Well-worked garden soil offers an ideal hunting ground for moles. Moles are shy creatures, so you rarely see them on the surface, but the molehills will be all too visible. A tunneling mole can burrow a distance of 100 feet in a single day, leaving ridges in flower beds and uprooting plants. Moles are notoriously hard to deter. Some people say traditional mole scarers are ineffective, but they are at least cheap and easy to try. The vibration they set off may persuade your moles to go digging elsewhere.
Mow your lawn frequently using a motor mower if you have a mole problem. A February 2009 Which? Gardening magazine report suggests the loud noise and vibrations caused by the mower may deter the moles.
Bury glass bottles up to their necks in any flowerbed damaged by a mole. Dig holes for the bottles using a trowel, placing them as close as possible to the ridge or molehill that marks the position of the mole's tunnel. The action of the wind blowing across the open mouth of a bottle sets up a vibration, which some people claim moles dislike. Move the bottles regularly to new positions so that the mole does not become used to the sound.
Push the sticks of pinwheels into the ridge left in the soil by a tunneling mole, or into the crown of a molehill. Some people claim the vibration set up by a pinwheel as it turns in the breeze is transmitted through the stick to the soil, deterring the moles. Move the pinwheels regularly to new positions so that the moles do not become used to the sound.
Plunge a wooden stake into the earth in a mole-affected area and rub the stake with the blade of a trowel to set up vibrations in the soil. A March 2010 report in Scientific American suggests this mimics the sound of a mole tunneling, prompting nearby earthworms to flee to the surface. If worms do appear, collect and remove them to reduce the moles' food supply and encourage them to forage elsewhere.
Consider setting mole traps if the vibrating devices have no effect. The Wildlife Conflicts website of Purdue University, for example, is not persuaded that vibrating mole scarers work. It suggests trapping moles is the most reliable way of controlling them.