Owner Steve McCurdy said the rise came despite heavy rain in January and February putting a dampener on tree planting and sales. It also followed a flat 2012-13 but "very quick growth" in the years prior to that.
In response, the company, based near St Albans in Hertfordshire, is building a new facility that provides tree storage. It also brings the process of rootballing and tying up trees inside on bad-weather days and provides workshop space and storage for tools and equipment.
The company recorded a 19.5 per cent rise in sales in the financial year October 2013 to September 2014. McCurdy said the growth was across the board and from big commercial developments as well as private estates, with a renewed interest in native trees.
"We've seen some significant jobs in the private sector but also in the high-end commercial sector," he added. Clients keen on the large specimen trees in which Majestic specialises include Anglian Ruskin University, Cambridge and Balfour Beatty, which wanted to hide motorway lights.
"People want to spend a bit more now to have a beautiful specimen tree," said McCurdy. "Natives are particularly in, including chestnuts, surprisingly.
"We've seen good profits and the future order book looks pretty good. We are optimistic for the next year, are investing in infrastructure but are being very careful not to get carried away."
The shed is the latest development on the 7.7ha site that Majestic bought as a bare 5ha patch of boggy land in 2000. After recording 38 per cent growth in sales in 2007, the company expanded its site by 50 per cent.