Brussels sprouts are planted in nursery flats in the late winter, from January through May, and spend the first 50-60 days of their lives at the nursery.During this time, the fields are prepared for transplanting by dicing and plowing. The fields are fumigated prior to transplanting with Vapam or Telone to prevent nematodes from damaging the crop. The sprouts are then transplanted into the fields on 36-inch beds at spacings of 13-16 inches apart.
They are cultivated several times to prevent weeds from taking over, and are irrigated every 3-4 weeks during the growing season by overhead sprinkler or drip irrigation. They are sprayed with pesticides as necessary to prevent aphid and worm infestation. Several newchemistries have been developed in recent years, allowing growers to reduce the use of organophosphates and replacing them with things like Admire (R), which was developed by Bayer Crop Sciences. The active ingredient is Imidacloprid, the same thing found in Advantage (R), the drops you put on your pets back to prevent fleas for a month at a time. Sprout growers can apply a mere 16 oz per acre, which is shank injected into the soil during sidedressing for 90 days +- protection from the cabbage aphid, our biggest pest problem. Several new controls for worms have also been developed using chemistries that affect the physiology of the pest but are fairly innocuous for humans. For an excellent compilation of pests and remedies for Brussels sprouts, including photos, check out the UC Pest Management Guidelines.
The sprouts are “topped” 50-60 days prior to harvesting by machine; the terminal bud is pinched out by hand to prevent the plant from growing taller and to send the plant’s energy into the development of the Brussels sprouts. The sprouts form at the base of each leaf petiole, in a spiral along the stem, where 80-100 sprouts per plant yield 2-2.5 pounds of sprouts per plant. The plant itself grows from 2.5 to 3.5 feet tall. Just prior to harvest the leaves are cut off by hand with a machete (large knife). The plant is then cut off at the ground and fed through a stripping head, which removes the sprouts from the stalk. The stalks remain in the field and the sprouts go on to a cleaning shed, where they are cleaned and sorted, then sized and sent on to our packing facility. The smaller sprouts, 3/4″ to 1.25″ in diameter, are sent off to the processors for freezing, and the larger sprouts are cooled, sorted again, and packed for shipment to the fresh market.