Will Washing Machine Water Kill Plants?

There has been a growing concern about using washing machine water, also known as greywater, to water plants. The question is, will it harm or even kill plants? The answer is nuanced.

The Benefits of Using Greywater on Plants

First, let's talk about why using greywater can be beneficial for plants. Greywater is a source of water that has been used for washing clothes, dishes or in the shower. It contains some organic matter and soap residue, which can actually be beneficial for some plants. Soap can act as a natural insecticide and can deter pests from feeding on your plants. Greywater also contains some nutrients that can help plants grow.

The Risks of Using Greywater on Plants

However, there are some risks associated with using washing machine water on plants. The soap residue in the water can build up in the soil, which can change the soil's pH level and make it difficult for plants to absorb nutrients. Additionally, greywater may contain pathogens, such as bacteria and viruses, that can be harmful to plants. The amount of risk depends on what kind of soaps and detergents you use, how much of it you are using to water your plants, and what kind of plants you are growing.

Tips for Using Greywater on Plants

If you plan to use washing machine water to water your plants, here are some tips to keep in mind:

Use mild or natural detergents that contain no bleach, boron or bleach alternatives.

Avoid using greywater on edible plants, such as vegetables and fruits. It is best to use it on plants that do not produce edible fruits or vegetables.

Do not use greywater on plants that are sensitive to salt, as it may build up in the soil over time and harm the plant. Avoid using greywater on plants that require acidic soil, like camellias or rhododendrons.

Use the greywater immediately, instead of letting it sit for a long time. This will help prevent the growth of harmful bacteria and pathogens.

Conclusion

So, will washing machine water kill plants? It depends on a variety of factors, such as the type of soap you use, the amount of greywater you use, and the type of plants you are growing. While greywater can provide some benefits to your plants, it is important to be mindful of the potential risks.

If you are unsure whether washing machine water is safe for your plants, it is always best to err on the side of caution and avoid using it. You can also consult with a gardening expert or your local nursery to get more advice on using greywater for your plants.