How to Grow Broccolini

Quick Facts

Factor	Value
Soil pH	6 - 7
Soil texture	nutrient-rich, amended with compost or aged manure (Gardener's Path)
Drainage	well-drained
Lifecycle	annual
Edible parts	flower shoots, stems, leaves
Documented problems	4 diseases, 5 pests

At a Glance

Diseases

Powdery mildew

low

Gardener's Path names this directly: powdery mildew.

Black rot

moderate

Xanthomonas campestris pv. campestris

Gardener's Path names this directly: black rot.

Downy mildew (general)

moderate

Gardener's Path names this directly: downy mildew.

Blackleg

moderate

Pectobacterium atrosepticum

Gardener's Path names this directly: blackleg.

Pests

Cabbage looper

moderate

Trichoplusia ni

Gardener's Path names this directly: cabbage loopers.

Aphids

moderate

Aphididae (various spp.)

Gardener's Path names this directly: aphids.

Cabbage root fly (US: cabbage maggot)

moderate

Delia radicum

Gardener's Path names this directly: root maggots.

Flea beetles

moderate

Chrysomelidae: Alticini (various spp.)

Gardener's Path names this directly: flea beetles.

Slugs

low

Gastropoda (slugs, various spp.)

Gardener's Path names this directly: slugs.

Soil & Growing Conditions

Water: kept evenly moist, watered during dry spells (Gardener's Path)

Soil pH range

6 7

Span reflects genuine variation between the cited authorities, not a single agreed figure.

Growth Stages

Stage	BBCH	Notes
Sowing	0	Sow 1/4in deep, or start transplants 4-6 weeks before the last frost (Gardener's Path).
Transplanting	1	Plant out once seedlings have 6-8 true leaves, set about 1/2in deeper than their pot soil, spaced 12in apart in rows 2ft apart (Gardener's Path).
Crown development	5	Matures 60-90 days from transplanting, forming its main flowering crown (Gardener's Path).
Cut-and-come-again harvest	8	Cut the main crown with 6in of stem before flowering, then harvest side shoots for weeks after -- 3-5 harvests per plant (Gardener's Path).

Harvest & Storage

When to pick: Cut the main crown with about 6in of stem once heads form but before flowering, typically 2-3 months after planting; then harvest side shoots by cutting each stem just above a set of green leaves -- a cut-and-come-again crop yielding 3-5 harvests per plant (Gardener's Path).

Sources

1. Gardener's Path - How to Grow Broccolini

   A secondary gardening reference rather than a university or horticultural authority, used as the primary source as no university or horticultural-authority growing profile exists for this specific commercial hybrid, explicitly disclosed. A hybrid cross between European broccoli (Brassica oleracea var. italica) and Chinese gai lan (Brassica oleracea var. alboglabra), producing many small flowering shoots on thin tender stems rather than one large head. First commercialised in Mexico in 1994, rebranded "broccolini" in 1998. Full sun. Soil: nutrient-rich, well-draining, pH 6.0-7.0, amended with 2in of compost or aged manure. Spacing 12in apart in rows 2ft apart, sown 1/4in deep or started as transplants 4-6 weeks before last frost, planted out at 6-8 true leaves, transplanted 1/2in deeper than pot soil. Matures 60-90 days from transplanting. Harvest the main crown with 6in of stem once heads form but before flowering (typically 2-3 months after planting), then harvest side shoots by cutting each stem just above a set of green leaves -- potentially 3-5 harvests per plant. The entire plant is edible: curly green leaves, small florets, and long stems. Pests: aphids, cabbage loopers, flea beetles, slugs, root maggots. Diseases: blackleg, black rot, downy mildew, powdery mildew.

These source is specific to this region. The full list of 1 sources behind this guide (Gardener's Path) is in the references of our UK guide to broccolini; they describe the plant itself, which is the same wherever it grows.