Romanesco

Romanesco heads for sale at a Farmers Market.

Romanesco heads for sale at a Farmers Market.

Looking like an elaborate work of art or alien from space, romanesco is an uncommon vegetable frequently available only at local Farmer’s Markets or to grow from seed. Also called romanesco broccoli or Roman cauliflower (even though it is neither one), this unusual cultivar of Brassica oleracea dates back to the 16th century. It is sometimes mistakenly called broccoflower, but that name really refers to green-colored cauliflower. This Italian heirloom that was once grown exclusively around Rome produces striking light green heads composed of numerous cone-shaped florets, each one growing in a logarithmic spiral. The pointed groups of buds are a cluster of branched meristems arising from a central stem in a spiral arrangement, creating a fractal pattern (a self-similar pattern). The heads can be quite large, up to 5 pounds each.

Romanesco requires the same care and growing conditions as broccoli, and looks very similir to that other vegetable.

Romanesco requires the same care and growing conditions as broccoli, and looks very similar to that other vegetable.

The strap-like leaves are a dark blue green typical of broccoli or cauliflower and the plants look very similar to those other vegetables when they are growing in the garden.

This cruciferous plant is as easy to grow as normal broccoli or cauliflower. Even though it is a cool season plant, it is best started indoors 4-6 weeks ahead of time and transplanted into the garden after the last frost.

Seedling (L) and young Romanesco plant (R).

Seedling (L) and young Romanesco plant (R).

Place the plants 18-24″ apart, in fertile, well-drained soil. Keep well watered and fertilize once or twice during the growing season. Romanesco plants are susceptible to the same insect and disease problems as other brassicas, so be on the lookout for cabbage caterpillars (imported cabbageworm (Pieris rapae), diamondback moth (Plutella xylostella) and cabbage looper (Trichoplusia ni). You can cover the plants with floating row cover to prevent the adults of those caterpillars from laying eggs on the leaves, but this can be challenging once the plants get large. Other controls include regular sprays of Bt or chemical insecticides labeled for use on cole crops.

A developing romanesco head.

A developing romanesco head.

Heads should be ready to harvest 75-100 days after transplanting. Once they are ready the entire head can be cut off with a sharp knife or individual stalks can be removed. Once the head is cut it does not typically produce new side shoots. Choose dense heads without any discoloration. Harvested heads can be stored in plastic in the refrigerator for about a week.

Harvested romanesco heads.

Harvested romanesco heads.

Open pollinated heirloom varieties tend to be quite variable in the size of heads produced as well as when they reach maturity. Newer varieties offer more compact plants with more uniform head size (and usually on the smaller size) and more predictable maturity. ‘Veronica’ is the most widely available named cultivar with reasonably sized heads.

Romanesco has a mild flavor, often described as “nutty, slightly spicy” with a texture similar to cauliflower. It can be prepared in a manner similar to cauliflower or broccoli – eaten raw or cooked – but it has a different flavor than either of those vegetables. Separate the florets and steam lightly until tender. Try drizzling them with olive oil and fresh lemon juice, instead of dressing with butter. Other ways to use romanesco include mixed with other sautéed vegetables, combined with pasta in a garlic sauce, or covered in a cheese sauce.

– Susan Mahr, University of Wisconsin – Madison


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4 comments

  1. My Romanesco plants do not appear to be producing any heads yet and now it is August. I’m worried that I have all these giant plants, but will get no produce. How long should I wait before I give up? Is there a way I can trigger head production?

    • Jenna,
      I just transplanted mine 3 weeks ago, so you should have plenty of time left. Takes about 100 days to mature after transplanting.

  2. I have a dozen Romanesco growing, and they are all tipping over, as though their roots can’t hold them upright. Is that normal? Should i try to support them with something?

    • Yes, I had to support all of my romanescu’s with a stick (any straight long object will do), until they got stronger. Once they become stronger, you will be stunned at how thick and almost woody the stems get. Now, 2 months later, if I tug on the plant, it’s very, very sturdy. Nothing like the weak seedling that came out of the ground.

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