Most of the 900 staff at vitamins maker Blackmores have been given an extra six weeks' pay as part of a profit-sharing scheme, while investors enjoyed a 63 per cent rise in the final dividend to $1.35 a share after booming Asian demand fuelled a profit bonanza.

Blackmores chief executive Christine Holgate told Fairfax Media on Tuesday the profit is set to go higher still, but is being held back by supply constraints in some raw materials that go into products such as evening primrose oil and vitamin E cream, with the company carefully managing its supply chain so it doesn't compromise quality.

Blackmores doesn't expect to match last year's record full-year performance. Credit:John Woudstra

"We have been constrained. That is the reality. Some raw materials are only grown and harvested once a year," Ms Holgate said, referring to the herb that goes into Blackmores' hugely popular evening primrose oil.

Blackmores sold 35 million bottles of vitamins, oils and other products during 2014-15 across its product range, which stretches to 500, with high-strength fish oil one of the biggest sellers.