Winter is the time to use your summer-grown garlic.

Fortunately, we have great garlic-growing weather here in Western Oregon, although occasionally problems do arise. This week we are showing some common problems that can pop up and which are usually only found when you are cracking those heads, seeking the perfect cloves for your favorite potato and garlic soup.

Waxy breakdown

Waxy breakdown is a physiological condition of unknown cause. Some think it is due to high temperatures during growth, or shortly after harvest. Affected cloves are not good to eat.

Garic waxy breakdown
Garic waxy breakdown


The disease appears as irregular dark areas on the outer scales, usually near the base of the bulb. Dark blotches may form on the backs and sides of cloves within a head, which is easily rubbed off; the flavor is not affected. Red garlic is less affected than white garlic, but is not immune. This disease is more of a problem in wet years, but it does not usually contribute to decay of the cloves in our area.

embellisia on garlic

Eriophyid mite damage

Feeding damage by these microscopic mites on the garlic leads to rotting by disease organisms. The eggs, nymphs, and adults overwinter on infected garlic while in storage, and can also survive in the soil. Cutting away the affected spots can salvage the rest of the garlic.

eriophyd mites on garlic
eriophyd mite damage

Gray mold (Botrytis)

In storage, a gray mold can be seen on the surface of the bulbs or between the scales. Black overwintering structures called sclerotia cluster around the neck and between the scales.  On individual cloves, there may be extensive watersoaking extending beyond the obviously moldy area. Affected heads or cloves should be discarded and not composted. For more on this disease, see the PNW Plant Disease Management Handbook.

Botrytis on clove
Botrytis vs healthy garlic