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Mold on Sphagnum Peat Moss

basket with peat image by Han van Vonno from

Gardeners who choose to use sphagnum peat moss instead of traditional soil are at risk for fungal and mold threats that will attack the growing medium. This threatens both the nutrient storage capabilities of the peat moss and the overall health of your plants. Most commonly these issues are due to storage problems and can be easily prevented.


Mold spores reproduce and grow favorably in atmospheres that are excessive in moisture and that have little airflow. The spore will reproduce rapidly on the peat moss. Mold will eat away at the moss as it grows and release chemicals that will make the moss completely unsuitable for the future growth of plants.

Mold is a dangerous fungus that can cause serious health risks to humans, plants and animals. In humans and pets, mold can cause respiratory and skin irritations that can even lead to cancer. The fungus carries various diseases that will spread to plants, stopping their development. So it is extremely important to remove mold when it is found to protect your family and garden from all of these possible hazards.


Prevention is the easiest way to keep mold at bay. This typically consists of placing the sphagnum peat moss in storage containers that are both airtight and away from moisture. Ideally, gardeners will purchase plastic containers with snap lids and keep them away from sprinklers, watering tables and the elements. Those places in particular are breeding grounds for fungal infections and molds.


Selective fungicides are a powerful combatant against molds that have already taken root in your peat moss. Before applying the fungicide, remove the infected areas to prevent contaminating the rest. The fungicide will kill off the spores without doing damage to the moss or plants that will later take root.


There are various forms of fungicide available on the market. Mostly they come in two types, selective and non-selective. Gardeners should use selective fungicides that are specific to the type of fungus that is causing problems, in this case mold. This will ensure that the peat moss and whatever plants grow there will remain unaffected by the chemicals that have been used to fight off the fungus.


Fungicides are toxic to humans and animals and are highly dangerous to small children. Keep them locked away and out of reach of where pets or kids may go looking. When using fungicides follow all of the manufacturer's guidelines, since misuse could lead to serious consequences for you or your garden.

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