Maybe it's this guy: A little over three years ago, Alex Padro from the Shaw Main Streets program asked Frank Asher, an artistand “guerrilla gardener,” if he wanted to do some sort of green space at the corner of 9th and N Streets NW.
Source: https://www.borderstan.com/2011/10/27/old-city-green-uses-urban-gardening-expertise-as-competitive-edge/