Keep the heads clean and free of soil and mud. Ideally, radicchio has a spicy and mildly bitter taste. A strong bitter taste, and toughness, develops if harvest is delayed or if crop is over-mature, and then the product become unmarketable. Specialty leaf lettuces, spinach, and mustards for bag mixes have usually been harvested by hand, but harvesters for this use are now available. A picture of the machine can be seen in Johnny's Select Seeds 1998 catalogue, page 87.
Leafy items are extremely perishable and needs to be handled delicately, and marketed rapidly.
If the plants are wet with rain or dew the leaves are more brittle and break more easily. Leave a few undamaged wrapper leaves on each head. Grade heads according to size, pack in cartons. Precooling is best done by vacuum cooling because it is more effective and rapid than hydrocooling. Also, since most radicchio is field packed in corrugated cartons, vacuum cooling is more suitable.