Fertilising peace lilies can cause people a lot of unnecessary anxiety, so I’m gonna preface this article by saying that there is absolutely no reason to overthink this.
Pick a fertiliser, pick a schedule, and stick to it.
Fertiliser is supplemental care. I wouldn’t advise skipping it all together (though you absolutely can) BUT it’s something to learn after you’ve mastered watering and light.
Why do we fertilise peace lilies?
Fertilising your plants has the same effect as overhauling your diet. It can make a massive difference BUT it’s not the only thing you need to consider AND there’s only so far it can take you.
A perfect diet is awesome, but you also need sleep and relationships.
A perfect fertiliser regime can be beneficial for your plant, but only if everything else is taken care of. Fertilising a plant that’s overwatered and kept in a dark room is largely pointless. All the different factors that influence plant growth need to be balanced.
However, if your peace lily is healthy and growing, adding fertiliser can result in larger leaves that are glossy and well-conditioned. Growth is faster, you’ll get bushier growth and you’re more likely to get a lot of flowers.
When to fertilise peace lilies
I talk about this a lot, but I think it’s important, especially for people like me who struggle with perfection paralysis and won’t do anything unless they know what they’re doing is 100% correct.
There is no correct when it comes to houseplants. They’re not like tomatoes and lettuce which have been studied by scientists for decades to best understand how to help them thrive.
It actually benefits the houseplant industry if we’re not great at caring for them because we’ll buy more.
So no one knows what the perfect peace lily fertiliser is. No one knows exactly how often they should be fed. If you google ‘are peace lilies’ heavy feeders?’ you might get 30 articles that all claim different things.
All we can go on is anecdotal evidence.
So try stuff out. If your peace lily likes it, keep doing it. If it doesn’t stop.
How often?
I feed my peace lily every other time I water it – ish. Sometimes it’s every time I water, sometimes it’s every third time.
I didn’t come up with this schedule for the benefit of my plants. I do it because sticking to adding nutrient water every other time I water is an easy schedule for me to remember.
Every six weeks is often enough to fertilise houseplants BUT that’s too infrequent for me. I end up building it up into a bigger deal than it is, then think that I don’t have time to do it and it gets pushed to an annual thing.
When it comes to fertilising frequency when growing your peace lily in LECA or water, then it’s a little different. I, as a lazy person, simply top up the reservoir when I’m watering my other plants. Flushing is an annual thing (if they’re lucky).
Ideally, you should be adding nutrient water monthly. Top up with plain water as required for the rest of the month, and then dump out the old water and replace it with new nutrient water.
What about fertilising in winter?
I’m not currently running any grow lights or heat mats or anything, so my plants are well aware that it’s winter. I don’t fertilise in winter. I don’t think it’ll do them too much harm but it’s unnecessary and I’m lazy.
If you don’t notice your plants slowing down for winter, then keep on feeding them as normal.
Which fertiliser is best for peace lilies?
Again, there is not enough research into the fertiliser requirements of peace lilies to offer any useful advice. I use the General Hydroponics Flora Series and it works really well. When it runs out I’m going to switch to a one-step fertiliser like Dynagrow though. Again, out of pure laziness.
There are various options when it comes to peace lily fertilisers:
Standard houseplant fertilisers
Go for this. Just find one on Amazon that has good reviews. One of the great things about the houseplant hobby is that it attracts people of a certain age who LOVE to give really detailed Amazon reviews complete with pictures.
Asking in Facebook groups is great, but there might be 30 replies, all recommending a different product.
The one thing I will say is that if you’re planning on keeping your peace lily in water or LECA, go for a hydroponic fertiliser. They can be used on all substrates, and that way you don’t have multiple bottles of fertiliser.
Worm castings
A great lazy choice. Worm castings are worm poop and it’s extremely nutritious for plants. Add a thin layer to the top of your soil at the start of spring.
I mix my worm castings into the soil when I repot, because the bushy nature of the peace lily growth pattern makes adding a thin layer to the surface of the soil easier said than done.
DIY fertilisers
Avoid.
Anything that you can make from food scraps is out. No:
- coffee grounds
- banana peels
- vinegar
- compost
- manure
I’m not saying they don’t work. They do. But they will attract so many fungus gnats and they’ll drive you round the bend. Don’t do it. You’ve been warned.
If you can’t afford fertiliser for your peace lily, skip it. Ask for some for your birthday or Christmas. A year without fertiliser won’t harm it. You throwing it into the sea because you’re sick of fishing gnats out of your wine glass will.
Also, avoid things like Epsom salts and cinnamon. They’re unlikely to have any impact on…anything.
Tomato feed
Tomato feed is a perfectly fine option for peace lilies but its purpose is to promote healthy fruits. Peace lilies can produce berries but you’d need to pollinate the flowers and there’s not really much point (they’re inedible).
The jury’s out on whether it helps promote flowering. In my experience flowering is determined by light and watering as much as it is feeding.
If tomato feed is all you have it’s better than nothing. I’d dilute it more though – so use half the amount of fertiliser that the manufacturer recommends but the same volume of water.
Slow release pellets
Slow-release pellets are a great option for people who know they won’t water in fertiliser. I don’t like them because there’s no real way of telling when they’re used up, but I’m pretty sure that adding more whenever you repot is all you need to do.
Fertiliser spikes
I don’t like fertiliser spikes. They don’t distribute the feed well at all, so you end up with a combination of root burn and roots with no access to nutrients at all. They can be a good option in large peace lily specimens because you can add multiple fertiliser spikes around the plant to ensure an even distribution.
I just don’t like how you can’t tell where the nutrients are. Am I overthinking this? If anyone has success with these, please let me know!
What happens if you don’t fertilise peace lilies?
Nothing. As someone who has gone literal years without feeding her peace lilies, good care can keep them thriving without needing fertiliser.
Fertiliser improves the condition of your plants, but they likely get the vast majority of the nutrients that they need from their substrate. If your plants are growing, they’ll need repotting every year or so.
When you repot, you add in fresh potting mix with fresh nutrients.
This is enough to keep your peace lily happy. Would feeding it improve it? 100%. And if you treat two plants identically but you fed one and not the other then the one you fed would almost certainly be bigger and look lusher.
But if you don’t fertilise your peace lily, it won’t perish.
HOWEVER
This is all assuming we’re keeping our peace lily in soil. Soil holds nutrients. You can add things like worm castings to boost nutrients.
If you keep your peace lily in LECA or water then you will need to add nutrients. There are people who have decades-old peace lilies kept in water that never feed them and they’re perfectly healthy, but that’s a fluke. Or they have extremely mineral-rich water.
I hope you found this helpful. I know it’s annoying that there aren’t more clear-cut rules for feeding houseplants, but there’s a massive gap in the research.
If you have any questions, feel free to leave me a question below.
Before you go, you might find these articles useful:
