Your neighbor’s potatoes are in full bloom while yours don’t even show the slightest bud. Are they just late or have you made some monumental gaffe? Does this mean your potato harvest will be a failure?
Just relax! Flowering is not required at all for potatoes to produce tubers. Some varieties bloom readily, others rarely, others not at all (at least in northern regions) and whether they do or not changes nothing about the harvest. It’s largely a question of variety, although the environment is also a factor. But for whatever the reason, it really won’t affect your results.
In a similar vein, some years certain potato varieties produce not only flowers, but also small green fruits and other years, not at all. Read A Garden Mystery Explained: When Potatoes Produce Tomatoes! to learn know why.
Some gardeners rely on their potatoes blooming to tell them when to harvest new potatoes, because usually when they bloom is also when the plant first begins to produce tubers. So when their plants don’t flower, they’re not sure when to harvest.
If that’s your problem, just take a gander at your neighbors potato plants. When their potatoes have been in bloom for a week or two, dig into the ground at the foot of one of your plants to see if the tubers are of the desired size.
Note that new potatoes don’t store well, so only harvest enough for your immediate needs.
The Main Harvest
As for the main crop, you’ll know its time to dig them up when almost all of the the leaves have turned yellow. Under good conditions, you can store mature potatoes all winter.