Fertilize Your Peace Lilies With Common Household Items

Peace lilies (Spathiphyllum spp.) are adored by gardeners worldwide for their elegant, white blooms and rich, dark green foliage. These plants are not particularly picky about their growing conditions, especially when it comes to light and fertilizer. They thrive in low-light environments and get by just fine without being fed often. Just fertilize them in the spring and summer, and your peace lilies will flourish. That said, if you want to perk up your peace lilies and encourage them to bloom during their growing season, giving them a boost of nutrients is a great idea. Since peace lilies do not tolerate chemicals well, you'll need to stick to using organic fertilizers. Fortunately, some common household items may serve just fine in this capacity. 

Spent coffee grounds, Epsom salt, and even banana peels — items most of us have on hand at home — can give peace lilies a much-needed injection of nutrients. All of them offer a unique combination of minerals and elements that will enrich the plants' potting medium. That said, you must take great care when using these items as plant food, since incorrect or unnecessary applications can be not only futile, but they may also harm the plants. 

Spent coffee grounds, often seen as a useless byproduct of your morning brew, are a hidden gem in your gardening toolkit when you're caring for peace lilies. They're not just a waste product; they're rich in nutrients, especially nitrogen, which peace lilies need for healthy leaf growth. The most effective way to utilize the nutrients in the grounds is to add them to compost, then use the latter to top dress the soil in which you grow the peace lily. The ideal coffee ground content in the compost is about 20%; any more than that, and you risk harming the plants. 

You may be tempted to mix coffee grounds into the soil directly, but they won't release the nutrients in sufficient quantities. What's worse, microorganisms in the soil will get to work breaking down the matter and will starve the soil of nitrogen in the process. That said, adding coffee grounds to the growing medium can protect your peace lily from numerous pests and improve soil structure and drainage. Just make sure that you don't add to much — any caffeine content remaining in them could prove toxic to the plants. 

Another household item you can repurpose as a peace lily fertilizer is Epsom salt, chemically known as magnesium sulfate. Magnesium is a key component in chlorophyll production and is essential for photosynthesis and overall plant health. When peace lilies lack magnesium, their leaves often turn yellow. In the short term, Epsom salt could cure the plant's magnesium deficiency.  

That said, adding more magnesium to the soil than it needs is not only unnecessary — it's outright detrimental to your plants. The key issue here is that excess magnesium in the soil keeps plants from absorbing calcium properly, and calcium deficiency may manifest in smaller foliage and necrotic margins on leaves. To avoid exposing your peace lily to a nutrient it doesn't need, test the soil before you treat it with Epsom salt. If you're sure that your peace lilies' potting medium needs a magnesium boost, dissolve 2 tablespoons of Epsom salt in a gallon of water and use the mixture to water the plants. After the initial application, test the soil for magnesium content to determine if more Epsom salt is needed. 

Peace lilies prefer natural fertilizer, and there are plenty of online sources claiming that banana peels work like magic to make these flowers bloom. And there's some truth behind that claim, but you shouldn't bury banana peels directly in the peace lilies' potting medium. The peels are indeed loaded with helpful nutrients like potassium, which helps bloom production. But as the peels decompose in the soil, the microorganisms breaking them down will consume copious amounts of nitrogen, leaving a nitrogen-poor medium for the plant. Likewise, there's no point in trying to make fertilizer by soaking banana peels in water; the nutrient concentrations in the liquid will simply not be sufficient to meet peace lilies' needs. 

Instead of wasting time on these disproven "hacks," take advantage of banana peels' rich nutrient content by adding them to your compost pile. As a compost ingredient, banana peels actually add high quantities of nitrogen, phosphorus, and potassium — often as much as two to three times more than you'd get without them. You can then use this banana-enriched compost to top-dress the peace lilies' potting medium to give them a balanced, nutritious fertilizer.