The 'Tosca' onion is a long-day yellow onion variety, recognizable by its elongated, torpedo-shaped bulbs covered with a thin, dry, glossy golden-brown skin. Its slender shape, unusual for yellow onions, makes it easy to slice into even pieces with very little waste, a valuable asset both in the garden and in the kitchen.

In the garden, Tosca stands out for its hardiness and good adaptation to cold climates. It is when the days shorten that the plant concentrates its energy on bulb formation, making it a particularly reliable variety for northern regions.

Sown early and with good support, it offers a harvest from late summer to autumn.