One tree growing in Baltimore won’t make that much of a difference.

But thousands of trees will.

Block by block, in neighborhoods as diverse as the gabled row houses of Reservoir Hill to the turreted churches of East Baltimore’s Highlandtown, workers are planting redbuds and black gums, hackberries and buckeyes. They are transforming streets in a city known for its tight quarters and blighted alleys — a place more gray than green and often riddled with trash, graffiti and boarded-up vacant shells.

Shortly after it was formed from the merger of five watershed organizations in 2009, Blue Water Baltimore began to undertake more projects on a neighborhood scale. One green alley or green street was nice; 11 blocks with 130 trees in East Baltimore was even nicer. Grants from Baltimore City, the Chesapeake Bay Trust and other nonprofit organizations have allowed the organization to tackle that larger work and build demonstration projects to show what a greener Baltimore looks like.

In September, Blue Water Baltimore got word it would receive $500,000 from the National Fish and Wildlife Foundation for its Deep Blue greening project, which allows the group to focus on five neighborhoods and “go deep” with getting the community involved in directing the tree plantings, abating the trash problem and building green infrastructure with porous pavement in alleys.

By the time officials from the EPA and NFWF announced the grant, Blue Water Baltimore staff were already in the Highlandtown neighborhood digging tree pits and moving new trees into position.

Carl Simon, program director for Blue Water Baltimore, said there’s a good reason why the organization doesn’t want to let the grass grow under its feet.

“We’re immediately going into neighborhoods and starting projects as soon as we can because we want to show the community that we’re not all just talk,” he said. “Our guys are out there, all day, every day, removing impervious surface…if there’s an existing tree pit, we expand it. If there’s no tree pit, we create it.”

In addition to Highlandtown, the targeted neighborhoods include Oliver, Cherry Hill, Mondawmin and Belair-Edison. Mondawmin was one of the neighborhoods at the center of the unrest after the death of Freddie Gray, who died in police custody in April. Oliver, a struggling neighborhood, became well-known in 2002 after the entire Dawson family was murdered when their home was firebombed. Mrs. Dawson had repeatedly told police about drug-dealing in the neighborhood.

The Baltimore Department of Public Works has also committed $2.2 million to city greening projects from its stormwater fee.

Interest in greening the city is not an accident. Baltimore’s proximity to the Chesapeake, its densely populated neighborhoods and its pockets of extreme poverty make it an attractive place for investment. Many of the funders said in October at the NFWF press conference in front of the Prince of Peace Church in McElderry Park that the city’s leadership is interested in fixing problems and wants to work with nonprofits and neighborhood partners to make it happen. Urban residents are increasingly aware that they can harm the Bay even though they can’t see it; and with appropriate resources, they can begin to end that harm.

“There’s a density of folks trying to green the city and manage stormwater, and then there’s the Bay,” said Collin O’Mara, the chief executive officer of the National Wildlife Federation, at the NFWF event.

The EPA’s Region 3 Administrator Shawn M. Garvin agreed.

“People think if you can’t see the water you’re not having an impact on it,” he said during the event to announce the grants as he stood in front of a dense block of row houses. “But investments in clean water, here, where we’re standing, have a lot more benefits than just cleaning up the Chesapeake Bay. There are clean air benefits, the reducing of heat islands, community benefits….We know we can’t do everything with green infrastructure, but if you spend a little more to get broader benefits, it’s worth the investment.”

City leaders nationwide know the benefits of trees and can recite them when seeking money in tight budget times. Trees help lower gas and electric bills, can increase foot traffic on a street and lead to less crime. They bring in pollinators, help grow food and soak up stormwater to control flooding and reduce pollution.

But perhaps nowhere are the benefits more clear than on a walk with Elise Victoria, Blue Water’s urban forestry manager. Turn down one corner and the street is strewn with trash. No one’s walking down it. The sun beats down on the pavement, making a warm fall day feel oppressive.

Turn the other corner, though, and trees abound. The air is cooler, the shade welcoming. Young parents are walking with strollers. A jogger comes by slowly, avoiding the equipment that Victoria and her co-worker Corbin Sutton are using to set trees in the pits on the street.

The neighbors have noticed the change, Victoria said. Three years ago, when they began planting some trees in Highlandtown, neighbors weren’t so enthusiastic. The equipment was noisy, the streets could be too crowded for parallel street parking and there was a belief that the trees would attract rats and insects.

Now, Victoria said, it’s easy to talk residents into the trees. All she has to do, she said, is point to the blocks without them to make the case.

“You can imagine, with no trees on this block, it was desolate,” she said. “Places like this get left. We want to make sure they are included.”