PHOTO: Seacoast Eat Local/Flickr
August 18, 2016

There’s no arguing that the deep burgundy color of radicchio is stunning in the salad bowl, but radicchio is one of those vegetables you either love or you don’t. I find it a bit too bitter for my taste, but my husband is a big fan. To keep peace in the vegetable patch (and the house!), I grow a few radicchio plants every year for him to enjoy in salads of mixed greens.

I’ve grown radicchio in both the spring and the fall, and here in my USDA zone 6 garden, I definitely get better results from a fall-planted crop. Our spring weather is unpredictable, and a few days of warm weather in May spell disaster for radicchio—the flavor becomes even more bitter and the plants quickly bolt. But when I plant radicchio in late summer for fall harvests, the flavor is far more mild.

Radicchio is very frost-tolerant, so late-season plantings last well into November and December around here with nothing more than a layer of floating row cover to protect the plants. If I grow the radicchio in the cold frame and the weather cooperates, I can sometimes manage to harvest as late as January.

The small heads of radicchio only get to be about the size of a small grapefruit so they don’t take up a lot of room in the garden, and after a few light frosts, the flavor tends to sweeten enough for me to enjoy this vegetable right along with my husband, without the challenges of bitterness.

Planting Radicchio

radicchio
Jessica and Lon Binder/Flickr

To grow a fall crop of radicchio in colder zones like mine, sow seeds 1/2 inch deep and 1 inch apart anytime between early July and mid-August. Keep the seedbed well-watered until the plants are established, and thin the resulting seedlings to a spacing of 6 inches to give each plant plenty of room to grow.

Before sowing seeds of this and any other fall greens, I always amend my garden soil with 2 to 3 inches of finished compost to replenish the nutrients depleted by earlier crops. The increased organic matter also aids in soil water retention.

I sometimes get impatient and harvest a few baby radicchio leaves before the plants form a head. My husband enjoys these tender, young leaves in mixed salads, but most of the plants are allowed to reach maturity before harvesting.

Harvesting Radicchio

To harvest full-grown radicchio heads, I slice the plant off at ground level with a sharp knife, leaving the root stump in the ground. I then pile 3 or 4 inches of straw around the root stump to protect it throughout the winter. Come spring, I remove the mulch and the stump will often sprout a new head, resulting in a second harvest of radicchio the following year. I also do the same trick with some varieties of lettuce and I get the same results. When left in the ground, these overwintered stumps often yield the first crops of the season the following April. It gives me a head-start on spring and allows a second harvest from a single planting.



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