SOUTH PORTLAND — A contentious proposal to limit the use of synthetic lawn-and-garden pesticides in the city will get more thorough consideration in the weeks ahead.

The City Council postponed a final vote on the proposed partial ban Wednesday night and has scheduled a workshop on June 13. A council vote is tentatively set for June 20.

The council gave the proposed ban unanimous preliminary approval on April 4 after hearing from both supporters and opponents. At the time, councilors called for several amendments to clarify aspects of the draft ordinance, including enforcement and waiver processes.

“I think it’s really prudent that we take our time,” Councilor Patti Smith said Wednesday. “It’s a really complex issue.”

Activists on both sides of the issue say South Portland’s effort could be copied by other communities across Maine and beyond. Portland officials have announced plans to follow South Portland’s lead if it succeeds.

Supporters say the ordinance would be the most far-reaching and environmentally progressive law of its kind in the nation, following a similar measure passed last year in Ogunquit and the Healthy Lawns Act that’s being rolled out in Montgomery County, Maryland.

But opponents say South Portland’s proposal would be largely unenforceable as written and liable to divide neighbors into warring camps of scofflaws and watchdogs. They also say organic pesticides sometimes aren’t as effective and can be toxic if used improperly.

In an April 14 memo to the council, Sustainability Coordinator Julie Rosenbach acknowledged that the ordinance would be “challenging” to enforce, especially on private property.

“Our intention is not to approach implementation in a punitive way, but rather to use education and outreach to promote organic land care practices and help the community with this transition,” Rosenbach wrote. “We recognize there will likely be scofflaws, and therefore have allowed for warnings and fines if persons are caught in violation of the ordinance. This approach is consistent with other pesticide ordinances and if it proves to be problematic can be addressed in the year-three review process.”

To speed up the waiver process, Rosenbach recommended that the chairperson and one other member of the proposed Pest Management Advisory Committee be authorized to rule on waiver requests within five business days. At least one of the authorized members would have to be a licensed pesticide applicator. Denials could be appealed to the city manager, who would have three business days to respond.

Rosenbach also recommended several language changes to align the proposed ordinance with state and federal law, and suggested an amendment that would ban all organic and synthetic pesticide use within 75 feet of water bodies and wetlands.

The proposed ordinance would prohibit the use of synthetic lawn-and-garden pesticides and herbicides on private as well as city-owned property. Retailers could still sell the targeted products, including glyphosate-based Round-Up, neonicotinoids and weed-and-feed applications. And residents could still buy them.

But only pesticides allowed in organic farming or exempted from federal regulation could be used within city limits. The local ban also would exempt commercial agriculture and playing surfaces at golf courses, and it would allow waivers for public health, safety and environmental threats, such as mosquitoes, poison ivy and invasive tree insects.

If approved, the ordinance would apply to city property starting May 1, 2017, and broaden to private property May 1, 2018. It would be reviewed during the third year for possible revision. Following an initial warning, violators would face escalating fines of $200, $500 and $1,000 per offense.

The ordinance would apply to the municipal South Portland Golf Course and the privately owned Sable Oaks Golf Club starting May 1, 2019. Playing surfaces on the private course would be exempt from the ban, while tees and greens on the municipal course would be exempt for three years after adoption.

Twenty-six Maine communities have some sort of pesticide-control ordinance, including Ogunquit, Brunswick, Rockland, Wells, Lebanon and Waterboro.