ballhead onion (Round-headed leek, Round-headed garlic)

Scientific Name: Allium sphaerocephalon

Flavour: Ballhead onions, also known as round-headed leeks or round-headed garlic, have a distinctive flavor that is pungent and slightly sweet. They possess a more robust and intense taste compared to common onions.

Growing Season: The growing season for ballhead onions typically begins in late spring or early summer, around May or June, and extends into summer, usually ending in July or August.

Native Region: Ballhead onions are native to various regions of Europe, including parts of the Mediterranean and the British Isles.

Traditional Recipe: Caramelized Onion Tart.

Ingredients:

For the pastry:

  • 250g plain flour

  • 125g cold butter, diced

  • 1 egg yolk

  • 2-3 tablespoons cold water

For the filling:

  • 500g ballhead onions, thinly sliced

  • 2 tablespoons olive oil

  • 1 teaspoon sugar

  • 2 tablespoons balsamic vinegar

  • Salt and black pepper to taste

  • 150g crumbled goat cheese

  • Fresh thyme leaves for garnish

Instructions:

  1. Preheat the oven to 200°C (180°C fan).

  2. In a mixing bowl, combine the flour and cold diced butter. Rub the butter into the flour until the mixture resembles breadcrumbs.

  3. Add the egg yolk and cold water to the mixture, and gently knead until the dough comes together. Add more water if needed.

  4. Roll out the pastry on a lightly floured surface and transfer it to a tart tin. Press the pastry into the tin and trim off any excess.

  5. In a large pan, heat the olive oil over medium heat. Add the thinly sliced ballhead onions and sauté until softened.

  6. Sprinkle sugar over the onions and continue cooking until they caramelize, stirring occasionally.

  7. Add the balsamic vinegar to the pan and stir to coat the onions. Season with salt and black pepper.

  8. Spread the caramelized onions evenly over the pastry in the tart tin.

  9. Scatter the crumbled goat cheese over the onions.

  10. Bake in the preheated oven for approximately 25-30 minutes or until the tart is golden brown and the cheese has melted.

  11. Allow the tart to cool slightly before serving. Garnish with fresh thyme leaves.

Health Properties: Ballhead onions, like other members of the Allium family, contain beneficial compounds such as flavonoids and organosulfur compounds, which may have antioxidant and anti-inflammatory properties. They are also a good source of dietary fiber, vitamins C and B6, and minerals like potassium and manganese. Consuming ballhead onions may support heart health, boost immunity, and contribute to overall well-being.

Growing Technique: To grow ballhead onions, follow these steps:

Choose a sunny location in your garden with well-drained soil.

Prepare the soil by removing any weeds and incorporating organic matter for improved fertility.

Plant the ballhead onion sets (small bulbs) or seeds in early spring, around March or April.

Space the sets or sow the seeds approximately 10-15cm apart, with rows spaced about 30cm apart.

Plant the sets or seeds about 2-3cm deep in the soil.

Water the plants regularly, ensuring that the soil remains evenly moist but not waterlogged.

As the plants grow, weed the area regularly to prevent competition for nutrients and water.

Harvest the ballhead onions when the foliage turns yellow and begins to dry out. Lift the bulbs carefully using a garden fork or trowel.

Allow the harvested onions to dry and cure in a cool, dry place with good air circulation before storing them for long-term use.