Natural cat repellents for the garden

Spring is definitely in the air now. The sun is warmer and a little higher in the sky. The birds are back, singing and visiting the bird feeders and unfortunately, so are the cats.

Some neighbouring feline fuckeries (apologies cat lovers) have decided that our garden is the perfect spot to take their morning constitutional. Well I've got news for them.

So the other week, when Dan took Alessi to the park I embarked on a mission to make up the perfect cat deterrent.
I concentrated on two separate concoctions; one made with black pepper and the other from orange peel. Apparently cats don't like the smell of either. Fantastic.

So off I went. Boiling up pots of water, adding orange peel to one and the black pepper to the other. Then came the draining and decanting into spray bottles. The black pepper mix made me sneeze so much I thought my head might blow inside out. I took this to be a good sign.

And that was basically it. Making up the deterrents is a pretty simple game. But were they any good I hear you ask?

Well yes, it appears so! The cats used to visit the garden every single damned day. It's been just over a week now and while they are still visiting my garden, they're not 'lingering'.

I've witnessed it too. The come, they sniff, they move on. It's a beautiful sight.

A couple of points worth mentioning if you plan on making some yourself is not to bother using a spray bottle with the pepper mixture. I found that despite draining it through a muslin cloth twice, enough sediment still got through to cause problems with the bottle's pump. Which was annoying.
It's much quicker and easier to to boil up a big pot, let it cool and use a watering can instead.

Also, I've been using the deterrents every other day, but you'll need to do it daily if the weather is wet. Otherwise it'll just get washed away and you may end up right back where you started.

Someone told me yesterday that old coffee grounds can be used in the same way so I might give that go next.
What about you? Do you know of any similar natural cat deterrent recipes?