In 1999, when Mike and Mary Kulseth built their home in Andover, all they wanted for their yard was a “carefree” low-maintenance landscape. “I just wanted to mow grass,” Mike said.

So the couple had a landscaper lay sod and plant spirea and barberry bushes, surrounded by tan landscape rock — the typical suburban yard. Green turf carpeted the 5-acre lot all the way to a back wooded area, which the couple let go wild.

“Then I decided just to do a little garden around an oak tree,” said Mary. “Even though I knew nothing about gardening.”

So Mike dug out a section of sod, and Mary planted easy annuals such as marigolds and zinnias. Over time, the garden grew, as did Mary’s confidence to try staple perennials — daylilies, coneflowers and groundcover lamium in the sun, with hosta in the shade. “It was all trial and error,” she said. “If something didn’t work, I dug it out.”

By 2002, Mary was retired and had more time to dig into researching plants and strategically designing her gardens according to bloom times: peonies and lady’s mantle in spring, ‘Stella de Oro’ daylilies, coneflowers and black-eyed Susans in mid-summer and purple plumes of astilbe in August.

“I was so excited when everything came back in the spring and it looked so pretty,” said Mary. “I thought, ‘This is really fun.’ ”

Pond people

Mary’s newfound passion rubbed off on Mike. “I’ve always liked water features,” he said. “And we had plenty of room for one.”

Mike visited landscape supply stores to learn how to install a pond and waterfall. It took some digging. “Ponds weren’t as popular back then,” he noted, and there weren’t as many DIY classes.

Undaunted, Mike spent many evenings and weekends, armed with just a shovel, digging a hole for their 3,000-gallon pond. The rubber liner he needed was so heavy that it broke his trailer, and was nearly impossible to transport to the back yard. Mary, Mike and their son hauled 40 tons of rocks down to the hole.

Finally, the pond complete, they filled it with water and aquatic plants — sweet flag and water hyacinth, and hardy water lilies with pink and yellow blooms floating on the surface. They planted the water lilies in plastic hanging baskets so Mike could retrieve them easily with a rake and trim the foliage before winter.

Mike was so pleased with the results that four years later, he built a smaller second pond and a flagstone walkway to connect them. “I wanted the waterfall in that pond to be more aggressive and noisier,” he said. “So it has a steeper design.”

The larger pond is home to several dozen orange koi and goldfish, many of which Mary named. She was devastated when mink ate every single fish one winter.

“That year, the pond didn’t freeze, and they were sitting ducks,” said Mike. Now they net their fish and overwinter them in huge tanks in the garage where the Kulseths’ grandson loves to feed them. “I wish we would have videotaped that first year,” said Mary. “Mike was falling in the pond trying to catch them.”

Come spring, Mike is deep in muck, cleaning out the pond basin. “Sometimes I think I should be golfing instead,” he said. “But after it’s done, we get to sit back and enjoy it all summer.”

Every year, the couple have improved and enhanced the tranquil setting surrounding the ponds. Waves of pink and purple phlox decorate the entrance to the water features. Mike built a deck and pergola, which is covered by trumpet vines and purple clematis, on one end, with a bench on the other. A pineapple-shaped fountain from Menards that attracts birds was a new addition last summer. They’ve also planted a row of Diablo nine-bark to create a backdrop between the pond gardens and the woods beyond.

Point of pride

Mike and Mary strove to create water features and bordering gardens that blend with the surroundings. Their yard was on a pond tour in 2006, and people commented on the natural free-flowing style, said Mike. “The professionally designed and installed ponds can look sterile,” he said. “I’m proud of ours because we did it ourselves.”

For whimsical personal touches, Mary sprinkles the gardenscape with frog figures perched on lily pads, tiny birdhouses suspended from trees, and a piece of driftwood the couple pulled out of a river in Wisconsin.

Each spring, Mary tackles a new garden project. “Mary says jump,” joked Mike, “and I say, ‘How high?’ ”

As a respite during hot summer days, Mary crafted a shady woodland garden with gnomes peeking out among ferns and hosta under a clump of maple trees.

“Gnomes used to give me the creeps,” she said. “I pick the ones that don’t look mean and grumpy.”

After 13 years, the couple have created a lush suburban oasis amid the green turf, which still covers a substantial part of the large back yard.

“Your eyes need a spot to rest,” said Mary. “And the green backdrop really makes the colors pop.”

Although the Kulseths didn’t achieve their mission of a low-maintenance yard, they wouldn’t trade their labor of love for anything.

“We don’t plop in front of the TV — our gardens are our entertainment,” said Mike.

Mary agreed. “I turn on my music and start deadheading,” she said. “It’s heaven.”