Here is a list of 30 deterrents you could try:

1. If a Tom starts to mark his new territory you could mark over it yourself although it may surprise the neighbours!

2. You can buy repellent pellets from garden centres that smell like citrus fruits, which apparently cats don't like.

3. Or you could use the real thing lemon or citrus peels work for a bit but you have to keep replacing them every three or four days. Not good for a big space unless you really really like lemonade.

4. You could try planting Coleus Canina which emits a foul odour when a cat rubs itself against it, but I'd imagine you'd have to cover quite a large area (depending on the size of your garden) for it to be effective.

5. Lion dung is said to keep them out but it may smell even worse than cats poo, but it's good for the roses.

6. Small sticks pushed into the ground so that approximately six to 12 inches are sticking out of the ground like spikes. They must be close enough together to prevent cats snuggling their bottoms down between them to poo.

7. Get a dog.

8. Some say Jeyes disinfectant fluid around the edges of the garden works but the fluid is actually quite poisonous to cats and will kill them in fairly small amounts.

9. Spray water at them, not from a hose, from one of those spray bottles from a garden centre or use or a super-soaking water gun for cats further away.

10. I have heard that they don't like garlic.

11. A friend suggested moth balls worked for her.

12. Sprinkle black pepper & chilli around the garden, harmless to animals but an effective deterrent apparently.

13. Getting a cat yourself often works. Its very unusual for a cat to poop in its own garden, and other cats won't really come near another cats area, unless it likes them, and then it wont poop 'cos it respects the area!

14. Catch the cat and rub its nose in it (not so it smudges all over the cat, just near it) then put the cat in next doors garden, or wherever you wish it to poop from now on.

15. You can buy some pet repellent spray from the DIY stores. It is harmless to animals and children.

16. Solid toilet blocks (used in public loos usually) crumbled around.

17. Scatter citrus peel (oranges & lemons) around the garden.

18. Place pine cones around near garden borders.

19. Plant geraniums, marigolds and petunias, cats apparently dislike those plants.

20. Grow spiky plants near areas you want to keep cats away from.

21. Ask local cat owners to provide an inside litter tray for their cats to discourage outside toileting.

22. Or if the cat owner doesn't want/can't have inside trays...Ask them to dig a pit in their garden, several feet deep and 2 foot square and fill with peat. Then all that is needed is for this outside toilet to be dug over frequently.

23. If you have bare soil cover it with gravel or slate chippings etc, it will discourage digging.

24. Keep your lawn short. If you let your lawn get to 3" ish high, they will poo in it and not bury it.

25. Place a small length of hosepipe in amongst your plants, cats and birds don't like snakes!

26. Invest in a bag of coffee (grounds), and spread around the garden.

27. Plant some lavender. It works for some and smells divine and for some reason the cats hate it.

28. Olbas oil (the one you put on pillows for blocked noses) works pretty well.

29. Water 'Scarecrow' that squirts water at things it detects moving, including you!

30. If all the foregoing makes you despair then go the high-tech route and buy yourself an ultrasonic cat repeller.

They have a motion detector built-in, can be mains powered and emit a high decibel tone that only cats can here. Problem solved.

I use one at my house and found it excellent. Didn't hear any noises from it and it didn't bother the dogs next door either. I'd recommend the mains powered one rather than using batteries, they never seem to last for very long, but battery power does give more flexibility.

It has a PIR which means that it is only emitting 'noise' while the cat is in range so the cat cannot 'learn' to tolerate it. This also saves batteries (if you use them). There is an alternative of purchasing a mains connector if the battery option doesn't work out well.

They only activate when a large enough object passes by, humans included , and only go for a short time so small mammals are OK. There has been no reduction in bat activity where we live and no signs of them being mis-directed either.

The cat repeller is fantastic. Not a single cat in the garden at the moment, and when they appear they skulk along the wall and don't stay. I really recommend this investment.