Production area and history
Emilia Romagna region
This type of onion takes its name from Boretto (Reggio Emilia), its territory of origin. It is an unmistakable variety of onion for its flattened shape, with a straw-colored skin. The smallest are sought after by the pickle industry, the largest are intended for fresh consumption, as such or peeled and sold in trays.
The production of the Borettana onion (about 20 thousand tons) is concentrated in the Po Valley, especially in the Parma area. Small crops, mostly intended for industry, also exist in the Veronese area.
Borettana onion (photo www.salepepe.it)
It is characterized by a bulb very flattened at the poles, small and with straw-colored tunics and is widely used by the canning industry.
It prefers medium-textured soils, tending to loose, but also adapts well to clay soils, as long as they are fresh, deep and rich in organic matter. The preparation of the soil is very important, above all all the cultivation operations that facilitate the draining of the water (especially on clayey soils) are necessary to avoid stagnation of humidity, which predispose the cultivation to attacks of rot, in particular of Fusarium.
Sowing, understood both as modality and epoch, directly influences the size of the bulb. It is essential to use seed that is disease free and highly germinable. Germination should be checked also to better calculate the quantity of seed needed for the area concerned. The sowing depth (month of February) must be uniform: 1-1.5 cm; the distance on the row of 2-3 cm and between the rows of 8-15 cm. Germination is facilitated by a slight rolling of the ground. Harvesting takes place from mid to late July. It is also possible to plant small onion seedlings grown in an alveolar container and in a protected environment.
Onion has no particular nutritional needs. However, it requires good soil fertility and a balance between the various nutrients.
The sensitivity of the onion towards the availability of water is remarkable. This is determined by the root system which tends to occupy the most superficial layers of the soil, making the plant sensitive to water stress at every stage of its production cycle. The positive effects of the availability of water are expressed with the increase in investment density of about 35-40% and with the increase in unit production. From a qualitative point of view, the size of the bulbs grows with irrigation, decreasing the production of waste to the full advantage of the intermediate classes.
The harvest takes place when the onion leaves are withered, yellowed and curved towards the ground due to the loss of turgidity of the tissues. The traditional collection system provides for the grubbing-up of the bulb, the laying in rows, the drying in the field, the actual collection. After grubbing up, the bulbs are left in the field for a period ranging from 10 to 15 days or in any case until the roots and the aerial part are completely dry. During drying, the bulb loses about 5% of its weight. The bulb has a flattened shape, very depressed at the poles, with a concavity in the apical area, from which the leaves originate: The bulb externally is straw, with thin and paper sheaths, while the inside is white and fleshy. It has very variable dimensions, from 2 to 9 cm, but the most precious bulbs on the market are 3-5 cm, obtainable with a denser seeding and more suitable for the production of pickles and pickles.