Bacterial soft rot

Pectobacterium and Dickeya

also called slimy rot

The wet, slimy, foul-smelling rot of fleshy vegetables in store and in the ground: firm tissue collapses to a soft mush that stinks.

Bacterium Serious Spread in waterSpread by contactSpread by insects Spreads to neighbors

What you'll see

Affected tissue turns into a soft, wet, slimy mush that collapses at a touch.
A strong, foul, rotten smell is the hallmark — the surest way to tell it from a dry rot.
A small water-soaked spot spreads fast until a whole bulb, root or head is pulp, often leaving the skin as a bag of slime.
The rot can hollow out a stored onion, potato or cabbage while the outside still looks whole.

Why it happens

Bacteria that dissolve the tissue holding plant cells together, turning firm flesh to slime. They enter through wounds, bruises, pest damage and frost cracks, and are moved about in water, on hands and tools, and by insects.

Warm, wet, poorly ventilated conditions drive it — a wet harvest, bruised produce and a damp, stuffy store are the classic recipe.

Treating it

There is no cure; remove and bin or bury rotting produce at once so it cannot spread.
Sort stored crops regularly and pull out any soft or smelly item immediately.
Improve ventilation in the store to dry the surfaces of the remaining produce.
Do not wash produce before storing, and never store anything damp.

Keeping it away

Harvest in dry weather and let roots, bulbs and tubers dry or cure before storing.
Handle produce gently to avoid the bruises and cuts the bacteria enter through.
Store only sound, dry, undamaged crops in a cool, airy, well-ventilated place.
Control soil pests and keep beds well drained to reduce wounding and waterlogging.
Clean and disinfect storage trays, boxes and cutting knives between seasons.

Who gets it

Fleshy vegetables — potatoes, carrots, onions, brassicas, celery and stored roots and bulbs, along with fleshy ornamentals such as iris and hyacinth.