The Cardiff-based firm, which grows leeks in Flintshire, north Wales, said this year's improved growing conditions have enabled harvesting to take place four to six weeks earlier than last season.
During the peak of the leek season - officially starting this month - the firm delivers up to 40 tonnes of leeks a week to its main customer, Tesco. The first batch was sent to the supermarket depot last week.
Brand manager Rhiannon Williams told Grower: "Last year we were pumping water off the fields in horrendous conditions. This year it's not been a great August but the conditions are much better than last year and, in terms of their size, (the leeks) are a lot nicer this year."
The company, which also grows cauliflowers and daffodils, is celebrating this year's leek season by holding a Welsh leek festival in Cardiff during the last week of October.
The autumn events follow on from the success of the firm's St David's Day celebrations earlier this year, when its leek mascot Carwen was used to promote its produce.
Other leek growers in the country are also expecting higher yields. Mervyn and Marilyn Casey, of Willow Farm in New York, Lincolnshire, said: "Last season the cool, wet weather in June and July held the crops back enormously and we were looking at very low yields.
"There was a shortage, and the problems were reflected in the crop right throughout the winter, with much lower yields than would normally be the case.
"This season we have had a pretty reasonable summer with fairly good growing conditions and yields and an earlier crop. Going forward, I think there's potential there for pretty normal yields and sufficient crop for the market - but what sales will be like, I don't know. We are now into the second year of our PR campaign and have had quite a lot of success with it. We think that sales are climbing as a result."
David Edge of Riccadonna Produce in Preston, Lancashire, said that poor weather made leek growing in his part of the country quite difficult.
Meanwhile, the British Leeks campaign - a PR initiative started a couple of years ago by the Leek Growers' Association - is about to get a revamp. Representative Kate Kerss told Grower the campaign is set to get a new theme and website in the coming weeks.