Getting rid of deer or other garden pests like cats, dogs, birds, rabbits, or even the lowly armadillo can be a real challenge. Getting rid of garden pests without poisons or other harmful products just adds another layer of complexity to the problem as well.

One recent product that get a lot of favorable reviews is the Contech Scarecrow Sprinkler. This products works on almost any larger garden pests, and does it without hurting them or harming your garden or lawn in any way.

The concept of the Scarecrow Sprinkler is simple enough. We all know that if you were to spray the garden hose on almost any garden pest like a dog, cat, or bird, it would immediately move off away from the water spray.

This sprinkler takes that basic concept and just automates it. Using an ultrasonic detector (similar in concept to the one that operates the automatic lights on your outdoor garage lights), it senses the motion of pests in your garden or lawn, and shoot a short burst of water ( it lasts just a few seconds) over the area you cover when you set it up, and away go the pests. The moisture, noise and movement combine to startle your unwanted visitors away, but leaves them unharmed.

The video below shows how it worked on a spa that continually had problems with birds leaving droppings. It's battery operated (standard 9 volt battery), so you just need a garden hose to hook up to the sprinkler. One trick to setting it up right is to be sure the hose is tight in the connector, and you may want to use a little teflon tape to make sure it's water tight.

The battery on the Scarecrow is suppose to last for several thousand activations, which should be measured in months, and you can cover up to 1000 square feet (about 35 feet out from the sprinkler, with a 100 degree sensor zone).

It has been used to repel the usual suspects like cats, dogs, deer, chickens, rabbits, birds (including herons), raccoons, possums, and armadillos. I'm sure it will work on small children at times.

In fact one common complaint is that it does work, and it's easy to forget it's on and to walk into the protection zone before your remember.

Some folks claim that the pests learn to stay away after a few weeks, and you can actually move it to protect another zone while they stay away from the first one.

Check out the Amazon reviews. This works very well for a lot of gardeners, it may work for you!

Havahart has recently started shipping their version of a sonic sprayer. The reviews on Amazon seem to be relatively positive. The biggest complaint is that with very small animals sometimes the sensor isn't triggered. Overall people seem to be happy with it.