Semi-persistant flowers
 

Would it be possible to make it so flower gardens can't be picked by anyone but the person that planted them until they're below a certain constitution? It's more than a bit disheartening to spend the time planting flowers for decoration, only to have someone run up and pick them right away.
Maybe as long as they're above 50-75%, only the planter can pick them?

I'll recommend this.

And I'll state the opposite end. Enraged person plants flowers in front of doors and lets nobody pass. FOR DAYS....

easy solution: make them non-blocking.
use a shovel or scythe to harvest.