Information on carrot powdery mildew has progressed rapidly since it was first observed in Australia in 2007. Disease incidence and levels have fluctuated in the carrot growing regions where the disease was first observed i.e., South Australia, Tasmania and New South Wales. The first observations were made in these states, but since then, the disease has been reported in Queensland and Victoria. This disease is going to be sporadic in occurrence, and if left untreated will cause leaf death in some instances, reducing the ability to pull carrots out of the ground. Environmental conditions have reduced powdery mildew incidence in all the states with the change from the drought conditions experienced at the time of its discovery to wetter than normal conditions. Field and greenhouse trials have indicated that the disease is controllable but not eliminated by fungicide application. Fungicides successful at controlling the disease include Amistar�, Folicur�, Cabrio�, Sulphur and Amistar Top�, the latter two having registration. Early detection of the disease is critical as control is best managed with fungicides where disease pressure is still low. In a trial, overhead irrigation reduced disease compared to drip irrigation, indicating that production areas such as New South Wales that use furrow irrigation are likely to experience more disease than in areas using pivot-applied irrigation. This has been observed in Tasmania, with the disease more severe when irrigation water was in short supply and water was therefore applied sparingly by pivot. The powdery mildew fungus spreads easily from infected to uninfected plants, especially through the movement of people and equipment. Overlapping plantings and volunteer carrots are also important sources of new infections. The temperature preferred by the fungus is around 27�C, with temperatures below 20�C and above 33�C reducing disease progress. However, infection appears to occur over a range of temperatures. This confirms that the disease is most severe in spring, summer and autumn, with periods of high and low temperatures reducing disease incidence. Varietal differences to susceptibility to powdery mildew have been identified. Information collected provides a suitable integrated management approach to powdery mildew based on variety selection, careful monitoring, and tactical fungicide sprays which are applied with the best coverage possible.