Your cactus may flower if conditions change. Neglect it then water it then neglect it and see?
Could also be structural plants or trees rather than colour. Bamboo, pampas grass, are attractive.
And there must be public gardens or planters?
Here there are currently masses of yellow daffodils everywhere, on verges and roundabouts where the council have planted; also on minor roadsides where house owners have planted a single line for a mile .
And in planters in towns there are fragrant hyacinth, one of my favourite flowers.