Smudge Pot: Oil-burning heaters used to prevent or reduce frost damage in orchards and vineyards. Typically consisting of a wide base topped by a chimney, smudge pots may be lit when frost threatens. They offer some protection by creating air currents that can disrupt settled colder air at ground level. Due to their consumption of oil and smoke production, as well as labor requirements, use of smudge pots is in decline in favor of other frost-protection methods such as wind machines and aspersion.
Frost: Subfreezing temperatures, which can damage or kill vines, are especially harmful in the early spring after budbreak. Heaters known as smudge pots, wind machines that keep cold air from settling in the vineyard and aspersion (using water sprinklers to form a protective barrier of ice around young vine buds) may be used when frosts are forecast. In the winter, before budbreak, a moderate frost can be a blessing; it hardens the vine’s wood and also kills spores and pests living under the bark.
Aspersion: The process of using water sprinklers to protect budding vines from late-spring frosts. The sprinklers are turned on just as temperatures dip below freezing, forming a protective barrier of ice that shields young vine buds from colder temperatures.