Some physiological disorders of cabbages

Oedema, bursting cabbages, tip burn and cold damage may cause concern but they can be prevented and managed

- Bill Kerr

Oedema is a condition that, if the farmer does not know about it, will cause instant panic. Usually the whole land will develop this disorder almost overnight and the farmer may fear that he is about to lose his whole crop from a mysterious disease.

Oedema (US spelling, edema) is caused by a sudden drop in air temperature, when the soil is saturated and warm and the sap pressure in the plant causes ruptures in cells on the lower epidermis of the leaves. It is also more likely to develop when the air humidity is high and transpiration is reduced, with water being pushed up into the leaves faster than transpiration can get rid of it. The top of the leaf shows light speckles and when the leaf is turned over, one will see a mass of small pustules. The disease is harmless and will not have a detrimental effect on the yield or the head quality.

WHEN CABBAGES BURST