It began with one tree.

When we started Terra Nature, we chose the kithul palm (Caryota urens), the traditional plant Sri Lankans know and value most. It grows in the wet hills at the centre of the island, and its sap has sweetened Sri Lankan kitchens for centuries. People still ask for it by name as a healthy, organic sweetener.

Seeing how much demand there was, and how little of it reached shelves in a pure, tested form, we set out to build a range of quality foods around the tree. Necsi is that range, the first brand of kithul products from Terra Nature.

Necsi joins nectar and ambrosia, the food and drink of the gods.

Kithul doesn't grow in rows. Each palm flowers on its own time, high above the ground, and a tapper climbs to it every day to tend the flower and collect the sap before it turns. The skill passes from parent to child; there is no shortcut.

So instead of building a plantation, we went to the tapper families who already knew the trees, in the villages around Badulla in the hills of Uva. Their sap becomes every bottle of Necsi. Working with them directly is how we strengthen rural tappers, and how we keep tapping worth doing for the next generation.

• Badullawhere our tappers live and work
• One ingredientkithul sap, and nothing else

Necsi began as one bottle of treacle. Today the range is treacle, jaggery, kithul flour and Kito, our mix of kithul and tamarind. It's stocked in shops across the Kandy district and Anuradhapura, sold island-wide on Daraz, and packed for the tables we hope to reach abroad.

Our aim hasn't changed since the first tree. We want to take kithul further, and the further it goes, the more the families who tap it should earn.