From a rooftop swamp cooler watering a desert hackberry to a ferrocement cistern that holds 1,300 gallons of water, Saturday’s third annual Home-Scape Tour covers a wide variety of water-harvesting systems.

The systems at the self-guided tour’s some dozen home sites, two government landscapes and Manzo Elementary School were created with the help of Watershed Management Group, or WMG.

The nonprofit group runs a cooperative that organizes volunteers who help build water-harvesting systems. It also offers workshops.

Using a quarter-inch irrigation tube to guide water from the evaporative cooler’s bleed line to a plant is one way Martha Retallick, owner of Western Sky Communications, harvests water on the cheap.

“There’s a lot you can do very inexpensively and for free,” says Retallick, who sculpted her water-saving landscape in 2008 with WMG’s Green Living Co-op.

Her mature, woodsy yards hide the deep basins and swales she and volunteers dug to collect rainwater, diverting it to plants and away from her central Tucson house. Her lush bushes and trees rely solely on rainwater, swamp cooler water and gray water she hauls from the kitchen and shower.

Retallick’s home also demonstrates sustainable living practices, as do most of the tour’s other stops. She reuses prickly branches from her mesquite and ocotillo to loosely cover two sunken vegetable gardens. That protects the soil from feral cats.

The gardens are rimmed with concrete she reclaimed from a nearby demolition project. The small but constant amount of compost she generates from kitchen and yard scraps get mixed into the soil. Fallen leaves fill the basins with mulch, as does mulch she gets for free from a local landscape company.

She transplants volunteer plants –seedlings that sprout naturally – in pots that were discarded by others.

Nicolas Siemsen’s home near Retallick’s similarly shows some sustainable living practices, including recycling of materials, a raised garden bed and backyard chickens. The steel-reinforced concrete cistern he installed in May collects water to irrigate the yards’ mature and new plants. The cistern and the rainwater collection basins keep water from flooding the yard and potentially the house he and his wife own.

“We see it as a way to protect our house at a price that we can afford,” says Siemsen,a geographic information systems analyst.

Contact Tucson freelance writer Elena Acoba at