I planted potatoes in pots on my balcony. They are now over a metre and a half high but have not bloomed. There are 5 plants, only one has had 3 blooms. I planted them in July. They just won't stop growing. Is there a problem?
It sounds to me like you're potatoes are getting a lot of nitrogen. This promotes a lot of growth, but it doesn't encourage flowering. Still, it shouldn't be a problem. According to the, "Potato Association of America Handbook: Introduction," (http://www.umaine.edu/PAA/ )flower production isn't necessary for potatoes to produce tubers, although they often coincide because of environmental conditions.
"...Contrary to a commonly accepted notion, tuberization is not dependent upon flowering. Potato plants will form tubers without any flowers ever appearing on the tops. Some researchers have suggested that tuberization is actually enhanced by removing the flowers or flower buds. The notion that tuberization depends on flowering arose because unfavorable climates such as hot and dry growing conditions, which are normally unfavorable for flowering, also retard or even inhibit tuber formation. Because climatic conditions that favor flowering also favor tuberization, it seems natural to make the mistake of associating flowering with high yields and poor flowering with low yields..."
As you can see, you can still expect some tubers. You might see lower than normal yields due to growing conditions, but not because your plants are failing to produce flowers.
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