The Sumerians started a trend 3000 years ago, that the great civilisations in the arid and semi-arid regions have followed ever since. They have planted crops that have to be irrigated. The salt pans that litter once fertile lands are testament to an age-old failure to cope with salinisation, one of the main causes of the avoidable spread of desert-like conditions in the dryer parts of the world. To keep irrigating crops some countries are being forced to pump water from underground supplies. Under current practices that water will never be re-charged. In a radical re-think, farmers are now being encouraged in Israel to abandon water-guzzling crops and to plant instead species that are adapted to conditions where water supply is uncertain or running out. Prickly Profit looks at alternative efforts to nurture cactus plants which grow well in arid areas and produce a variety of fruits for sale for the export market.