conscientious neglect
n. Gardening in a conscientious manner by using hardy, native plants that don't require chemicals or other environmentally destructive care.
Examples
2002
The speakers for the day include:

* Ken Parker, the owner of Sweet Grass Gardens near Ohsweken in Six Nations of the Grand River.

Parker's an increasingly in-demand speaker whose garden centre specializes in plants native to this part of North America. Sweet Grass Gardens was North America's first native owned and operated nursery, and it is also one of only a few nurseries in this part of Canada that deals almost exclusively in plants — grasses, perennials and annuals — that were indigenous to North America before Europeans arrived. Parker sells only species, or wild, plants — no hybrids or cultivars.

"I began the business because I couldn't get anything to grow here," he said to me years ago. "My wife loved roses and I thought they were annuals."

Native plants are, by definition, hardy. Generations of growth in the wild develops a natural tolerance for North American soils, its extremes of heat and cold, its summer humidity and droughts, and even its diseases and pests. Native plants also naturally attract a wide variety of indigenous birds and butterflies since they've evolved together and are mutually dependent for pollination and for food.

"I don't have time to look after things here," Parker said. "And I don't have to say 'good luck' when people leave with plants. I know they'll do fine."

He'll be speaking on Conscientious Neglect — using tolerant species that thrive without intervention.
—Robert Howard, “Gardening goes green,” The Hamilton Spectator, February 07, 2002
2001 (earliest)
Native plants thrive on conscientious neglect.
—“Low Impact Roadway Design,” North Logan Design Standards Technical Manual, February 15, 2001