A cat of your own would work! As for the plant remedies, seems they don't work. The only reason cats are using your planting area as a toilet is because the soil is nice and loose and they can scratch it easily. If you've got somewhere else in the garden you've not cultivated yet, and its open ground, turn that over and they'll go there. As for where they're going currently, remove all trace of their doings and either put in lots of pea sticks with string wound between them, or holly or berberis,anything prickly, branches laid on the soil. These can be removed as the plants get bigger and cover more ground.
A word about rue - it's not good for human beings either - brushing against it on a sunny day can cause severe blistering of the contact area on skin.

mulching with broken slate on your flower beds and do what bamboo sais ie give them a toilet you dont mind them using should work quit well . apparently if you use lion droppings it keeps cats away as it scares them but i have my doubts and wouldnt know as my 6 dogs keep the cats in check .

Chillie powder? Just read that rentokill now have a squirrel deterent that contains chillie. Trials show that squirrels don't come back after the irritation that the product causes. Cats are always licking between their paws and might find it very off putting. Our neighbour has placed a black cat with glowery eyes on the fence where they come over. It made me startle a bit when I first saw it. It seems that there are less cats about since it was placed there.

try garlic thy dont like that rub around the gaeden

There is no real solution other than to not leave ground nicely dug over with nothing in it our planting is, by and large, so dense that even our own cats aren't a problem. We also cover the scree type beds with a good layer of pea gravel which the cats don't appreciate. Insects don't like the smell of garlic, to my knowledge it does not bother cats. I would not put down chilli powder as there is the potential for eye damage.

I was told to dry used teabags and put a few drops of eucalyptus oil on them then put them on the garden.

not saying it`s 100% effective,but a liberal spreading of pelleted chicken manure works for me, but as other half keeps reminding me that it 'stinks',but that is only until it is wetted. i presume it`s the smell that deters them? unless it`s me growling like a lion at them!!! LOL

As a cat lover and a gardener I certainly wouldn't use chilli pepper. Resisting having nicely turned over soil works best but prickly things are very good laid over rows of newly sown seed.

I really sorted out my flower beds during the winter and was about to put down some mulch when I noticed a cat using the beds as a toilet so putting down mulch would have made it even more desirable so after I dismantled my mini greenhouse I used the wire shelves to put over the garden and by jingo it works, no more cat toilet. I can remove them when the plants fill the gaps.

Good one Cammomile!

The fact that so many different cat deterents are suggested shows how annoying is the problem of visiting cats. Especially at planting time in the veggie garden. Ones own cat can be a villain too, as a bird killer and fledgeling stalker. When one of ours was young he was an expert.....I felt terrible about it. So I do not keep a cat now after the last one died. Our next door neighbour has put wire netting in his window boxes in desperation, and cats with glowery eyes nailed to the fence. I can't be bothered, I just hoe under the Choisya and hope they go there.

cats are infact trying to be clean so like to bury there droppings in soil etc . the broken slate is real hard for the to get into bye nature and it will help keep the plants damp with membrane ofcourse . i find a shot gun can be very effective . only joking lol .

I have found that Napthalene flakes (moth balls) works really well the only thing is it has to be re applied after rain.

'Amazing' a very popular subject...silver foil i have also been told is a good deterrant by my sister who has 2 cats of her own, one of which is a bengal cat who is not normally scared of anything & evan he legs it at the sound...i dont really want to use anything that they might get on there fur or skin, jst a deterrant while im at work etc....i think i must be the mad crazy man of the neighborhood to all the cat nearby after the amount of times ive ran down the garden shouting & waving my arms about in a loopy manner......many many thanks for the idea's they have been noted & no doubt i shall try a few at some point..(except the shotgun of course)lol

Please let us know which one(s) work best will you?

No ground left dug over and open to puddy cats using as a loo. Cover with anything that will deter them Stera... scruffy bits of branches, chicken mesh - an old net curtain...

I have had several cats over the years, jolly fond of them too! But, i love my garden and the best thing i found was gravel! Spread inbetween your plants [ also helps keep the weeds down and with irrigation] cats dont like their paws on sharpish surfaces. Good luck! Lynda

The solution is what we all know cats hate:
Rig up a sensor that detects movement in that area of your garden. Instead of attaching a light to this sensor, connect an electronic switch that turns on a water supply to a sprinkler.
No more cats, and you've got them to water the garden for you, at least for a few days :)

Not only cats but also fox used my flower bed as a toilet before, actually I saw a fox was just doing it through window! I bought powdered wolf pee from local garden center but fox was enjoying my garden just after I used it. Also cats kept coming.

I put slate, big stones and tiles to cover empty space and bamboo canes and cut rose branches around vegetable field. I gave a mulch with bark chips and gravel to hide soil in flower bed. For me it works:) I sometimes see gifts from them in my garden but not in vegetable field and flower bed!

broken slate is definatly the best with membrane .

You may notice this is a bigger problem in spring - that's because we've usually turned the soil over, which cats love. I don't find gravel or pea shingle deters them, in fact, it attracts them - they treat it like cat litter.
Jason's recommendation (PIR attached to a sprinkler) really works well, probably the best, but if you live in an area with a drought order, it won't be possible to use it right now.

You may notice this is a bigger problem in spring - that's because we've usually turned the soil over, which cats love. I don't find gravel or pea shingle deters them, in fact, it attracts them - they treat it like cat litter.
Jason's recommendation (PIR attached to a sprinkler) really works well, probably the best, but if you live in an area with a drought order, it won't be possible to use it right now.

or BROCKEN slate perhaps lol .