Master Gardeners are part of a network of not-for-profit associations throughout North America. Members share a common interest – a passion for gardening and a willingness to share (at no cost) environmentally responsible gardening knowledge within their communities. Operating under the umbrella of the British Columbia Master Gardeners, the Thompson Shuswap Master Gardeners chapter was established in 2010 and its members have volunteered 10,000 plus hours throughout the Thompson-Shuswap region.
What if we told you your garden could save you money, support your community, and even help the planet? That’s the power of water-wise gardening.
Every raindrop that hits your roof or falls on your yard has a journey, and you can choose where it goes and how it flows. It can be a resource — if you know how to use it.
In the Okanagan, you might think there’s not much rain to work with, but spring showers can add up quickly. You’ll see just how much water you could be harvesting with a simple calculation. Measure your roof area (length x width), multiply that by the average rainfall (in inches), and then multiply again by 0.62. That gives you the number of gallons you can collect. For example, just 1 inch of rain on a 1,000 sq ft roof yields 620 gallons of free water!
Rainwater is a Real Resource for the Landscape
Your roof is a rain-catching machine. With 620 gallons from a single rainfall, your garden could thrive — without ever turning on a hose. There are two main ways to capture it:
Passive systems, like swales, berms, or rain gardens, allow water to soak naturally into the ground. If you’re more “set it and forget it,” passive capture is your best friend.
Active systems, like rain barrels or cisterns, collect water in containers, often requiring pumps to distribute it later, maintenance required.
How big should your rain garden be? Take the estimated gallons of rainwater you want to capture and convert them to cubic feet (1 cubic foot = 7.48 gallons). For 620 gallons, that’s roughly 83 cubic feet. That could be a garden 10 feet long, 8 feet wide, and just 6 inches deep. It doesn’t have to be deep to be effective. It doesn’t even have to be those dimensions, you can make it the shape you want as long as the total area fits your needs. In this case the total care will be 83 cubic feet. Place your rain garden at least 10 feet from your home’s foundation for drainage safety and give three feet of space from sidewalks or property lines. Even a 150 sq ft rain garden can have a considerable impact.
Planning Your Water-Wise Landscape
Step one is observation. Sketch a map of your space, including driveways, walkways, patios, and the home. Don’t forget to mark where the north is — sunlight and shade matter. Watch where water naturally flows, puddles, or causes erosion.
Identify microclimates — those sunny driveway spots or shady backyard corners. These determine where different plants will thrive. Then, dig into your soil — literally. Is it sandy, clay, or loam? Start building rich, sponge-like soil by adding organic matter. You can even use the Garden Bench article from last month.
Choose Plants with Purpose
Now the fun part: designing your plant palette! Think long-term. Great gardens evolve over time. Do you want shade? Pollinators? Picking native plants will reduce overall water needs. Tools like Xeriscape can help you find beautiful, drought-tolerant natives — even ones like Gaillardia aristata (Brown-Eyed Susan) with striking blooms.
Plant in layers — trees for height and shade, shrubs for structure, and groundcovers to reduce water loss.
A water-wise garden is more than pretty — it’s smart, sustainable, and built to thrive.
Submitted by Sumer Seiki