The article highlights the high demand and prices of Hau plums in Vietnam, particularly in Hanoi and Ho Chi Minh City, at the start of the season. Despite the high retail prices ranging from 120,000 VND to 150,000 VND per kilogram, farmers in Son La are selling the plums at much lower prices, with the price fluctuating based on the quality. The article also mentions that the plum season in Son La extends from April to July, with an expected production of 88,000 tons this year, a increase from last year. Additionally, it was mentioned that post-ruby plums from Son La were exported to Singapore and Malaysia last year.