Broccoli Problems
Brassica oleracea var. italica
Broccoli is a cool-season brassica that rewards consistent moisture, rich soil, and cool temperatures with a dense central head — but bolts quickly in heat and attracts a long list of caterpillars and root-zone pests along the way.
All Broccoli Problems
⚠ CriticalBroccoli — Clubroot on Broccoli
The plant wilts in the heat of the day and looks stunted and pale, with roots showing swollen, distorted, club-like galls when dug up.
⚠ CriticalBroccoli — Black Rot on Broccoli
V-shaped yellow lesions form at leaf margins, with blackened veins visible within the yellowed tissue, eventually causing the whole leaf to die.
⚠ ModerateBroccoli — Downy Mildew on Broccoli
Pale yellow patches appear on the upper leaf surface, with a white-grey downy growth on the underside directly beneath, most common on young seedlings.
⚠ ModerateBroccoli — Cabbage Worms and Loopers on Broccoli
Ragged holes appear across leaves, with green caterpillars (well-camouflaged against the foliage) and dark droppings visible on close inspection.
⚠ ModerateBroccoli — Cabbage Aphids on Broccoli
Grey-green, waxy-coated aphids cluster densely on the underside of leaves and around developing heads, causing curling and stunted growth.
⚠ ModerateBroccoli — Flea Beetles on Broccoli Seedlings
Numerous small, round holes riddle young leaves, giving them a 'shotgun' perforated appearance, with tiny jumping beetles visible when disturbed.
⚠ ModerateBroccoli — Cabbage Root Maggot on Broccoli
The plant wilts and yellows for no obvious above-ground reason, and when pulled, roots show tunnelling damage and small white maggots.
⚠ ModerateBroccoli Bolting and Flowering Prematurely
The plant sends up a tall flower stalk with small yellow flowers before forming a proper harvestable head, or an already-forming head opens into loose yellow flowers.
⚠ MinorBroccoli — Buttoning — Small Premature Heads on Broccoli
The plant forms a tiny, premature head far smaller than expected, sometimes on a stunted plant, rather than developing to full harvestable size.
⚠ MinorBroccoli — Hollow Stem in Broccoli
The main stem develops a hollow cavity when cut, sometimes with brown discolouration inside, though the head itself often looks normal from outside.
⚠ MinorBroccoli — Yellowing Leaves — Nitrogen Deficiency in Broccoli
Older leaves turn pale yellow-green uniformly while new growth stays a healthier colour, and overall plant size and head development are reduced.
⚠ MinorBroccoli — Boron Deficiency in Broccoli
Stems develop hollow or discoloured cores, and heads can show a rough, brown, corky surface texture rather than smooth, tight florets.
⚠ MinorBroccoli — Purple Leaves on Broccoli
Leaves, especially older ones, develop a reddish-purple tinge, most noticeable on the undersides and leaf margins.
⚠ ModerateBroccoli — Poor or Loose Head Formation in Broccoli
The plant produces a loose, open cluster of small florets rather than the tight, dense head expected, or heads are smaller than the variety should produce.
⚠ MinorBroccoli — Slugs and Snails on Broccoli
Irregular holes with smooth edges appear in leaves, often accompanied by silvery slime trails, with damage typically worse after rain or in the evening.
⚠ MinorBroccoli — Powdery Mildew on Broccoli
A white powdery coating develops on leaf surfaces, typically later in the season during warm, dry weather with cool nights.
⚠ MinorBroccoli — White Rust on Broccoli
White, blister-like pustules form on the underside of leaves, with corresponding yellow patches on the upper surface, and severely affected leaves distort.
⚠ ModerateBroccoli — Cutworms on Broccoli Seedlings
Young seedlings are severed at or just below the soil line overnight, often with the top of the plant left lying nearby, fully or partially eaten.
⚠ MinorBroccoli — Heat Stress and Bitter Taste in Broccoli
Heads develop a stronger, more bitter, sometimes unpleasant flavour when broccoli matures during hot weather rather than cool conditions.
⚠ MinorBroccoli — Splitting or Cracking Broccoli Heads
The tightly-packed head develops cracks or splits, sometimes exposing the florets beneath, typically after a growth spurt.
⚠ CriticalBroccoli — Damping Off in Broccoli Seedlings
Seedlings collapse suddenly at the soil line shortly after germination, with a thin, water-soaked, pinched section visible at the base of the stem.
⚠ MinorBroccoli — Thrips on Broccoli Plants
Silvery streaks and small dark specks appear on leaves, with distorted new growth in heavier infestations, most noticeable in warm, dry weather.
Broccoli Care Guide
Light, watering, humidity, fertilising, repotting and propagation — everything you need to keep your Broccoli thriving.
Full care guide →See how growers fixed these problems
Browse real Broccoli grow diaries from the community — treatments, timelines, and results.
Browse community diaries →Common Broccoli Questions
Why did my broccoli bolt and flower early?
The plant wilts in the heat of the day and looks stunted and pale, with roots showing swollen, distorted, club-like galls when dug up.… Read the full guide →
Why is my broccoli head small and loose?
V-shaped yellow lesions form at leaf margins, with blackened veins visible within the yellowed tissue, eventually causing the whole leaf to die.… Read the full guide →
What's eating holes in my broccoli leaves?
Pale yellow patches appear on the upper leaf surface, with a white-grey downy growth on the underside directly beneath, most common on young seedlings.… Read the full guide →
Why is the stem of my broccoli hollow?
Ragged holes appear across leaves, with green caterpillars (well-camouflaged against the foliage) and dark droppings visible on close inspection.… Read the full guide →
