Pests and Diseases
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  • White Rot:  Soil borne disease. Usually found where land over-cropped with members of the onion family. No known cure at present.

  • Virus: Onion Yellow Dwarf is the main one involved but stocks may harbour up to three or four other viruses. At worse plants are killed, at best some stocks are capable of carrying certain virus without showing the symptoms. Most commercial stocks contain at least some virus, although ADAS are multiplying virus-free stocks currently.

  • Penicillium attacks bulbs (and cloves) in store readily. The slightest bruising or mechanical damage allows disease entry.

As with herbicides, materials approved for use on onions may be used on garlic. Additionally there are a few    specific off-label approvals for garlic for aphid, thrip and cutworm control. All off-labels are at Growers risk and all relevant safety precautions must be followed.


Harvesting begins in late July. Bulbs required for market should be harvested as soon as the top leaves turn      yellow. If lifting is delayed, quality will quickly deteriorate especially if the weather becomes wet. The skins are  subject to staining once the bulbs are mature. High temperatures are required for ripening. Growers either lay the bulbs out in glasshouses or open, rain-proof sheds. Excellent quality has also been obtained by following the same procedure as for drying bulb onions after harvest. Providing they are left very dry, bulbs of late varieties will store up to 6 months at ambient, beyond this it is suggested bulbs are kept for a further two months at 0.5ºC.