I'm not being snarky, I really don't see how growing plants would increase fire danger.

If they did big patches using drywall compound you can probably just wipe them and remove them with a wet sponge and then fill, not patch the holes and touch up and be on your way.We had a tenant do something like this a long time ago, they patched over their tiny nail holes, turning a 1/16th hole into a 4'-5" god awful mud smear over textured walls, they then for some reason primed over the patches, that was considered damage to us, as it required retexturing the walls to blend in the patches and then repainting the entire walls, the patching cost that tenant about 2K.

She has outdoor plants and such.

For example, The city where our senior complex is located upgraded their sewage plant and increased the water/sewer rates by about $80 per unit.

Would you require that they remove the garden and plant grass back where it was?

When a tenant asks if they can plant flowers, I'll pay for half of the perennials.

As soon as you close you should have your management change letter ready to post or nail and mail.I have a tenant now that I'm evicting for non-payment, but she is also a hoarder-type with trash and containers of plants outside her apartment that she refuses to move. 

She says she loves plants and keeping the home clean etc.

I just planted extensive and expensive foliage at a triplex and the plants need daily watering now, and every other day watering for a few months.

I think for them they like the larger units and many have planted gardens in the back yards.