Oct. 6 2021 02:34 PM

Solid planning turned a complex installation into a rain-powered native habitat.

Sometimes clients have a crystal-clear idea of what they want out of an outdoor living space design, whether it’s an area built around visiting with friends on the patio or space for the kids to run wild. Other times, however, clients come in bursting with different ideas, and it’s up to the designer to synthesize them into a cohesive vision. That’s what Kelley Hanna, owner of Plant Goddess Landscaping in Pasadena, California, took on for clients who had big dreams for the backyard.

Hanna was initially brought onto the project as a referral from a neighbor that she had done some work for. The area already had a lot of the benefits of being surrounded by nature. There was plenty of local wildlife and lots of space to work with in design. The homeowners, who had lived there for about 40 years without doing much with the green space, were looking to develop an outdoor living space that embraced those natural aspects, which was a perfect fit for Hanna.

“I’m about trying to create awareness and educate the homeowner about how we need to plant California native plants and support our local ecosystem,” she says. They wanted to support the wild quail found in the area as well as pollinators, including the bees from several local keepers and monarch butterflies.

The client was also looking to develop areas to grow food, including several olive trees, without installing a greenhouse. Those were all great goals for Hanna, but another angle she was adamant about discussing early in the design phase was irrigation. The property still used metal sprinklers that hadn’t been updated in years and weren’t watering as effectively as they could. “I told them, even though we’re going to put in all this landscaping, your water bills are going to go down,” she says.

With other disparate types of landscaping involved, such as oak trees, a native plant meadow and water features, the project was a huge challenge. But the client was willing to put the money behind Hanna’s work and stay out of her way as the design came together, she said. Hanna credits part of that trust to her accumulated experience.

“Now that I’m more seasoned, I tell people, ‘If you want a good yard, tell me what you want. Of course, I want your input. But then let me do it,’” she says. “Because between what’s on paper and what ends up happening, I do a ton of field changes as I start to see it come together.”

While the work was ongoing, the homeowners would bring their grandchildren out to watch the boulders being placed or to see the trucks coming in.

“It really did make it into an entire family experience for them,” she says. “It was so fun.”

Building a plan

Developing the appropriate irrigation design for such a complicated layout wasn’t easy, she says. On top of the additions to the landscape, the property was already home to several citrus trees that the client wasn’t enthusiastic about moving. She placed a pergola in the center of the design and split the different landscaping sections into quadrants around it.

That allowed her to fine-tune the irrigation zones for each area effectively.

“So I had the fruit trees and roses and the Mediterraneans in these two areas, and then the coast live oaks and the natives here,” she says.

To make matters more complex, the previous irrigation system wasn’t well-mapped, on top of its age. Building around the system wasn’t going to be an effective option. “I started over,” she says. “It’s too big of a project. I didn’t know what kind of pipe was down there and how old it was.”

Hanna used the quadrants as guidance for the irrigation installed, whether it was drip line for some of the landscaping or rotating spray heads for the meadow area. To protect the drip irrigation from the wildlife that would be visiting the living space, she buried it lightly with a few inches of mulch on top.

When it came to water features, Hanna used two approaches, each with a different purpose. She installed a double-tiered basin fountain that could be enjoyed closer to the patio and house. But out among the flowers, she placed what she called a pollinator watering station. The fountain is a flat boulder with a hole drilled up through the middle with a subgrade basin, which allows the water to trickle shallowly across the top of the rock. This is safer for pollinators like bees and butterflies, which would be in danger of falling into the deeper water source.

Working with nature

The house had so much roof area that Hanna was able to use two of the downspouts to direct water into a rain garden. While she usually does that kind of work on the surface by contouring the land, the garden’s pathways were in the way and the client didn’t want to use bridges in the design. Hanna used a subgrade system with decomposed granite hardscaping and drainage paver rolls to direct the water throughout the rain garden from the downspouts.

“It was a lot of labor,” she says, including marking beforehand where trees and other elements would be placed. “I had to map it out.” Using permeable hardscaping in the pathways allowed water to flow without requiring bridges in the design while making the most use of rainwater.

For the rain garden, her goal was to slow the collected water down so that it would spread through the soil, giving the plants plenty of opportunity to gather what they needed and sink it so that it wasn’t running across the surface. “I tried to work it so I got as much coverage in the yard as I could get,” she says. “Because if we get a lot of rain, I can turn those stations off for quite a long time and we don’t even have to irrigate that area. That way you can really save a lot.”

Hanna uses a soil probe regularly to check that water is moving through the area efficiently, but the way the plants have started to thrive in the irrigated space is a solid indicator for her as well. “A soil moisture probe is important because you can’t tell just from the surface,” she says. It allows her to get a read for how much moisture is in the soil and if it’s reaching the appropriate depth for the trees and other plants.

“If we get enough rain and I utilize that rainwater, you’re going to have some crazy happy California native plants,” Hanna says. This approach works best with spongy soil, which will allow the water to remain available. A more compact soil like hard clay will need a different solution to get water to flow. “It’s all about the soil, so when it does rain, the soil will be able to hold on to the water.”

The landscape is teeming with wildlife, Hanna says. While she was out taking pictures of the finished project, she spotted two of the small wild quail that the homeowner had specifically wanted to support with the installation.

“There are literally wild quail running around in the shrubs, which is fantastic,” she says. “There are tons of birds. I’ve even seen them nesting in the coast live oaks. There’s tons of hummingbirds. I’ve seen them drinking from the fountain.”

The outdoor living space gets lots of attention from the bees maintained by local keepers as well. They’ve even brought neighbors together, as one local keeper noticed that in the mornings his charges would often make a beeline straight to the property. At the end of the season, he shares some of the honey with Hanna’s clients as a kind of payment for providing so many flowers for them.

It turns out that the new irrigation system hasn’t quite paid off, as Hanna initially said they would be paying a lower water bill. But the homeowner’s irrigation bill hasn’t gone up, she says. They’re watering less than they were before the installation with more efficient systems. And in supporting even more life in both plants and animals while using less water, Hanna sees it as getting more for what they were already spending.

With the project completed, Hanna is most proud that one of the homeowners, who had initially been skeptical of the worth of the installation, is out in the garden almost every day, she says.

“That’s definitely a feather in my cap,” she says. “I’ll drive up there in the morning and he’s out in the garden. And I can tell that the kids have been over because you’ll see the tracks from the bikes on the DG pathways. It’s like a big park for them.”

“I always feel that I’ve achieved something if people who didn’t ever go out into their yard are spending all this time outside and their quality of life has been enhanced,” she says. “That, to me, is just the best.”

The author is the editor-in-chief of Irrigation & Green Industry and can be reached at kylebrown@igin.com.