that many homes have roofing problems. Fixing and maintaining roofs and gutters will help maximise water harvesting as well as protecting homes against the weather extremes that may accompany climate change
More on what they have to say about these issues at their website:
Drought To Change Home Buyers Priorities (January 2007)
Climate Change Means More Maintenance For Home Owners (January 2007)
Move or improve?
A poll of Archicentre architects indicates outdoor living additions are becoming popular among Australian renovators (Daylight Saving a Boost to the Outside Room Trend). Archicentre also suggests that homeowners, especially those nearing retirement, will show renewed interest in renovation in an attempt to add value to their homes. More on this theme from Archicentre here: Invest in Your Home, Create Wealth and Enjoy Life and here: Home Owners should have Confidence in Australian Housing Market. (October 2008)
Good gardens reduce crime
A study in Philadelphia has correlated well-maintained vegetation with lower rates of certain crimes such as aggravated assault and and burglary. This could be partly due to the calming effect of greenery on behaviour, and partly due to the strengthened sense of community leading to greater vigilance by residents. Furthermore, the message that people care about their community - and are watching - is communicated with well- maintained gardens and public spaces. Source: Study examines deterrent effect of urban greening on crime (April 2014)