Ultrasonic devices emit a high frequency sound which is annoying to cats (and dogs) but is not audible to humans. There are various different models some of which operate continuously and others which have an infra red detector and only emit a pulse of sound when cat triggers device. To be successful you need to ensure that model is powerful enough to cover area you wish to protect. In addition make sure that sound frequency is designed for larger animals since some models are intended to deter insects and so would be no use for cats.

There are also commercial scent cat repellents. Those that use chemicals should be kept away from any food crops but essential oil based granule varieties act in same way as orange and lemon peel mentioned above. Another way to keep a cat out if garden is a repellent evaporator which consists of a container holding puffed rice which has been impregnated with essential oils. These are effective for three to four weeks and can then be refilled for a further period. Another natural product which many people claim really keeps a cat out of garden is lion's dung. You may need to visit your local zoo to obtain this although some stores do stock zoo poo.

In Ontario, Canada local township provides a cat trap service. Once animal enters cage it cannot escape but is completely unharmed. The owner has to pay to recover his pet and so should be encouraged not to let cat stray in future. Apparently few owners bother to reclaim their cats but just obtain another kitten. However this sounds like a good way of dealing with a cat that cannot be deterred by any other method. If there is no such scheme in your area, just buy your own trap.

So, to recap, first priority is to secure your boundary fences. Then you have whole selection of suggested cat repellents ranging from homemade recipes to expensive commercial gadgets. I would suggest that you try orange peel and prickly twigs for a start. If you are around when intruder appears, try bucket of water or hose. Even if you miss, shock may be a sufficient deterrent. If these do not do trick, then you may have to consider commercial alternatives.

Hugh Harris-Evans is a retired 62 year old who divides his time between building his gardening web site http://www.garden-supplies-advisor.com and getting his hands dirty in his real world garden.

This inspiration was first published in A Daily Dose of Happiness: ( http://www.thehappyguy.com/daily-happiness-free-ezine.html ), to which one subscriber commented:

"Another thought is, do dishes, laundry, sweeping, dusting, and other chores as a family. The best conversations I ever had with my parents, grandparents, and other family members were when we were doing dishes or laundry, etc. TOGETHER!"

To that, I had to laugh...and respond: "Indeed, folding laundry is what passes for going on a date in our house!"