Resources Down the Drain
Published in the Toronto Star – January 21, 2017
Late in January is not exactly the height of the gardening season, but for this: it is the best time of year to dream about the gardening season ahead of you. It seems that many of us urban dwellers have been dreaming about where to park the car. As a result, a record number of us are exploring the option of paving over the front yard to make room for our personal transportation, without a lot of thought given to the bigger picture.
The City of Toronto has by-laws with detailed rules for creating a front yard parking pad. It is a long process and very few home-owners are successful in gaining a permit to pave over their front yard. In Great Britain, a study indicates that ripping out the garden in favour of paving and other hard surfaces is wreaking havoc on their storm water sewer system.
Lauriane Suyin Chalmin-Pui, PhD student, Landscape Department, University of Sheffield, has created a report that indicates that there are 5 million front gardens in the UK with no plants growing in them (1 in 3) and 4.5 million are paved over (1 in 4).
While no statistics are available about the Canadian urban experience in this regard, all you must do is drive down any residential street in Toronto and you will see for yourself that this is not a problem unique to the UK.
The UK has created a formal response to this with a program sponsored by the Royal Horticultural Society called ‘Greening Grey Britain’ and I think it is incredibly smart.
What problem?
When we pave over our front yard, we impact on the greater environment:
- Creating a heat island. When vegetation is lost on a street and replaced with hard surfaces, they absorb heat in the day and release it at night, making it hotter. Air conditioners work harder and are used more often.
- Flooding. A higher risk of flooding occurs when we eliminate green spaces and replace them with hard surfaces. Storm water run-off can be 50% greater on the hard surface area during a summer storm. The risk is an over-worked storm water system and potential flooding.
- Loss of pollinators. Replace flowering plants with hard surfaces and watch the hummingbirds, butterflies and song birds disappear from the neighbourhood. Is this the ‘canary in the coal mine’?
- Dehydration of street trees. Many of our well-established streets in Toronto are lined with priceless, mature trees that rely on moisture at their root zone to live. Their root zones can extend beneath the curb and sidewalk into your front yard. Remove a permeable green surface and replace it with asphalt and the results can be devastating for street trees that are already stressed by the urban environment.
What can you do?
If you are successful in gaining a permit to create a parking pad in your front yard, you will most likely be restricted to using permeable paving option. These are just a few options available:
- Permeable paving. Matrix pavers are sometimes called ‘cellular paving’. They are hexagonal cells made from recycled plastic and hold an aggregate of your choice. Lay according to the manufacturers instructions so that rain water drains freely away and through the bricks.
- Grass reinforcement. There are many products that can be used to support the growth of grass on a parking surface. Yes, it is possible to park a car on a lawn! Look for honey-comb plastic cells, much like the matrix pavers described above but with larger holes. Sow grass seed directly into the cells and water as you would a normal lawn. The grass will die where the tires of your car frequently drive over it but will thrive elsewhere. In any case, rainwater will flow through it.
- Brick pavers. Ask your landscape contractor or visit a local building supply outlet to look over various options of pavers that allow water to run through, without creating a solid, impermeable surface. Details about contractors at www.landscsapeontario.com.
If you have decided that you want to apply for a permit to park a car at the front of your house, you can minimize the impact by using:
- Vertical growth. Consider planting hedges and vines in your front yard to reduce the negative effects of hard surfaces. They are green, produce oxygen and can provide nesting places for birds. Some flowering vines are quite colourful.
- There are many smaller trees that will provide a green canopy without taking up a big ‘foot print’ in the front yard. Some of my favourites are Japanese tree Lilac ‘Ivory Silk’, flowering pear ‘Chanticleer’ and the native Downy Serviceberry. Avoid crab-apples and other fruiting trees as they will drop fruit and other sticky stuff on your car.
- Consider the many options to plant in cramped and small spaces using containers. Flowering plants, evergreens and even vegetables can thrive at your front door or next to a wall.
Perhaps with some planning and consideration for the environment and pollinating neighbours, a healthy compromise can be struck between parking the car and enjoying a cool, green front yard. You will find valuable information about ‘front yard parking pads’ on the City of Toronto website. It is a great resource. www.toronto.ca
Details about Greening Grey Britain at www.rhs.org.uk/ggb.
