Key Factors for Successful Organic Lentil Production in Switzerland

Although the potential for organic lentil cultivation exists in Switzerland it is languishing at a low level. Results from Agroscope show how harvest volumes can be stabilised and whether there are organoleptic differences between varieties.

Agroscope researchers investigated how lentils can be grown more successfully than previously under Swiss organic conditions. The focus was on different lentil varieties, seeding dates, seeding densities and cropping systems. They also examined whether there were differences in flavour between the different varieties. The aim was to establish principles for more stable domestic production and determine possible consumer preferences.

Autumn sowing increases yield potential

A total of twelve lentil genotypes were field-tested over a five-year period. Yields varied significantly between years, ranging between near-total failure and 2 tonnes per hectare and year, depending on the weather. With most varieties, autumn sowing increased yields compared to spring sowing. Since autumn-sown lentils flower around 14 days earlier than spring-sown lentils, this can be an important factor in bringing forward yield formation before potential hot spells, thereby safeguarding yields. Weed pressure on the plots also plays a key role in successful implementation, particularly in organic farming.

Intercropping with oats stabilises crop stands

The Agroscope study compared the cultivation of pure-lentil stands vs. mixtures of lentil with a short-straw oat. Despite a lower lentil seeding rate, lentil grain yields in the mixed crops were not reduced because of the companion crop. At the same time, the cereals reduced lodging of the lentils which therefore resulted in more pods being harvested with the combine and in a better seed quality being obtained due to the greater distance of the seeds from the ground. Similarly, according to the experiences, weeds were effectively suppressed by the oat.

Dense stands enhance profitability

Studying the impact of stand density on yield and profitability in pure stands led to the conclusion that optimal stand density ranges between 180 and 240 plants per square metre. Although higher seeding rates led to higher seed costs, these were offset by higher yields.

Processed lentils

In terms of taste, differences between the twelve lentil varieties studied were smaller than expected. Although there were differences between the varieties in terms of e.g. mealiness or juiciness, as a whole, the differences in terms of their agronomic properties – yield, grain size and protein content – were greater.

Optimal stand density and a site-adapted sowing date are key to safeguarding lentil crop yields. The choice of a suitable companion crop has no negative effects on the lentil yield. Both seed quality and harvestability can be improved. The choice of variety should therefore be geared to market requirements as well as to local conditions. If autumn sowing is intended, then – along with winter lentils specifically bred for autumn cultivation – it is small-seeded types, and in some cases varieties from the gene bank, that appear to be promising.