Aphids feed on new shoots and buds. As a result plants may wilt, look distorted and curled. Aphids also act as vectors for a number of viruses, causing even greater damage. There are several different types of caterpillars that attack brassicas. Large and small cabbage white butterflies, diamond back moth and the green looper are common. Both snails and slugs are attracted to the delicate and crisp leaves of brassicas. They can eat whole young plants and can severely damage older plants. The greatest damage occurs during mild and damp weather. Flea beetles, wireworms and cutworms can all damage developing seedlings.
Any cuts, bruises or damage will provide an entry point for disease and lead to down-grading of the produce. Failure to keep the crop clean can leads to a wide range of decays in store. These include watery soft rot (Sclerotinia), grey mold rot (Botrytis cinerea), alternaria leaf spot (Alternaria spp.) and bacterial soft rot (caused by various bacterial species including Erwinia, Pseudomonas, and Xanthomonas).
Controlled atmosphere storage is increasingly practised to maintain quality in store over longer periods and extend the marketing period. However, compared to other vegetable crops, cauliflower and broccoli in particular are extremely perishable and should be stored for relatively short periods.