If you are about to clear out your garden, pause awhile before filling that skip. You could be amazed at the garden-related ornaments, furnishings or artefacts that collectors would be only too delighted to buy.

"Dump nothing," is the advice of Mr Joe Mullen, director of Mullen's auctioneers in Woodbrook, Co Dublin. Even if it's a granite block, it can be incorporated into a garden feature that someone will purchase.

Take three granite blocks and you have the makings of an attractive seat, he says. And collectors are often delighted to use an old zinc bath or a Belfast sink (a deepglazed pottery kitchen sink) as garden features.

At the recent annual garden sale at Mullen's, an old cast-iron hand pump fetched £280. A wallmounted trough-like bronze fountain made £1,700, while a "fish fountain" a bronze-based fountain with two bowls and glass panels made £2,600.

At the same auction, a pair of bronze cranes standing eight feet high fetched £4,500, while a set of four sandstone statues of semi-clad women in classical poses made £1,000.

Mr Campbell Armour, a director of Phillips auction house in Glasgow, concurs about not dumping things. He notes for instance that common stone feeding troughs from farms or farmsteads are "quite sought after by gardeners".

He says that even smaller troughs of carved sandstone only half a foot deep in reasonable condition can fetch £100, while larger ones can go for £500.

But beware the thief that prowls by night. Mr Armour says quite a few people decide to sell garden antiques because of thieves' attempts to steal them. For instance, a carved sandstone lion to be auctioned at the next Phillips garden sale on July 4th is being sold because "somebody was trying to pinch it". Dating from about 1900, it lies with paws extended, in length measuring three feet. Its guide price is £800 to £1,200.

A pair of terracotta or fireclay (rough glazed pottery) lions, which are almost life-size, has a guide price of £2,000-£3,000. A similar but larger pair at last year's Phillips sale made £4,200.

People who purchase or wish to retain garden features such as these often need to have them cemented in or to keep them where they are not visible to passers-by. Gardens where access is more difficult can also keep thieves at bay.

Mr Armour says the saleroom value for garden antiques can be "quite high". A carved blonde sandstone sundial standing seven foot high surmounted by a lead lion rampant has a guide price of £3,000£5,000. It too is being sold because somebody was trying to steal it.

He says furniture from Victorian (1837-1901) or Edwardian (1901-1910) conservatories like woven wicker pieces made of willow are very popular. Prices fetched depend on whether or not the design is unusual. For example a plain armchair should fetch £100, but something more elaborate like an extending chair can command £300.

Garden urns tend to fetch higher values in pairs. For instance, a pair of cast-iron urns standing eight feet tall on block plinths dating from about 1850 have a guide price in July's sale of £1,000£1,500. Two years ago a set of four cast-iron urns made £4,000 at Phillips.

Mr Armour says it's always worth checking the value of something in the garden with an auctioneer, especially if you're moving house. At the first garden sale at Phillips three years ago a bronze statue that had stood in a garden for 30 years fetched £5,000. And he advises that stone objects which are the same age as the house add to its value.