Watering a pomegranate plant is important if you want optimum fruit production. How much or little you water will depend on several factors including how much rainfall occurs and soil type and drainage. Pomegranates can stand very dry air conditions but, to produce good fruit, they need some moisture in the soil. In general, when growing on loose, sandy soil pomegranates will require more water and more fertilizer. When growing in heavier clay-based soils that retain more moisture plants won't require as much moisture.
On average, pomegranates require about 45 inches of water per year either from rainfall or irrigation. For those of you who live and grow fruit plants in the Southeast US and other areas that recieve on average more than this amount, you don't need to worry too much about having to provide supplemental water.
Pomegranates are drought tolerant plants. That being said, during prolonged periods of dry weather the fruits will suffer and will either fall from the tree or be very small if there is little or no supplemental irrigation provided to compensate. If for some reason you cannot water during dry periods don't worry too much, the plants should survive. Just don't expect as much fruit.
Watering during the spring and summer...
During the spring and summer, keeping your soil moisture at a constant level will help produce the best fruit size, color and taste. This is not an absolute figure as soil type and air temperatures can make a difference. Too, it depends on when rainfall occurs in a certain region. If there's sufficient rain during spring and eary summer the need for supplemental irrigation is lessened, but some water will be needed if the weather during summer turns very dry. On the other hand, during seasons when there is abnormally heavy rainfall, or plants are overwatered, fruit production and quality can suffer or roots can develop rot, which can be detrimental to the plant. That being said, where I grow pomegranate here in mid Georgia we've had exceptionally rainy seasons with no injury at all to plants. Pomegranates, like many other fruit bearing plants and trees, just don't like constantly wet soil. Fruit splitting is a problem if too much water is received by the plants after the fruits start to ripen. That's why it's best to plant them in well-drained soil, or raised beds, and provide water to keep the soil moist when necessary.
When and if there is a dry spell, and there's a need to irrigate, it's best to give the plants a deep watering at longer intervals and less frequently than to just provide a splash of water every day.
Watering during the fall...
Too much water in the fall, when fruit is ripening, can cause fruit splitting as well. The idea is to maintain even soil moisture throughout the fall season as in the summer. But, with cooler fall temperatures there usually isn't the need for as much water.
Watering during the winter...
During the cooler months of fall and winter there won't be much of a need for any supplemental irrigation. Pomegranates actually like dry winters. Though, if a deep freeze is forecasted, and there hasn't been any recent precipitation, it's a good idea to provide a good deep soaking to the plant. This way, the water in the soil will form ice around the roots insulating them at 32 degrees F, which any variety of pomegranate can handle without experiencing any damage.
Other helpful pomegranate watering tips...
- When it comes to water just remember that pomegranates like moist, not constantly wet, soil.
- Drip irrigation is the best way to water pomegrantes as it maintains the soil moisture level that pomegranates like.
- Hand watering plants using the deep soaking method works fine as well.
- Overhead irrigation is the least desirable method but will work. Try not to use this method when the fruit are ripening because it can make the fruit split. One advantage of sprinkler irrigation is that it can help prevent damage from a late frost in spring that occurs when there is new, tender growth on plants.
- Spraying diluted Calcium Hydroxide after the fruit have set has shown to be helpful in preventing fruit splitting in regions where this might be a problem.
Happy pomegranate growing and eating!