What to do with overwintered brussel sprout plants?


I am in the process of prepping the raised beds I built last year. I grew some brussel sprout plants(planted too late) that grew small, marble sized sprouts that have survived the winter and are still quite green. The stalks are 18″ or so. I’m thinking I should slice them off the stock but should I cut the plant down to the ground for growth this year?
Thank you.


Thank you for contacting Toronto Master Gardeners. I am sure your question will be helpful to other vegetable growers too.

Brussels sprouts (Brassica oleracea var. gemmifera) are considered biennial meaning that their life cycle is two years long. They produce sprouts in the first growing season (provided they have enough time until harvest, typically 80-100  days) and flowers and seeds in the second growing season. They are one of those unique plants where harvesting occurs in the fall and into winter – and in fact the sprouts taste sweeter after a frost or two!

This article from Busy Backyard addresses your question directly. Despite being biennial, many gardeners treat Brussels sprouts as an annual and plant them each year. If you leave the stalk in the ground after harvesting, the plant devotes its energy in the second growing season to producing flowers for pollination and making seeds, rather than growing the sprouts that gardeners want to harvest. If you continue to harvest individual sprouts (rather than the entire stalk) and if the temperatures don’t get too cold (below -10 degrees C) plants may continue to produce sprouts through the winter. But in the second year, the plants transition to making flowers.

In addition to the long timeframe required before harvesting, Brussels sprouts need a minimum of six hours of sunlight per day, regular watering, staking when they get top heavy, and removal of the yellow leaves as soon as you see them appear. They also require mulching in the fall to protect the plant from frost so that it continues to produce sprouts for as long as possible. Harvesting sprouts once they are 2.5 – 5.0 cm in diameter will give you the best tasting sprouts (any larger and they can be bitter) and will encourage the plant to continue producing sprouts. More growing recommendations can be found in these links to Cedar Circle Farms and Education Center and Homes and Gardens.

Your decision about whether to remove the sprouts and cut back the plant really depends on what you want your garden to produce this summer. If you are curious about what the flowers will look like then leave the stalks to continue to grow. If you are more interested in an annual harvest of sprouts, then beginning new plants each year will be the better decision.