This succulence enables the species to survive in areas of low natural rainfall, making it ideal for rockeries and other low-water use gardens.
Most species of camellias also require a large amount of water, either from natural rainfall or from irrigation, and the plants will not tolerate droughts.
Salinity from irrigation can occur over time wherever irrigation occurs, since almost all water (even natural rainfall) contains some dissolved salts.
For example, it does not make sense to grow tomatoes in Arizona because there is not enough natural rainfall for them to survive without constant watering.
This was not a problem in temperate England, where the concept of the lawn originated, as natural rainfall was sufficient to maintain a lawn's health.
In many Old World wine regions, natural rainfall is considered the only source for water that will still allow the vineyard to maintain its terroir characteristics.
Depending on the climate and amount of natural rainfall, areas with poor water retention may need irrigation.
However, in the United States only 5-15% of the water required for corn comes from irrigation while the other 85-95% comes from natural rainfall.
Some foggy neighborhoods in Lima, Peru are using "fog nets" to harvest moisture as an alternative to scarce natural rainfall.
Archaeological investigation has identified evidence of irrigation where the natural rainfall was insufficient to support crops.