Why Isn't My Broccoli Producing Side Shoots After Cutting?

One of the best features of calabrese and sprouting broccoli is their ability to produce a succession of smaller side shoots after the main head is harvested — extending the cropping period by many weeks. When these side shoots fail to appear, or are sparse and quickly flower before they are worth cutting, the plant is usually short of nutrients, under water stress, or the variety has simply run its course for the season.

Not feeding after cutting the main head

After cutting the central head, the plant needs a significant amount of nutrients to fuel side shoot development. If no fertiliser is applied, the plant draws on reserves that are often already depleted from head production. Apply a balanced general fertiliser or liquid tomato feed (high in potassium and phosphorus) within a week of cutting the central head, and repeat every two weeks. This single step dramatically increases side shoot quantity and size.

Wrong cutting technique

Leave 10–15cm of stem below the cut — this length of stem provides the base from which side shoots develop. Cutting right at the base removes many of the potential shoot nodes. Cut at an angle to shed water and reduce rot at the cut surface. Do not remove outer leaves unnecessarily as these continue photosynthesising and supplying energy to the side shoots.

Variety differences

Not all broccoli varieties are equally productive for side shoots. Single-head calabrese varieties bred primarily for a large central head may produce few or small side shoots by design. Sprouting broccoli — the purple or white type grown over winter and harvested in spring — is bred specifically for abundant side shoot production. If side shoot yield matters to you, choose varieties specifically described as side-shooting or sprouting types.

End of the productive season

All broccoli eventually reaches the end of its productive period and begins to put all energy into flowering and seed production rather than vegetative side shoots. The shoots come faster, smaller and flower more quickly. When shoots are only a few centimetres long before flowering, the plant has finished. Remove it and compost to free up the bed space.