Potatoes like routine and consistency. They like their soil at a consistent moisture, for a total of about two inches of water a week. Too much water—or too little—and you can look forward to growth cracks, hollow potato centers, or weirdly shaped spuds.
What’s a gardener to do? Get a rain gauge. If you put a rain gauge right near your potato plants, you can see exactly how much water they’re getting and then you can plan accordingly. Expect to do a lot of watering when the potato plant foliage is fully developed—from late June to early August. This is when the plant flowers and the foliage turns dark green.
Now, this may sound counterintuitive, but when the mature potato plants start to turn yellow late in the summer, don’t panic. It’s not you, it’s the potato letting you know the tubers are developing. You can cut down on your watering, which will send the plant energy to the tuber, where you want it.
Sweet potatoes love water after planting and as they grow—about an inch of water a week is enough. As the season goes on and the plants mature, you’ll actually want to cut back on watering to keep the roots from cracking.
How often do you water your potato and sweet potato plants? Do you use a rain gauge to keep track of the water the plants receive. Please tell us how you ensure that your potato and sweet potato plants get the right amount of water.