The city is finding how hard it is to change old habits, even when the benefits are obvious.

The habit in question is indiscriminately dumping stuff in the trash, even when you know the state's overburdened landfills are filled with rubbish that could be recycled.

A comprehensive curbside recycling program would be more effective in the long run, but the paltry response to even minimal green-waste recycling is distressing.

Selected communities have blue recycling bins, but few people have converted to the discipline of stowing green waste in them.

City officials say they plan to ask residents what it will take to get them to comply. They should do that promptly.

The answer is likely to be multifaceted. Many with verdant back yards will point out, with good reason, that the bins are too small. For those with small yards and little storage space, they do quite nicely.

The city survey is sure to air justifiable complaints that curbside pickup dates are too infrequent and that community drop-off points are too few. People not in the habit of recycling garden waste, which the city grinds into mulch, will need a nudge of some kind to adopt it. Even simply adding reminders on bins might help.

But generally there's little incentive to change this habit — you don't get a nickel back for your trouble. What you do get is the satisfaction of knowing you've done your part to keep our landfills from overflowing.

Until this thought becomes enough of an incentive, and unless there's a radical shift, the city may eventually make it mandatory and assess fines if people simply go on trashing their green waste.

Anyone with a less painful fix should let the city know.

So far, the voluntary approach doesn't seem to be working.