How to water of potato plants
Soil moisture can limit potato growth.
The amount of water required is influenced by soil type, temperatures, wind, and cultural practices. A general rule of thumb is to provide 1 to 1.5 inch of water weekly until just before harvest. Several critical periods need special attention.
When the vines are 6 to 8 inches tall, tubers start to develop and watering during periods of dry weather will help ensure adequate numbers of tubers. In dry years, the size and quality of potatoes can be improved by a thorough watering 1 to 2 weeks before harvest.
Regular watering throughout the season is suggested, however, to help prevent problems such as knobbiness, second growths, cracking of potato tubers, and hollow cavities in the centers of tubers.
Overwatering, on the other hand, can cause black or hollow centers in potatoes.
Drip irrigation can be used successfully with potatoes and may even lessen disease pressure by reducing the amount of moisture on plant leaves.
For a top yield you should keep your potato vines well watered during the growing season, and special during the time that the potatoes are blooming, because during blooming the plant start with the developing of the new tubers.
The best time is to water of potatoes in the morning, so that the leaves can dry up, this will prevent diseases.
As soon as the leaves are turning yellow and start to die you should discontinue watering to allow he skin of the tubers to harden off before harvesting.