Drip irrigation for onions

Italy: Drip irrigation for onions

Onions are one of the most important vegetables in every kitchen and are thought to have originated in Central-Western Asia.

In Italy, there are currently 9,000 ha of onions producing around 272,000 tons per year (i.e. 30 tons/ha). According to 2013 ISTAT data, this vegetable is cultivated mainly in Emilia Romagna (28% of the total domestic production), Sicily (17%) and Puglia (15%).

The preferred irrigation technique is sprinkling, although drip irrigation is getting increasingly popular,. Netafirm uses it in combination with sub irrigation, where possible.

Onions can be cultivated in a variety of soils: deep with lime and alluvial sand or loamy ones.

Drip irrigation is very simple: just place a drip line more or less every two rows to make the most of the system. The same concept can be used for sub irrigation, although the drip line is placed 20-25 cm deep in the soil to irrigate the roots.

Preparing the soil is essential for irrigation to be effective. The distance of the sub irrigation drip lines depends on the width of the beds and the characteristics of the soil. This type of irrigation is mainly used when there are a lot of plants or if the number of rows per bed is odd or grouped.

The distance between the emitters and their capacity depends on the characteristics of the soil and seeding density, however they usually vary between 30-40 cm and 0.6-5 litres per hour. The Netafim drip lines advised for this type of application are Typhoon or Streamline or even DripNet for self-compensating ones.

Another important instrument for those using drip irrigation is fertigation, which enables growers to assist crops efficiently. We must consider that the roots of onions are not very deep or fibrous, so fertigation must be really efficient. 50% of the total absorption of the main three nutrients (nitrogen, phosphorous and potassium) happens during the last month before harvesting, so we must be careful about fertilising when plants really need it.

Fertigation also supplies multi-purpose compounds that contain microelements. Netafim uses this technique in the main producer countries worldwide. At the moment, productive and varietal tests are being carried out in the Voghera and Tortona area to identify the most suitable agronomic technique.

NETAFIM Italia Srl
Frazione Monleone
Via Pian Degli Alberi, 27C
16044 - Cicagna (GE)
Tel.: 0185 18720
Email: info@netafim.it
Web: www.netafim.it

Publication date: 5/8/2014