Golfers are often reminded to drink plenty of water before teeing it up on a hot summer day. Similarly, putting greens also need to stay hydrated. Typically, putting greens are irrigated at night or early in the morning. However, during periods of hot weather or low humidity, turf may need additional water throughout the day because soils can quickly dry out. Light watering during the day helps keep putting greens healthy and playing well.
Deciding how much water to apply overnight is a difficult, calculated decision that turf managers must make regularly. Applying slightly too much water can create soft playing conditions and negatively affect turf health; but playing quality and turf health will also suffer if conditions are too dry. In general, soft and wet conditions are more detrimental to playing quality and turf health than dry conditions. Therefore, superintendents tend to err on the dry side when scheduling overnight irrigation. Often, the amount of water applied overnight is insufficient to maintain optimal playing conditions and turf health throughout a hot summer day. Light applications of water during the day help turf survive by alleviating one, or both, of the following stresses:
- Drought Stress – Caused by insufficient soil moisture. Light applications of water during the day supplement overnight irrigation to provide plants with enough soil moisture to support healthy growth.
- Heat Stress – Warm-season grasses such as bermudagrass grow well in hot conditions. However, many cool-season grasses such as creeping bentgrass and Poa annua can rapidly decline during excessively hot weather. Applying small amounts of water to the turf canopy can temporarily reduce surface temperatures, cooling the turf as water evaporates. This process is commonly referred to as syringing.
Hand watering is the most effective and accurate way to water putting greens. Even with a state-of-the-art irrigation system, certain areas on each putting green will need more water than others – e.g., mounds and high-traffic areas. Hand watering provides greater control over where – and how much – water is applied, making it much easier to target specific areas. Imagine painting inside a house; a paint roller is effective for the majority of the wall, but the precision of a small brush is required for small, detailed areas. Like the paint roller, the irrigation system effectively covers large areas, but hand watering is like the brush and more effective for the details. Although hand watering is more effective and precise, it also requires skilled personnel and significant labor hours. Therefore, superintendents must strike a balance between hand watering and automatic irrigation.
Although watering putting greens during the day may occasionally inconvenience golfers; the inconvenience is worth it. Keeping turf cool and hydrated is essential for maintaining healthy putting greens that roll smooth and true.