300 seeds. 85-100 days. Cichorium intybus. Biennial.
 
Radicchio 'Rossa di Treiso' has green leaves in summer that turn wine red in autumn.  This non-heading variety of raddichio is bitter with a crunchy stem. I like to use it as a winter forcing variety as the bitterness becomes milder. To force it, cut off most of the leaves and dig up the roots in autumn. I keep my plants in a little pot in the basement where it will quickly produce thick red leaves to add to salads and stir-fry. Grilling and cooking it will mellow the bitterness. Heirloom from Treviso, Italy.
 
To save radicchio seeds, overwinter the plants in the garden. The next year, the plants will send up 4-foot flower stalks covered in blue flowers which will turn into seed heads.
 
Spacing 7 inches.
 
Sowing Raddichio Seeds: 
 
Sow oudoors in spring to early summer, 1/4 inch deep. Thin to 7 inches apart. Best grown in cool weather.