The Best Water for Your Plants: How to Choose and Use the Right Water for Optimal Plant Health

Household plants have continued to grow in popularity across the world. They have made their way from several decorative additions in the front lawn and back garden to establishing their presence amid modern interior design. Not only do they have a certain aesthetic appeal, but they also offer a range of health benefits, including introducing purified air, reducing pollutants, and even helping to reduce stress levels.

Given their place in our homes, they need to must receive the proper care to flourish and continue to improve our lives. Like humans, plants need a consistent supply of clean quality water to grow, but this isn’t as easy as simply filling up a bottle from the kitchen sink and pouring it over the leaves. 

After all, not only can too little water kill plants, but so can too much water and this in fact is over-watering can , too, and is actually the leading cause of houseplant death, given the way how it prevents oxygen absorption. What’s more, when watering plants, it is bestessential to water the soil, many plants dislike their leaves getting wet and then rotting.  Some plants prefer to be watered at the base to aid the water in reaching the roots not the leaves to prevent rot, and to water the plants at the base, as this will help the water reach the roots. To avoid shallow root growth through frequent watering, it is best to water plants once a week.  For amateur plant lovers, the best investment you will ever make is a water meter from your local plant shop.

Water quality is also crucial. For example, it helps to avoid too cold or too hot water, as this can damage the plants. And then, there are many different types of water quality that can be used for plants, including rainwater, distilled and purified water, and tap water.

In this article, our team at zazen Water explores the best water for outdoor and indoor plants, including water quality, whether purified and filtered is good water for plants, and much more.

Water Quality and Plants

Water is absorbed through plants’ roots, either through the it is leaves or, more commonly, through the soil. The water then passes through its vascular system into stems, buds, leaves, flowers and even their fruits or vegetables, just like it would in the circulatory systems of our bodies, sent through to our organs, muscles and tissue.

The drinking water destined for human consumption is somewhat filtered, but there is the potential for contaminants and chemicals to be present that can lead to a range of adverse health impacts, such as chlorine, arsenic, pathogens, and even microplastics. The same is true when this contaminated water is given to plants. In fact, many plants are even more sensitive to elements like fluoride and sodium.

What is the Ideal pH Level for Plants?

The soil’s pH level is also important for optimal plant growth. This is a scale referring to a level of acidity and alkalinity ranging between 0 (highly acidic) to 14 (highly alkaline), with 7 being a neutral balance. The human body typically ranges between a pH level of 7.35 to 7.45 to be slightly more alkaline, whereas soil is often more beneficial at levels below 7.0. It largely depends on the type of plant, but examples include blueberries, azaleas and rhododendrons thriving in acidic soil between 4.5 and 5.5, and roses performing best in a more neutral pH of 6.5 to 7 pH level.

Different Types Of Water and Their Effects On Plants

Tap Water

As mentioned above, tap water is treated with chemicals to make it safer to drink, but there are chemicals present that can harm plants. Chlorine and fluoride are two common chemicals found in tap water that can damage plants. So, you’re likely wondering how to make tap water safe for plants? Well, if you use tap water for your plants, be sure to let it sit out for 24 hours before watering them so that the chemicals have time to evaporate and dissipate. You can also utilise an at-home benchtop water filter like the zazen water system..

Rainwater

Rainwater is the purest form of water for plants. It’s free of chemicals and other pollutants that can damage them. Rainwater is acidic and does not contain the essential minerals that spring water and river water contain.  Rainwater falling directly on your garden plants is of course beneficial, but the health of the plants then depends on the health and state of the soil they are growing in.  When your plants are bound in pots, they are reliant on you for all their needs and using just rainwater will not deliver the range of nutrients they require for abundant growth and health.  In this scenario you need to consider the level of minerals in the soil and you can improve this using water heavy with minerals or add mineral dust to the soil as you would fertiliser.Unfortunately, not everyone has access to fresh rainwater (especially when their houseplants are located indoors), and rainwater left sitting in a tank can collect sediment and harmful parasites, which in turn hurts the plants.

Filtered Water

Filtered water has been passed through a filter to remove impurities. This type of water is usually safe for plants, but depending on the filter used, it may still contain some chemicals or pollutants. If you’re unsure if your filtered water is safe for plants, test it by watering a small area of leaves and wait a week to see if there are any signs of damage.

Filtered and remineralised waterwater, such as from the zazen Alkaline Water System, can remove impurities and toxins and also supply the plants with the essential minerals for abundant root growth and foliage.such as chlorine and lead, harming plants. Filtered water can also improve the taste of plants, making them more enjoyable to eat. In addition, filtered water can help to keep plants hydrated and healthy.

Purified water

Interested in learning how to purify tap water for plants? Purified water has been passed through a reverse osmosis filter to remove impurities. There is some debate as to Given the close similarities, a common question is whether reverse osmosis or distilled water is best for plants. Neither of these forms of filtered water will contain the necessary ingredients for abundant root growth and foliage growth required for a healthy plant.  The missing ingredient ? Minerals.  They are essential for life on earth, the plants need them, we need them, animals need them.  To ensure a healthy plant grown in pots, they need filtered, mineralised water. This type of water is usually safe for plants, but depending on the type of filter used, it may still contain some chemicals or pollutants. 

Distilled Water

If you are considering reverse osmosis vs distilled water for plants, the answer lies in the preparation. Distilled water has been boiled to remove all impurities, but this will also remove the i ncludes minerals., too. True, this makes it very ‘pure’ but also very ‘soft.’. Soft water can be harmful to plants because it lacks the minerals they need to grow. If you use distilled water for your plants, be sure to add a small amount of mineral dust or fertiliser to help them get the nutrients they need.

Alkaline water

Alkaline water has a higher pH than other types of water. This can be beneficial for some plants, but it can also be less useful harmful to others, so it is essential to understand the makeup of your plant first. Fortunately, alkaline water can introduce a range of essential nutrients to improve the cellular hydration and structure within the plant, as well as resist pests and diseases. 

Common FAQs about Alkaline Water and Plants

What type of plants benefit most from alkaline water?

A wide variety of plants benefit from alkaline water, as the added nutrients can help increase the plant's overall health and vigour. Some of the specific plants that benefit most from alkaline water include perennials (Lavender, Goldenrod, Salvias, Foxglove), trees (European Ash, Horse Chestnut, Gingko Biloba, Ornamental Cherry), vines (Boston Ivy, Winter Jasmine, Virginia Creeper), and shrubs (Lilac Bushes, Viburnum, Yew Bushes, False Cypress).  Many of these plants are northern hemisphere natives and it is best to speak with your local gardening centre or nursery where you purchase your plants, they will have a good understanding of the pH of the soil each plant requires. 

Are there any disadvantages to using alkaline water for plants?

Water that is too alkaline can damage the plant's roots and make it difficult for plants to absorb nutrients from the soil. Additionally, alkaline water can affect the soil, changing plant nutrient availability.  It is well documented that the difference in pH can affect the colour of the flowers ! Hydrangeas will put out blue flowers instead of pink if the pH of the soil is too high. 

How often should you water plants with alkaline water?

Assuming you are talking about houseplants, the answer is "It depends." For example, plants native to arid regions need less water than those from tropical rainforests. In general, most houseplants need to be watered about once a week. When you water your plants, give them enough water so that it drains out of the bottom of the pot.

How long does alkaline water last in the soil?

Alkaline water can persist in the soil for long periods, depending on the soil type, climate, and other factors. Alkaline water will likely last longer in arid or semi-arid climates and soils with high clay content.

Can alkaline water be used on all types of plants?

Yes, alkaline water can be used on all types of plants. There are no known adverse effects of using alkaline water on plants. In fact, many gardeners and farmers use alkaline water to water their plants.