Maintaining a green and playable bowling green is a challenging task especially during the summer months in the UK. Proper irrigation is crucial for ensuring the health and playability of the green. Here’s a guide on how to efficiently irrigate your bowling green during the playing season.
1. Understanding the Needs of Your Green
Every bowling green is unique and has different irrigation needs based on factors such as soil type, grass type and local climate. Typically a bowling green in the UK will be composed of fine-leaved perennial ryegrass, fescues or bent grasses all of which require consistent moisture levels to thrive which we don't seem to have an issue with in the UK. During a rainless week the average green will lose about 25mm of water to evaporation and plant transpiration combined; this will be significantly higher during periods of extreme heat. This means that you should aim to replace at least 25mm through irrigation over the week. Of course you can subtract any significant rainfall the green receives from that figure. A simple rain gauge can help a lot here.
2. Timing is Everything
Early Morning Watering: The best time to water a bowling green is early in the morning. This allows the grass to absorb the necessary moisture before the heat of the day sets in reducing evaporation and ensuring the grass stays hydrated throughout the day. Morning watering also helps to minimise the risk of disease, which can be more prevalent when grass stays wet overnight.
Avoid Midday Watering: Watering during the peak heat of the day can lead to excessive evaporation meaning much of the water will not reach the roots. Additionally watering during midday can cause the grass to experience heat stress.
3. Frequency and Amount of Water
Deep, Infrequent Watering: Instead of light, frequent watering, aim for deep, infrequent watering. This encourages the roots to grow deeper into the soil, promoting a more resilient turf. A general rule of thumb is to apply enough water to moisten the soil to a depth of 4-6 inches.
Monitor Soil Moisture: Use a soil moisture probe to monitor the moisture levels in your green. This can help you determine when and how much to water, avoiding both under-watering and over-watering.
4. Irrigation Methods
Sprinkler Systems: Automated sprinkler systems are ideal for bowling greens as they provide even coverage and can be programmed to water at optimal times. Ensure your system is properly maintained and regularly check for any clogged nozzles or leaks. You can use rain gauges or even containers to check how much water is landing per square foot for example. The average automatic system will deliver 1mm of water for every 2 minutes of run time. To deliver the 25mm requirement in a week this would mean running each sprinkler for 50 minutes per week.
Hand Watering: This is useful especially in areas that may dry out faster than others. Use a hose with a fine spray nozzle to avoid damaging the grass.
5. Addressing Localised Dry Spots
Localised dry spots can arise due to soil compaction, thatch accumulation, irregular irrigation and the presence of tree roots drawing moisture away from the area.
Localised Dry Patch is a significant issue on greens across the UK. This condition causes certain areas of the green to become hydrophobic or water-repellent, preventing water absorption. To address this issue:
Firstly, the surface needs to be opened up to facilitate water penetration into the turf. This can be done using a hand tiner or a sorrel roller. Following this, it is crucial to hand water the area thoroughly, ideally with a 19mm hose connected to the irrigation system. Additional advantages can be achieved by applying a wetting agent before or alongside the watering process. It is important to regularly hand water the dry patches, allowing time between soakings to enable proper water infiltration into the soil.
To address these spots:
- Aerate the Soil: Regular aeration helps to alleviate soil compaction, allowing water to penetrate more effectively.
- Topdressing: Apply a light layer of topdressing material, such as sand or a sand-soil mix, to improve soil structure and moisture retention.
- Hand Watering: Pay extra attention to these areas with hand watering to ensure they receive adequate moisture.
- Scarification- Check thatch levels and maintain as necessary- thatch will stop your green from getting vital water, nutrients and oxygen as well as any feed or fertiliser you put down.
6. Adapting to Weather Conditions
Dry Spells: During prolonged dry spells you may need to increase the frequency and duration of watering. Keep an eye on local weather forecasts and adjust your irrigation schedule accordingly. Remember it is better to be watering deeply not daily.
Rainfall: If there has been significant rainfall reduce or skip scheduled watering sessions to prevent over-watering and waterlogging which can damage the turf and promote disease. Check moisture levels with your probe.
7. Sustainable Practices
Rainwater Harvesting: Consider installing a rainwater harvesting system to collect and store rainwater which can then be used for irrigation. This is an eco-friendly option that reduces reliance on mains water and can lower water costs. Natural rainwater has Nitrogen in too which is great for the grass!
Water-Efficient Technologies: Implementing water-efficient technologies, such as soil moisture sensors and weather-based controllers can optimise irrigation practices and conserve water.