How long were they open? Potato flowers are hardly ever fertile and will just fall off after a while... Maybe a week of flowers that open and drop until they've all flowered, though the time frame is just a guess. FWIW, I have one variety that finished flowering about a week ago, and another variety that's about halfway through the flowering period, and a third variety that hasn't flowered yet.
When they flower, you can use that as sign that the potato tubers are starting to form, and about a week after all the flowers have dropped is approximately when you can dig around the base of the plants and expect to find new potatoes that you can harvest, tough you need to be careful not to break off the smaller spuds that are just developing, and, of course, doing this will reduce the main harvest of the full sized potatoes.
Last edited by applestar
on Sat Jun 19, 2010 11:17 pm, edited 1 time in total.