Protecting Blueberries from Heat Waves

It is well known that in the months after blueberry harvest—July through October—the plant builds strength, develops flowering shoots, and forms flower buds on them. A successful completion of this process determines the abundant yield of the following year.

In blueberry production, high temperatures in July–September (>28°C) and hot winds interfere with this process. Using shade nets under the high-humidity conditions of Western Georgia will lead to disease problems.

In this situation, an overhead sprinkler (rain) system can help. Moreover, you can use the same system in spring for frost protection, and at the same time cool the plants in July–August–September. Our sprinklers operate at low pressure, so there is no need to create an additional irrigation system; they will connect to the drip system pipeline. The sprinklers do not work with an impact mechanism, so their supports can be inexpensive stakes. See the videos: YouTube 1, YouTube 2.

For 1 hectare, 100 sprinklers are sufficient, and the budget is not large. A more detailed system description can be found here: Frost problems in blueberries and Frost protection and cooling system in blueberries.

There is a methodology based on weather-station data that determines when to start and stop cooling. This methodology calculates the level of plant overheating. Alternatively, you can use a leaf-temperature sensor and connect automation to its readings. Based on this, the sprinkler system will switch on and off at the required time. Practice shows that during the hottest hours, running it for 15 minutes per hour is enough to cool the plant.