At first, our landlord seemed pretty hands-on: stopping by to see how we were doing, checking the plants to make sure the sprinklers worked, etc.

Cork is more resilient, supposedly easier on the back but how long do you really stand on it.

And then there was the plant nazi who was assigned to monitor people's yards, and started bugging me about the nice new bark I put around the plants in front of my unit.  

Dogs tear up yards, fences, plants, landscaping.

In the mean time, keep helping everyone by planting trees. 

How about buying a big full plant or tree or three and put them in big pretty pots to put in that space.  

If you on the West coast title plants have been moved to the Philippines.. we get title reports or commitments next day if requested and for free as noted above if your a RE professional and or giving any kind of decent business to a title and escrow company this is how they keep customer loyalty..

An example would be the huge Boeing plants.  

The tenant expressed interest in it, so I left it as the gift.I have also given a small plant on occasion.I always leave a greeting card.

Any kind of flower plantings will have to be pruned, headed, weeded, edged, etc.If it was a small yard, I'd just cover the whole thing with concrete and tell the tenants they can grow plants in pots.