Is Rainwater Organic?
No, rainwater itself is not organic. However, it can contain small amounts of organic matter.
The term "organic" typically refers to substances containing carbon atoms bonded to hydrogen atoms, often associated with living organisms. Pure water (H₂O) is inorganic. Rainwater, while primarily composed of water, isn't completely devoid of other substances.
What Rainwater Contains
Rainwater can pick up various substances as it falls through the atmosphere:
- Dissolved Organic Carbon (DOC): Studies show rainwater contains dissolved organic carbon, a major component of both marine and continental rain (Rainwater dissolved organic carbon: Concentrations and global flux).
- Air Pollutants: Organic air pollutants like polycyclic aromatic hydrocarbons (PAHs), phthalate esters (PEs), pesticides, and polychlorinated biphenyls (PCBs) can be collected by rainwater (Determination of organic micropollutants in rain water for laboratory ...).
- Rooftop Contaminants: If collected from a rooftop, rainwater will contain traces of organic materials from the roof itself (Stored rainwater contains some organic matter).
Is Rainwater Suitable for Organic Gardening?
While rainwater isn't inherently organic, its purity and lack of chemicals make it a popular choice for organic gardening. It's often preferred over tap water because it is free of salts, minerals, and treatment chemicals (Rainwater Quality: 4 Reasons Plants Like Rain Best). However, the presence of some organic matter doesn't negate its suitability for organic gardening.