Actually, we use orange oil to keep our cats out of the potted plants. We
put in around the rim of the pot. I worry that the acidity wouldn't be good
for the plant so I haven't intentionally put in in the dirt or on the plant
but any accidental contact has not had any noticible effect.  

It can be found on various websites if you search for "orange essential
oil" and look for one that is 100% natural. Here's one site:

http://www.mothernature.com/shop/detail.cfm/sku/50809/S/400397

Actually, we got the idea because I was drinking orange juice one day and
got the same reaction from my cat - the scrunchie nose and backing away.
(you might want to try letting your cat sniff OJ before buying the orange
oil just to see if it works as well)

Actually, just for the heck of it, I did a search for banana essential oil
and came up with a few places that sell that too. Here is one link that I
found. I've bought from mothernature.com but I've never heard of this place
before.

http://www.nmcnews.org/banana.html

Good luck.

it is better to teach the cat not to get on the table.  The classic
approach is to use a spray bottle of water adjusted to produce a
stream instead of a spray.  This lets you quietly squirt the cat
without it associating you with the discomfort of getting wet -
instead it associates being on the table with getting wet.