Trading activities in major robusta producer Vietnam remained tepid at a time when erratic weather slowed down the bean ripening process in the country's Central Highlands, while discounts stayed unchanged in Indonesia at the end of harvest season.

Farmers in the Central Highlands, Vietnam's largest coffee-growing area, sold coffee COFVN-DAK at 39,900-42,000 dong ($1.76-$1.85) per kg, little changed from 39,900-41,500 dong range a week ago.

"It's not sunny enough in the Central Highlands recently, making beans ripe slower than expected," said a trader based in the coffee belt.

"Due to the recent spike in COVID-19 cases and anti-virus measurements, there has been a huge shortage of cherry pickers. Their wages therefore have also been pushed up at least one-and-a-half times higher than the previous crop season," the trader added.

Traders said it was very likely that the harvest time would be longer, which may affect both productivity and quality of beans.

London ICE November LRCc2 futures settled up $19, or 1%, at $2,256 per tonne on Wednesday.

Traders in Vietnam offered 5% black and broken grade 2 robusta COFVN-G25-SAI at discounts of $280-$300 per tonne to the January contract, compared with last week's $250-$260 discount range.

Meanwhile, price differentials for Sumatra robusta beans in Lampung province remained unchanged this week, local traders said, amid high benchmark prices in London terminal.

One trader offered discount at $250 to the January contract, while another trader quoted $170-$180 discount to the January through February contracts.

Traders said supply remained limited, while demand was still normal.

($1 = 22,655 dong)