Maleic hydrazide, often known by the brand name Fazor is a plant growth regulator that reduces growth through preventing cell division but not cell enlargement.[1][2] It is applied to the foliage of potato, onion, garlic and carrot crops to prevent sprouting during storage.[3] It can also be used to control volunteer potatoes that are left in the field during harvesting.[4] It was first identified in the 1940s but was not used commercially in the United Kingdom until 1984. The banning of chlorpropham as a sprout suppressant in 2019 has led renewed interest in how maleic hydrazide can be used in potatoes.[5]