Those large green heads of broccoli familiar to most of us are actually newcomers to the vegetable world. Broccoli looked a lot different before plant breeders in the mid-twentieth century selected for large, uniform heads suited for commercial production. The parent plants of modern broccoli produced many small shoots, rather than a single head. Many varieties were also biennial and required a cold treatment, or vernalization, before making sprouts.

In England, heirloom sprouting broccoli varieties have increased in popularity in recent years. Traditionally planted in late summer, they grow very slowly during the winter months. When temperatures start climbing in February, the plants start to grow again and produce prolific amounts of small purple florets on long, bright green leafy stems. Unlike broccoli rabe or rapini, the shoots are mild-flavored, even sweeter than typical broccoli. These shoots are harvested from March to May, when other fresh local vegetables are in short supply and high demand.

So if it can grow in England, why not in New Hampshire? Our winters are more severe than those in England’s mild maritime climate, but Dr. Becky Grube, UNH Cooperative Extension Sustainable Horticulture Specialist, thought these varieties might do well here if given a little protection.

To cope with a short growing season, many of our farmers and gardeners already create warmer climate zones by constructing low-cost, unheated greenhouses (called high tunnels) or cold frames. Grube’s research results this spring? Delicious! She has shown that purple sprouting varieties can overwinter successfully in unheated greenhouses in Durham and produce very early spring crops. She is evaluating which varieties do best here, and what growing practices are best for the crop. Most taste-testers are eagerly waiting for more shoots.

Currently, seeds of these varieties are available from only a handful of companies (Thompson & Morgan, Bountiful Gardens, to name a few), but Grube expects that to change as their potential here is demonstrated (and New Hampshire growers clamor for more seeds.)

Shown in the photo are Purple Sprouting Broccoli 'Claret' overwintered in a tunnel, ready for harvest in April.