Cat repelling plants

[Hitch]

We have a area of gravel outside the front of our house which the cats seem to think is a litter tray. We dont have a cat, so it really annoys me.
Tried powdered cat repellant, that works for 24-48 hours in the dry, but as soon as it rains its no good.

Apparently bludgeoning them to death with a crow bar isnt an option either.

I hear lavender works well as a cat repellent?
Neither of us are very green fingered, if i put a trough in the middle of the gravel with a gert lavendar plant in, that should be pretty low maintenance.... does lavendar even grow in the winter?

[kellys_eye]

Citronella oil - you can buy it in bulk quite cheaply and use a spray bottle. Smells like insect repellent (which it is commonly used for) and our cats hate it!

[boxedin]

http://thescaredycat.com/cat-repellent- ... ally-work/
lavender is one of them