With more gardeners and planters seeking the healthiest water for indoor and outdoor plants, questions arise if ultra-purified distilled water makes for an optimal choice. Distillation removes nearly all dissolved solids and minerals through the evaporation and condensation process. But is this level of purification still beneficial for plant growth and soil vitality? Let’s analyze the pros and cons of using distilled water for plants.
What is Distilled Water?
To understand if distilled water helps or harms plants, we must first examine what defines it. Distillation involves heating water to produce steam which condenses and gets collected as pure liquid water. This process strips out:
- Positive minerals but also hazardous metals and contaminants
- Microorganisms like bacteria and viruses
- Inorganic compounds
- Fluoride and chlorine compounds
The resulting distilled water contains solely H20 with 99% of other substances filtered out. Some view this as the cleanest, safest type of water. But is purity taken too far detrimental for plants?
Pros of Using Distilled Water for Plants
At first glance, the sterile purity of distilled water seems like an ideal way to hydrate plants.
- Prevents mineral build up – Plants easily absorb the neutral distilled water without excess salts, metals, or minerals. This prevents fertilizer and sediment deposits on leaves and in soil over time.
- Discourages disease – The water won’t spread plant diseases, fungus, mold, or bacteria since it contains no live organisms or spores.
- Allows adjusting mineral levels – Gardeners can add precise fertilizers or nutrients to the neutral distilled water to cater to specific plants vs trying to compensate for tap water ingredients.
- May increase shelf life – Because no microbes are present to accelerate spoiling, using distilled water for plant cuttings prior to rooting or cut flower arrangements may extend viability.
Cons of Distilling Plant Water
Unfortunately, the sterility and purity that make distilled water initially seem so attractive have downsides when it comes to plants.
- Lacks beneficial minerals – Trace amounts of minerals like calcium, magnesium, copper, and iron serve as vital plant nutrients that distilled water fails to provide.
- Can cause nutrient deficiencies – Regular use of distilled water can deprive plants of essential mineral nutrients they require to thrive.
- Impacts pH absorption – Mineral uptake relies partly on ideal pH levels. Pure distilled tests neutral at 7.0 pH which affects absorption capacity compared to slightly acidic water.
- Potential salt build up – Long term use of distilled can concentrate salts in the soil over time as plant transpiration pulls moisture but leaves dissolved solids behind.
The Verdict: Occasional Distilled Water Use Only
When weighed side by side, both the merits and risks come with using distilled water for houseplants and gardens. The answer resides in moderation. An occasional irrigation with distilled water likely causes no harm.
It may even remedy mineral and salt build up issues if they arise. But relying exclusively long term on distilled will inevitable leach nutrients from potting media. For optimal plant health across seasons, strike a balance by:
Primarily using room temperature tap water which contains trace minerals. Allow sitting out overnight before use so chlorine dissipates.
Regularly testing pH and amending growing media to keep within optimal ranges.
Supplementing with complete liquid fertilizers if signs of deficiencies emerge.
By integrating distilled water judiciously as part of a comprehensive watering strategy, plants can reap the periodic benefits of purification without sacrificing essential nutrients their structures and lifecycles rely on.