Beginner strains and how to grow them
In the northern half of the United States, the ideal time to plant radicchio in homes is from mid-June to the first third of July or approximately, Campbell said. Then it can be transplanted into the garden in July and early August.
But how do I start and with which ones?
At Uprising, Mr. Campbell and his partner Crystine Goldberg included radicchio in their crop rotation and have been selling his seeds since 2007. The varieties he recommends for beginners: Chioggia, Verona, Treviso Precoce, Castelfranco and Lusia. Within these, you can select varieties that are rated for earliness – short-season varieties whose descriptions say 60 days to ripeness.
In Veronas, for example, the varieties can range between 55 and 120 days, with the days to maturity counting from the time the radicchio is transplanted into the garden. Choosing those with shorter maturities minimizes the risk of encountering harsh weather transitions at the other end, even though they are sweetened by the cold.
Radicchio can be sown directly, but Mr. Campbell recommends sowing it indoors about four weeks before the transplant date instead, as the summer soil can be hot, dry, and hard to germinate and it is easier to weed around grafts, as it is near small, emerging seedlings. Place the grafts like you would on a regular lettuce, he said, maybe 10 to 12 inches apart.
Radicchio has few disease and pest problems. Voles love the big roots, however, and deer apparently got the memo that radicchio is trending too. The riot team found out the hard way when a quarter acre of heads disappeared into a field deer had never visited before.