I use my leftover tea to water my plants - here’s why you should too

I have a confession to make. I have been using my leftover tea to water my plants for years, but I had no idea if it was good or bad for them. However, gardening experts have now revealed that watering plants with tea is the hack you need to follow for your house plants ideas.

My current house plants include a banana leaf plant, pinstripe Calathea and admittedly one which is a rogue IKEA plant I don't know the name of. Even the house plants that are impossible to kill sometimes don’t make it and the water you use could be the culprit. 

If you want to look after the best house plants well Gene Fitzgerald, home water treatment expert at BOS warns that although the UK has some of the best tap water in the world, it’s not always the best for our plants. 

Watering plants with tea

‘Hard water contains high levels of calcium and/or magnesium and plants can be overburdened by calcium and magnesium deposits and prevented from imbibing other nutrients.’

That doesn’t mean that soft water is the answer either, Fitzgerald adds, ‘If you have a water softener installed in your home it will deal with water hardness, but carries its problems. Including the introduction of excess sodium. Which is terrible for most plants.’

Plus UK tap water is treated with disinfectant so it is safe to drink, but this can often contain chlorine which kills the helpful bacteria and soil microorganisms plants need to stay healthy. 

While there is the option to boil water and leave it to cool to help remove some of the limescale deposits, the cost to run a kettle can make this an expensive option. But that is where my leftover tea comes into its own.

Not only is my tea watering hack making use of pre-boiled water, but it also contains some other handy ingredients to help plants thrive. Angela Slater, gardening expert at Hayes Garden World, says ordinary breakfast tea works perfectly for plants that prefer slightly acidic soil because the tea lowers the PH. 

‘Teas also contain minerals such as iron, calcium, zinc, magnesium and nickel as well as Vitamins C, D and K. They also contain traces of nitrogen, phosphorus and potassium which are essential for the growth of healthy plants. 

‘The nitrogen content can be higher than a lot of specific plant fertilisers so for plants which need more nitrogen, teas are a sure-fire winner.’ However, she adds that organic teas are better than non-organic teas which can still have traces of pesticides.

I always make sure I let my tea go cold before watering my plants because hot tea can shock the plant and affect its growth. Angela Slater from Hayes Garden World also recommends not watering your plant with tea every time and ideally using rainwater or filtered water in between.

Now that I know for sure my leftover tea hack has secretly been helping my plants, I don’t plan on stopping anytime soon.

But, will you be joining me?