Cultivation guidelines

Cultivation of second year Quality inside onion sets

First year onion sets are cultivated from seed, and are planting material for second year bulb onion cultivation. The main reason for using onion sets for bulb production is that the crops are earlier to mature than those grown from direct drilling but there are also other advantages. For example, yields of crops grown from sets tend to be higher, the bulbs are larger, they have a higher dry matter, (which is useful for processing), and are able to establish well under poor conditions when compared to crops grown from seed.

Onion sets are also less sensitive to day length than direct drilled onions; thus onion set varieties can be used further North than the same variety grown from seed. 

In the Netherlands, onion sets can only be supplied according to the rules of the onion sets regulations, which are controlled by Naktuinbouw. These regulations are the base of the Quality Inside onion set programme.

Quality inside onion sets are kept under optimal storage conditions right up to the moment of dispatch. However, the quality of the produce will deteriorate if it is not handled correctly during loading, transport and on arrival. We advise using climate- controlled vehicles to avoid temperature fluctuations during transport which could cause condensation. Good ventilation and the shortest possible transit time are very important.

On arrival the produce should be stored in a dry, well-ventilated and frost-free storage unit, preferably in ventilated crates. It is also important to keep the period between the arrival of the sets and planting as short as possible. We also advise you to instruct the transport company/driver to check the transport documents for accuracy.

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