Wednesday, June 20, 2012

Friday, June 15, 2012

Water-Saving Tips for Your Lawn and Garden

In the summer months, municipal water use doubles. This is the season when Canadians are outdoors watering lawns and gardens, filling swimming pools and washing cars. Summer peak demand places stress on municipal water systems and increases costs for tax payers and water users. As water supplies diminish during periods of low rainfall, some municipalities must declare restrictions on lawn and garden watering. By applying some handy tips, your lawn and garden can cope with drought conditions and you can minimize water wastage.

General Tips

Much of the summer peak demand is attributed to lawn and garden watering. Often water is applied inefficiently, resulting in significant wastage due to over watering, evaporation or run-off. Here are some general watering tips to help avoid wastage:
  • Before watering, always take into account the amount of water Mother Nature has supplied to your lawn or garden in the preceding week. Leave a measuring container in the yard to help you monitor the amount of rainfall (empty it once per week) and follow the tips below to help determine how much water to add. Also bear in mind any watering restrictions that may apply in your municipality.
  • Water in the early morning, before 9 a.m., to reduce evaporation and scorching of leaves from the sun. Water on calm days to prevent wind drift and evaporation.
  • Set up your sprinkler or hose to avoid watering hard surfaces such as driveways and patios. If you're not careful, it's water and money down the drain.
  • Water slowly to avoid run-off and to ensure the soil absorbs the water.
  • Regularly check your hose or irrigation equipment for leaks or blockages.
  • Collect rainwater from your roof in a rain barrel or other large container and keep it covered with an insect screen. Direct the down spout of your eavestroughs into the rain barrel.
  • Choose an efficient irrigation system. A soaker hose placed at the base of plants on the ground applies water to the soil where it is needed — rather than to the leaves — and reduces evaporation. Drip or trickle irrigation systems are highly efficient because they deliver water slowly and directly to the roots under the soil surface. This promotes deeper roots, which improve a plant's drought resiliency. If you use a sprinkler, choose one with a timer and that sprays close to the ground.

Tips for Your Lawn
Established lawns1 generally require about 2.5 cm (1 in.) of water per week to thrive.2 If Mother Nature is providing this amount of rainfall, your lawn will thrive without supplemental watering. When rainfall does not provide adequate moisture, your grass may start to turn brown. This does not mean it is dead — it's simply dormant. An established lawn will recover and resume its green appearance shortly after sufficient rainfall returns.
Apply these tips to save water and money without compromising the health of your lawn:
  • Apply about 2.5 cm (1 in.) of water not more than once per week and skip a week after a good rain. The correct amount can be estimated by placing an empty tuna can on your lawn as you apply water evenly across the surface. When the water level reaches the top of the can, you've applied about 2.5 cm (1 in.) of water which is all your lawn needs. You can time how long it takes to reach this level, then set the timer on your sprinkler.
  • Water thoroughly. Deep watering at this rate is better than frequent, shallow watering because it encourages deep roots.
  • Don't water your lawn excessively. When it's waterlogged, it may turn yellow and develop fungus and diseases. Oxygen and mineral uptake may be restricted on heavy clay soils. Too much watering can also lead to thatch and fertilizer leaching.
  • Check with your municipality to see if watering restrictions are in effect.
  • Avoid mowing and unnecessary traffic on your lawn when the lawn is dry or dormant.
  • Don't cut your lawn too short. Set the blade on your lawn mower to cut no lower than 6 to 8 cm (2.5 to 3 in.) so that the roots are shaded and better able to hold water.
  • Aerate your lawn once a year in the early spring or fall to improve water penetration. Afterwards, top-dress by applying a thin layer (max. 15 mm — 0.6 in.) of organic material and rake to distribute evenly. You can overseed after this to help thicken the lawn.
  • A thick, vigorous lawn is the best prevention against weed invasions and can better withstand heat and dryness. A healthy lawn needs nutrients, such as nitrogen. Application rates, sources and timing will depend on many factors including soil type. As a rule, a healthy lawn with good soil needs about ½ kg (1 lb.) of nitrogen per 100 sq. m. (1,075 sq. ft.) of lawn area every year. Leave grass clippings on the lawn to return nitrogen to the lawn, and reduce moisture loss.
1 Newly seeded or sodded lawns have greater water demands.
2 Actual water requirements depend on individual conditions, such as soil type.

Tips for Trees, Shrubs and Flower Gardens
Here are some water-saving tips for trees, shrubs and flower gardens:
  • Direct water to the root system. In the case of trees and shrubs, the roots that take up the most water are generally located within the top 30 cm (12 in.) of the soil and near and even beyond the drip line. This is the area directly below the outer tips of the branches.
  • Plants have different watering requirements at various stages of their growth. Keep soil moist in the first growing season. One rule of thumb is to water trees with a one-hour trickle using a soaker hose at least once per week, barring a good rainfall and more frequently during hot weather. Taper off watering in the fall. In the second growing season, water twice per month in late spring and summer. Once established, trees that are well-selected should require little or no watering other than that provided by rainfall, but ensure they get adequate watering during periods of low rainfall or drought. Actual water needs depend on factors like soil type and species.
  • Water perennials and vines well in the first growing season after planting. One rule of thumb is to water with a one-hour trickle at least once per week using a soaker hose for the first three weeks, barring a good rainfall, and subsequently during hot dry weather. Afterwards, perennials selected to match site conditions should need little or no supplemental watering. If you notice wilting or browning on your perennials, water to a depth of 10 to 20 cm (4 to 8 in.) to help restore the plant's turgidity and vigour.
  • Apply a layer of mulch about 5 to 7.5 cm (2 to 3 in.) deep over the soil surface of the garden to retain moisture, moderate soil temperature, control erosion and suppress weeds. Wood chips, bark and crushed rock are just a few of the materials that can be used as mulch.
  • Use a soaker hose placed at the base of plants, rather than using a sprinkler. This will help to apply water to the soil and roots — rather than the leaves — and reduce evaporation
  • Grass under your tree competes with the tree's roots for water. Remove the lawn and apply mulch instead which helps to retain water.

Designing a Water-Efficient Garden

You can create a lush, colourful garden, like the one in Figure 2, that requires little maintenance or water by applying the seven principles of xeriscaping — an approach to designing landscapes so that their water requirements correspond to local climatic conditions. While these are sound principals for any garden, they are particularly useful if you live in a region with low rainfall or that experiences water shortages.
1 — Design for your site and your needs
Sketch your lot including property lines, buildings, driveways and features that will remain. Add trees, shrub and flower beds, lawn areas, patios, decks, etc.Consider the specific conditions of your yard, taking into account that water requirements will differ in shady versus sunny spots, and slopes versus flat areas or depressions. Moisture availability for your plants will also differ according to your soil type. Sandy soils drain water whereas clay soils hold water. Some places, such as narrow side yards, may be hard to water.

2 — Group plants with similar water needs to make watering more efficient
Shrubs and perennials should be grouped together in mulched beds. Trees should also be clustered in mulched beds rather than isolating individual specimens in lawn areas. This will help to reduce moisture loss and competition.

3 — Amend the soil
First, find out what type of soil you have and improve its water retention capabilities accordingly, for example, by adding compost or other organic materials.
4 — Size your lawn area to meet your practical needs for play and traffic

Avoid many small or narrow lawn areas in favour of a consolidated lawn, to make them easier and more efficient to water. For primarily visual areas, consider water-efficient ground covers, perennials or shrubs. For foot-traffic routes or narrow spots, such as side yards, a permeable inert surface such as wood chips or natural stone requires no water.

5 — Choose plants that are well suited to your climate and site conditions

Consult your local garden centre or the references at the end of this article to find plant lists. Know your site including its soil types. In shady areas, use shade-tolerant species or consider a woodland shade garden. In sunny spots, use drought tolerant, sun-loving species or consider a wildflower meadow. Drought tolerant species should be used on rapidly-draining slopes (avoid turf grass), but you can consider moisture-loving plants in depressions or low spots. For a water-saving lawn, choose a species best suited to rainfall levels in your region. Low-maintenance lawn seed mixes are commercially available. Check your local seed companies or garden centre.
6 — Use mulch
7 — Use an efficient irrigation system and appropriate maintenance

Other Outdoor Activities
Lawn and garden watering is not the only outdoor activity contributing to summer peak demand. You can lower your water bill and relieve the burden on municipal water supplies by doing the following:
  • Use a broom instead of water to remove debris from paved surfaces such as driveways.
  • Use a bucket and sponge to wash and rinse your car, instead of a hose.
  • Cover swimming pools when they are not in use to reduce evaporation.

Shifting Regional Demand Produces Similar Results

The British Columbia Real Estate Association (BCREA) reports that the dollar volume of homes sold through the Multiple Listing Service® (MLS®) in BC declined 14.5 per cent to $4.0 billion in May compared to the same month last year. A total of 7,715 MLS® residential unit sales were recorded over the same period, down 1.8 per cent from May 2011. The average MLS® residential price was $519,923, 12.9 per cent lower than a year ago.
"BC home sales were back on track in April and May compared with last year’s performance, after falling short of the unusually strong first quarter of 2011,” said Cameron Muir, BCREA Chief Economist."
"Recovery of the BC Interior housing markets continued unabated in May,” noted Muir. “Despite a nearly 16 per cent dip in home sales in Vancouver, provincial totals were down just 2 per cent from levels a year ago."
Year-to-date, BC residential sales dollar volume declined 15.5 per cent to $17 billion, compared to the same period last year. Residential unit sales dipped 7.9 per cent to 31,497 units, while the average MLS® residential price was 8.3 per cent lower at $540,270.

Copyright BCREA reprinted with permission

Wednesday, June 6, 2012

Rain Gardens: Improve Stormwater Management in Your Yard

Stormwater refers to rain and melted snow and ice. Stormwater runoff from your roof, driveway and other hard surfaces in your yard is typically directed towards the street and into the municipal storm sewer system. This stormwater runoff, which has picked up harmful substances such as road salt, heavy metals and oils, ends up in streams, lakes or other water bodies, where it can harm water quality and aquatic habitat. Meanwhile, water used for lawns and gardens is drawn from the local drinking water supply.

There are several ways that you can reduce runoff and better use stormwater in your yard while ensuring proper drainage. One relatively easy and attractive method is a rain garden.
A rain garden is a planted or stone-covered bed specifically designed to receive stormwater and allow it to be slowly absorbed into the soil (infiltration). This About Your House provides information on designing and building a rain garden, as well as tips for improving stormwater management in your yard.

Let Nature Inspire You

In the natural hydrologic cycle, stormwater slowly infiltrates into the soil. There, it is naturally filtered and cleansed of some pollutants, is used by plants and replenishes the water table. Stormwater also falls directly into water bodies or gradually reaches them over land or through the shallow water table.
In contrast, stormwater runoff in settled areas usually flows quickly from hard surfaces, such as roofs and driveways, into sewers that eventually empty into water bodies. The increased volume and frequency of high flows can cause erosion and related sedimentation in receiving lakes and rivers. Along the way, the water also picks up polluting substances, such as de-icing salt, grease, oil, animal wastes, excess sediments, pesticides and fertilizers. In areas with combined storm and sanitary sewers, the system can sometimes become overloaded, so that untreated sanitary sewage overflows into natural water bodies. All of these factors can harm water quality, habitat for aquatic species and the stability of shorelines and riverbanks. They also increase municipal costs to convey and treat stormwater.
There is a growing trend towards designing municipal stormwater systems to work with natural processes. These systems involve the use of wetlands and other methods that allow water to soak into the ground, filter pollutants and slow the flow of water before it enters water bodies.
Rain gardens are one way that you can reduce runoff and let stormwater soak slowly into the ground in your home landscape, just as it does in nature. Rain gardens are shallow depressions or low-lying areas that are designed to capture and absorb stormwater fairly quickly and dry out between rainfalls. When planted, they can also provide habitat for birds, butterflies and other fauna.
Steps in Designing a Rain Garden

Rain gardens are relatively easy and inexpensive to design and build, but there are a few considerations to ensure that they function effectively. The two most critical technical considerations are:
  1. Water must infiltrate and not stand in the bed for more than two days.
  2. Water should not create drainage problems on your property or neighbouring ones.

Beyond that, rain gardens can be naturalistic or more manicured, can include a variety of plants, and can be in various shapes.

Find a Suitable Location

Observe the drainage area and paths along which stormwater naturally runs in your yard. Place the rain garden at a low point or at a location somewhere along the natural flow path. If your yard is relatively flat and evenly drained, you can create a depression anywhere, following the guidelines below.

To ensure that water will not simply run over the lower edge, rain gardens need to be as level as possible. If possible, avoid slopes greater than 12 per cent, as they will make it more difficult to create a level garden. If you have no other choice, you can cut and fill a steeper area, as described in the “How to Install a Rain Garden” section, but you will need to ensure that the sides are adequately stabilized.

How to Measure a Slope

Slope is the ratio of the length of the rise (the vertical change) to the length of the run (the horizontal change). Here is a simple way to measure slope:

  • Place a carpenter’s level on a 2 x 4 wooden board situated on the ground along the slope you want to measure and lift the lower end until the board is level (see Figure 3).
  • To determine the rise, measure the distance from the ground to the bottom edge of the board at the end of the slope.
  • The run is the length of the board from the end to where you measured the rise.
  • Divide the rise by the run to obtain the per cent of the slope. For example, if the rise is 5 cm and the run is 2.5 m the slope is 0.05 m ÷ 2.5 m = 2%.
To avoid creating moisture problems, you will need to direct stormwater away from vulnerable areas, such as your house foundation, septic beds or neighbouring homes. Place your rain garden at least 4 m (13 ft.) away from such areas. Also avoid placing rain gardens over underground utility pipes or wires.

Drain Water Away From Your House

Ensure that stormwater is directed away from your house foundation. Follow the tips in Chapter 4 of CMHC’s Landscape Guide for Canadian Homes. The Guide also describes drainage considerations around your main activity areas and neighbouring properties.

Rain gardens do not work well on clay soil because drainage in clay is slow. Look for a spot with soil that is sandy, gravelly, loam or a mix that can include up to 10 per cent clay. If your soil has a higher clay percentage, you can add sand, fine gravel and/or organic matter to improve permeability.

Compacted soils are also relatively impermeable, so you will need to loosen them before building a rain garden. Ensure that the soil is permeable to a depth of between 0.6 – 1.2 m (2 – 4 ft.) below the rain garden. Refer to "Get to Know Your Soil" in CMHC’s About Your House series for tips on analyzing and amending your soil.

The surface of the depression should be at least 1 m (3 ft. 3 in.) above the seasonally high shallow groundwater table. To determine where the shallow water table is, in dry weather dig a small test pit and see if it fills with water. Or, you can ask if your municipality has information about your neighbourhood’s shallow water table. If the shallow water table is close to the surface, find a location on higher ground or abandon the idea of a rain garden.

Along with catching water from other areas in your yard, rain gardens are often designed to capture roof runoff via a downspout extension, a swale or an underground pipe. If you want your rain garden to capture roof runoff, look for a convenient location.

Locating your rain garden in full sun or partial shade will let you choose the widest selection of plants. You can consider a shady area if you select plants that are tolerant of shade. If your preferred location has trees that can tolerate occasional flooding, a woodland rain garden is an option.

An existing depression in your yard could function as a natural rain garden. If needed, you can make some enhancements, such as replanting with suitable plants or adjusting depth or size so it can hold more water. If the depression tends to hold water for more than two days, you will also need to improve the soil's drainage capacity as discussed above, or find another location with better drainage.

Determine Depth and Size

Determining the ideal depth and size for a rain garden is not an exact science, and various authors suggest different methods. Your rain garden will likely function well if you make a reasonably accurate estimate of the two most critical factors — the amount of stormwater that will be captured (inflow) and how quickly it will be absorbed. The depth and sizing method described below is based on these two factors.

The depression will need to be shallow enough to ensure that water will not stand for more than two days, but deep enough to hold the anticipated amount of water. A general guideline for depth is 7.5 cm (3 in.) in soils with relatively low infiltration rates (for example, loam) and up to 15 cm (6 in.) in soils with high infiltration rates (for example, sandy or gravelly soils). To ensure that there is adequate space in shallower depressions, the size of the garden will be adjusted for various soils, as discussed below.

To determine the size, follow these three steps.

1. Determine Inflow

i.                        Estimate the area in square metres of the section of your roof that will drain into the downspout, plus the area in square metres of other hard surfaces, such as driveways or patios, that will drain into the rain garden. Next, estimate the area of lawn that will drain into the garden and multiply that figure by 20 per cent1. The size of the roof area plus other hard surface areas plus 20 per cent of the lawn area draining into the rain garden is the total drainage area (in square metres). For example, the total drainage area might be 170 m2.

  1. Estimate the amount of precipitation that will flow into your rain garden over a 24-hour period. Some municipalities set rainfall capture targets, so check with your municipality’s public works department. If there isn’t a municipal target, set your own based on average local precipitation. Your municipality may have precipitation data for your region; if it doesn’t, this information can be obtained from Environment Canada. An example of a target is 25 mm over 24 hours. Targets will vary from region to region and can be as low as 5 mm over 24 hours.
  2. Multiply the drainage area in square metres (Step i) times the rainfall capture target in metres (Step ii). For example, a rain garden that will capture 25 mm of rain over 24 hours from 170 m2 of drainage area must hold 170 m2 x 0.025 m = 4.25 m3 of water over 24 hours.

2. Determine the Infiltration Rate of Your Soil

For example, if the rate is 15 mm per hour, it will absorb 360 mm of water over 24 hours. Convert the figure to metres (in this case, 0.36 m). See text box.

3. Calculate the Area

Divide the estimated inflow (Step 1) by the infiltration rate (Step 2). Using the example above, the rain garden would need an area of 4.25 m3 ÷ 0.36 m = 11.8 m2.

Soil Infiltration Rate

Knowing the permeability of your soil is essential when installing a rain garden. Sandy soils are highly permeable with a minimum water absorption rate of 210 mm per hour. The minimum absorption rate for sandy loam is 25 mm per hour. For loam, the minimum absorption rate is 15 mm per hour. In clay soils, absorption rates can be as low as 1 mm per hour. You can test the permeability of your soil by digging a small test pit, filling it with a known quantity of water and observing the time it takes for the water to be absorbed.

Rain gardens are designed for average annual precipitation levels. Occasionally, there will be a heavy rainfall and, less often — once every 25 to 100 years — an extremely heavy rainfall. Occasional overflow of your rain garden will most often be accommodated by your own yard and the municipal storm system. If there is any possibility that overflow could cause drainage problems in neighbouring areas, include an overflow system. This can be as simple as an in-ground perforated pipe or shallow swale that is directed towards a less vulnerable area, or an area that drains into the municipal storm system. You can also reduce the frequency of overflow by slightly increasing the size of the rain garden or the depth of permeable soil, or both.

Although following the steps for sizing will give you the optimum size, you can change the size to better suit your yard, your budget or maintenance. You can reduce the size by increasing the depth of permeable soil, decreasing the area that contributes to inflow, or creating more than one rain garden.

Determine the Shape

To capture as much stormwater as possible, a rain garden should be at least 1.5 times longer than it is wide (length is defined here as the face at a right angle to the slope). The 11.8 m2 rain garden in the example above should measure approximately 4.2 m x 2.8 m. Again, if site conditions do not allow for the optimum size, you can adjust as needed.

Many people prefer the appearance of soft, round edges to hard, square edges, and kidney or oval shapes, but you can create any shape that suits your taste and your yard.

Select Plants and Stones

Select perennials, shrubs, grasses or ferns, or all, that can tolerate both wet and dry conditions. Choose plants that are adapted to your region and your specific soil and sunlight conditions. Native plants are well adapted to local conditions and are therefore generally preferred for rain gardens. Non-native plants can also be used, but avoid invasive species (see "References and Resources"). For an attractive garden that will bloom for much of the season, also bear in mind plant heights, colour and bloom time. See the plant list in CMHC’s Landscape Guide for Canadian Homes for help choosing plants.

You can install herbaceous plants (species that are not woody), like perennials, as plugs, potted plants or seeds. Plugs or potted plants will create an instant garden and are easier to grow and more predictable than seeds. Seeds don’t cost as much, but it can take up to three years for the garden to fully fill in. A seed mix can be customized for your conditions, or you can use a shoreline or wet-dry meadow/prairie mix if your local native seed supplier offers it. You can plant shrubs from pots, as bare root seedlings and, in some cases, as cuttings.

Or, you can line the bottom of the rain garden with loose, hard materials, such as pebbles or river stone. A stone-lined rain garden will mimic a stony stream bed, adding a unique feature to your yard (see Figures 4 and 5). You can also include plants in a stone-lined rain garden. To add esthetic appeal, edge the pond with materials such as brick or stone. You can also add a focal element, such as a large rock or a sculpture.
How to Install a Rain Garden

The best time to build a rain garden if you are working with plugs or potted plants is mid-spring, after the thaw, when the soil is most likely to be moist and fairly easy to dig. Plants will benefit from spring rains. Although you can build a rain garden in summer, you may need to water the plants far more often until they are established.

If you are seeding the bed, the best time to install your rain garden is mid-spring or late fall. Seeding in late fall allows the natural, freeze-thaw cycles to work. They help many native seeds germinate without pre-treatment. Ask your seed supplier if any pre-treatment of native seed is required for spring sowing. Shrubs can be planted in either spring or fall, depending on the species.

Begin by laying out the shape and size of the bed with a rope or garden hose. Remove existing lawn with a sod cutter, garden spade or edging tool, being sure to remove all pieces of root. If you have enough lead time, you can smother grass or other plants with heavy black plastic anchored down with rocks and left on for at least two months during the previous growing season. Remove the plastic before digging the bed.

Call Before You Dig

Before digging any test pits or depressions in your yard, locate buried wires and pipes. Call your local service providers for assistance.

Dig the bed to the required depth, as described earlier in the “Determine Depth and Size” section. Remove any remaining roots of former plants or lawn. If you need to improve the drainage of the soil beneath the surface, continue to dig and add other amendments, such as sand, fine gravel or organic matter, to a depth of 0.6 – 1.2 m (2 – 4 ft.). A small backhoe can be helpful if you need to dig beneath the surface. To help the new plantings establish themselves, add compost and work it into the top few inches of soil.

If you dig into a slight slope, use a carpenter's level to help you keep the bed level. Soil from the higher side of the slope can be used as fill for the lower side. On a slope, you will also need to build a low berm along the lower side of the slope edge to retain the water (see Figure 5). The berm can be constructed with soil that you removed from the upper side and covered with a variety of plants or lawn. Gently slope both sides of the berm and compact it by stomping on it. Sod, seed or plant the berm immediately and temporarily cover with a straw mat or straw mulch to prevent erosion.
You can run a roof downspout extension directly into your rain garden. To prevent erosion, install a small bed of pebbles or a concrete splash pad under the end of the extension.

If needed, dig and install an overflow pipe or swale on the lower side of the garden. You can place your downspout extension in the garden. To prevent erosion in the garden, place a small bed of pea gravel or decorative pebbles, or a concrete splash pad, under the extension (see Figure 6). Or, the downspout can discharge onto a lawn area that drains into the rain garden.

Rake the bed so that it is fairly smooth. Use standard planting or seeding methods. See CMHC’s Landscape Guide for Canadian Homes for advice and tips.

If you are covering with stone, place a layer of filter fabric on the surface, then place the stone. To plant among the stones, slit the fabric.

Minimize Impermeable Surfaces

To reduce runoff and beautify the property, the homeowners reduced the size of their driveway by more than 60 per cent by replacing it with plantings. They changed the material on the remaining driveway from asphalt to precast concrete pavers.

Minimizing the amount of impermeable surface area on your property is another way to reduce stormwater runoff and allow water to soak into the ground. You can start by limiting the number and size of hard surfaces to only those needed for your household's regular activities (see Figure 7). You can also combine various uses on hard surfaces. For example, a driveway or patio can double as a footpath.

You can also use porous paving materials that allow infiltration. Where possible, use loose materials, such as decorative pebbles or crushed brick. Where you need a firmer surface, consider using precast concrete pavers with wide gaps. They are designed specifically for stormwater infiltration. Also fill gaps between patio stones or pavers with sand or fine gravel instead of concrete.

On driveways, you can install two strips of paving spaced for the wheels of your car or other vehicles, and plant grass or a low groundcover in the spaces between the strips.

How to Maintain a Rain Garden

Keep the soil moist during the first growing season. If there is little or no rain, you will need to water with a one-hour trickle at least once a week for the first three weeks. Subsequently, water during hot, dry weather. Plants grown from fall seeding will also need to be watered in drought conditions the following season. If you have selected plants that are suited to the soil and moisture conditions, plants in the rain garden should not need to be watered once they are established.

For the first two or three years, you will need to remove weeds regularly. Some desirable native plants may migrate to the site, so try to identify the species before you remove them. You can hand-pull weeds, being careful not to disturb new plantings. Pull weeds when they are immature, before they go to seed. Weeds are easier to pull when the soil is moist. Once the garden has filled in and a root mass has formed, you won’t have to weed as often.

Once the rain garden is established, you can occasionally add compost. Plants that are adapted to sandy or gravelly soil tend to prefer nutrient-poor conditions, so compost should be added only if it appears necessary. To control insects and disease, it is best to use low-impact manual or non-synthetic controls whenever possible. For more information on maintenance, refer to "References and Resources" or to CMHC’s Landscape Guide for Canadian Homes.

Aerate the soil occasionally to ensure it does not become compacted. If over time you find that water is standing in the bed too long, the easiest solution is to make the garden larger or create a second rain garden to catch some of the water. You can also make the depression deeper or further amend soils to improve permeability, but both of these options will require removing and transplanting plants.

Once established, your rain garden should provide many years of enjoyment with little maintenance. You can derive added satisfaction from knowing you are contributing to a healthier natural environment.

Home Price Index

According to statistics released in May by The Canadian Real Estate Association (CREA), the MLS® Home Price Index, the leading measure of Canadian home prices, increased in April 2012.


  • The Aggregate Composite MLS® Home Price Index in April 2012 was up 5.2% year-over-year.
  • Toronto again posted the largest year-over-year increase (7.9%), with more modest gains in Calgary (4.0%), Vancouver (3.7%), the Fraser Valley (2.7%), and Montreal (2.3%).
  • Year-over-year price gains accelerated in April in Toronto and Calgary but slowed in Vancouver and the Fraser Valley and were little changed in Montreal.
  • Single family home prices again posted the biggest gains (6.4%), with apartment unit and townhome sales making more modest headway (3.6% and 2.7% respectively).

The MLS® Home Price Index (MLS® HPI) rose 5.2 per cent year-over-year in April 2012. The increase was similar to those for the previous two months and among the smallest since last August. However, the moderation in overall price gains in recent months masks diverging trends among the major Canadian markets.

In April, the MLS® HPI again posted the largest year-over-year increase in Toronto (7.9%), followed by Calgary (4.0%), Vancouver (3.7%), the Fraser Valley (2.7%), and Montreal (2.3%).

Year-over-year price growth in Greater Vancouver slowed markedly in April and moderated in the nearby Fraser Valley. By contrast, Montreal — a market that tends towards more stable price growth — saw a small uptick in line with the aggregate index.

Toronto’s price index accelerated for the second straight month, consistent with its market balance where negotiations continue to favour the seller. Calgary is also now seeing prices begin to advance in earnest, supported by a strong economic outlook, recent gains in in-migration, and strong full-time job growth.

“Canadian home price gains are generally expected to moderate, but there are a few hot spots where prices are being fuelled by some very strong housing market fundamentals,” said Wayne Moen, CREA’s President. “Toronto has less than two months of supply compared to six months nationally, so it ranks among the tightest of Canadian housing markets. With prices moderating in some housing markets and bucking the trend in others, buyers and sellers should talk to their local REALTOR® to best understand how home price trends are evolving where they live.”

Among the different housing types tracked by the index, single family homes again posted the biggest year-over-year gains in April (6.4%), led by two-storey single family homes (6.9%). The MLS® HPI for one-storey single family homes rose 5.6 per cent from April 2011, while townhouses and apartments saw gains of 3.6 per cent and 2.7 per cent, respectively.

“Just as there are some pretty clear differences emerging across markets right now, there have also been some interesting developments in price trends across housing types,” said Gregory Klump, CREA’s Chief Economist. “The one that really stood out in April was accelerating price growth for the townhouse segment right across the board. In Vancouver and the Fraser Valley, it was the only segment in which prices gains accelerated.”

MLS® Home Price Index
January 2005 = 100
percentage change vs.
 Composite HPI:
April 2012
1 month ago
3 months ago
6 months ago
12 months ago
3 years ago
5 years ago
Lower Mainland
Greater Vancouver
Fraser Valley
Greater Toronto
Greater Montreal

In focus: Price growth among housing types

The MLS® HPI tracks four different Benchmark housing categories: one- and two-storey single family homes, townhouses, and apartment units. Based on detailed characteristics specific to each neighbourhood, Benchmark prices are aggregated for each metropolitan market and the headline Aggregate Composite MLS® HPI.

Two-storey single family homes are generally (with the exception of Montreal) the most expensive of the four Benchmark categories, followed by one-storey single family homes, townhouses, and condo apartment units.

From the depths of the economic recession of early 2009 and over 2010, prices in all Benchmark housing categories exhibited similar trends.

However, beginning in early 2011, price gains for one- and two-storey single family homes were bigger than they were for townhouses and condo apartment units, and accelerated faster. The difference in year-over-year price gains between single family homes and the other Benchmark housing categories is now bigger than at any other time since 2005.

As a result, the townhouse and apartment units have remained relatively more affordable than one- and two-storey single family homes since 2005 from the standpoint of price. For this reason, the recent acceleration in townhome prices in all markets tracked by the index may indicate the beginning of a shift in demand away from the increasingly expensive single family sector.

A similar acceleration in prices has yet to materialize for apartment units, which are more affordable than townhouses from a price standpoint. One reason for this could be that as an alternative to expensive single family homes, townhouses are viewed more favourably than apartments by families looking for housing in more centrally located areas. The apartment segment is also better supplied, and recent trends for multiple units under construction suggest that this may remain the case going forward. Another reason might also be the almost daily news media stories about potential price corrections in condo markets.

Copyright CREA reprinted with permission