More and better plant knowledge
Mortality rates for urban trees are super high. This could be fixed with simple education such as: don’t plant trees too close to buildings, don’t pile up mulch around the base of the tree, pick NATIVE species, pick only hardy pioneer species for stressful areas like parking lots, and avoid damaging the trees with weed whackers and lawn mowers. Give trees lots of space of dirt around them so water can soak in and reach their roots.
For smaller green areas, do native flowers and grasses, a good mix of them. And know their qualities and ways so they can be somewhere they are happy
For example relevant to Eastern USA- Purple Coneflower loves harsh, hot environments with poor soil, so put it on the edge of a pavement. There are also tons of flowers that grow specifically in rocks and gravel, so they would love that area bordering the concrete walkway that kills the lawn grass.
Flat-out ban pesticide use in lawns. That stuff hurts our health and our water supply and our ecosystems.
Also WIGGLE THE STREAMS. Straightening out the wiggly streams into straight drainage ditches means they hold less water. Imagine a pipe that is bent and wiggled stretched across an area a certain distance wide. Now imagine a perfectly straight pipe stretching across the same distance. NOW imagine stretching out the wiggled pipe so it’s straight. It’s much longer than the straight pipe now, so you can see how it holds more water.