Pineapple Heart Rot
Phytophthora nicotianae and Phytophthora cinnamomi
A water-mold disease of pineapple that rots the central growing point and the roots, causing the heart leaves to collapse and the whole plant to decline. It is the most serious disease of pineapple in wet, poorly drained ground, and it can rot suckers and newly set plants before they establish.
🔎 How to spot it
In heart rot the young central leaves fail to grow, turn yellow then brown, and the whole central whorl of leaves pulls out easily with a foul-smelling, water-soaked, soft-rotted base. Older leaves may redden and yellow with dying margins and tips. Root rot shows as stunted plants with brown, decayed roots and poor anchorage, and both phases are worst where water stands around the plants.
🥀 Damage it causes
Heart rot destroys the growing point, so the plant cannot push new leaves and either dies or is permanently set back, while root rot starves and stunts the plant. The disease is especially damaging to suckers and freshly planted slips, which can collapse before they root in, and stands on heavy or waterlogged soils can suffer heavy losses. A foul smell and a heart of leaves that lifts out cleanly mark the dead growing point.
🔬 What causes it
Pineapple heart and root rot are caused by the soilborne water molds Phytophthora nicotianae and Phytophthora cinnamomi, which need free water to produce and spread their swimming spores. Disease develops fastest in wet, compacted, poorly drained soils and after heavy rain, and is made worse by planting too deep or letting soil and water wash into the central cup of the plant.
🛡️ Prevent it
Plant on raised beds or mounds and improve surface drainage so water never stands around the plants, and avoid planting too deeply or in a way that lets soil and water collect in the heart. Take suckers and slips only from clean, healthy plants and never from diseased fields, and let cut planting material heal before setting it. Avoid low, heavy, waterlogged spots for pineapple.
🧯 If it is already here
There is no cure for a plant whose growing point has rotted, so remove and destroy collapsed plants and improve the drainage that caused the problem. Where the disease is a known risk, pre-plant dips of suckers and slips and foliar or soil treatments with phosphonate or metalaxyl-type fungicides give good protection in commercial settings. For a home grower, raised, well-drained planting and clean stock are the practical controls.
💡 Good to know
Pineapple heart rot is fundamentally a drainage problem, so the lasting fix is raised beds and good water movement rather than repeated spraying. The easy-pull heart of soft, smelly leaves is the classic confirmation that the growing point has rotted. Starting with clean suckers and slips keeps the water mold from riding into a new planting.
🌱 Plants it affects
3 plants in the library can be affected by this problem
For educational and informational purposes only. Disease management advice is general guidance drawn from university cooperative extension sources; always identify a problem positively and read and follow the label on any product before use, especially around food crops, children, and pets.