You Don’t Need To Use The Aerogarden Fertiliser (But You Can’t Just Use Anything)

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One of the reasons I’m such a huge Aerogarden convert is that it tells you when to add fertiliser. Honestly, more plants should be doing this.

TECHNICALLY I could set up a reminder to flash red every six weeks so I remember to fertilise all the other plants, but…no, I should do that.

The fertiliser is meant to last the lifetime of your plants, but after using the initial pods, many of us go on to put non-Aerogarden seeds (or cuttings) in the Aerogarden. Then what?

I mean, ideally we’d hop over to Amazon and get the same stuff again. It has awesome reviews and has been expertly crafted by the Aerogarden guys to be extremely efficient.

But what about those of us that can’t get hold of it (i.e. everyone in the world apart from those that live in America?). I love the Aerogarden – why do they not love me?

The good news is that there are tonnes of alternatives you can use, but the bad news is that you can’t use any old fertilizer you have lying around.

What is the standard Aerogarden fertiliser?

They don’t say, beyond some very vague mentions of pH buffers and mineral salts. The N-P-K is 4-3-6.

I mean, it’s a patented formula, so there’s SOMETHING in there that’s unique enough to warrant a patent, but they ain’t saying.

Why do people want alternatives to the Aerogarden fertiliser?

One of the main reasons I’ve seen for people wanting to move away from Aerogarden’s own liquid food is that they don’t like the company that owns it, Miracle-gro.

There seem to be a few reasons that people are so anti-Miracle-gro, but so far I couldn’t find anything that definitely convinced me to avoid them. There were people claiming that mineral fertilisers are horrific for the environment, people that are mad that Miracle-gro isn’t organic, and people that say miracle-gro attracts fungus gnats in droves.

The fertilisers being bad for the environment seemed a bit, er, naive.

Whilst fertilisers are harmful to the environment, the issue comes from vast quantities being dumped in waterways. This is a problem caused by those using fertilisers on a commercial scale – organic or no.

It’s also ALL fertilisers, whether it’s chemical or manure straight from the cow. If large amounts make their way into rivers, then the plants all grow crazy, throwing the balance off, oxygen depletes, and everything dies. That’s a rather dramatic account, but it’s broadly what happens.

Alternatives to the Aerogarden fertiliser

I use the General hydroponics Flora series, because that’s what I have. Just be aware that if you’re mixing your own nutrients, then you’ll need to check the pH and adjust it*.

*So when I was starting out with semi-hydro and leca, I used to do this, but after about three sessions of having perfect pH right off the bat I stopped doing it. This isn’t advice (wink wink) just…what happened.

Can you use any fertiliser in the Aerogarden?


Potting mix has various nutrients in it that plants can absorb, so some soil fertilisers aren’t, er…complete? Full spectrum?? You know what I mean.

Not only that, but the quantities of certain ingredients have to be different because water can ‘lock up’ nutrients and prevent the plant from absorbing them. That’s why when you mix up the FLora series, you have to add the purple one first (I think?) and then the others after, and it’s also why you can’t mix the three together and then add it to water – each has to be added to the water separately.*

*I’m finding this hard to explain. The process is to get your jug of water, and then add Flora Micro and stir. Then add the next one (it doesn’t matter which). Stir. Repeat. Done.

You can use any hydroponic fertiliser to the Aerogarden, but it must be hydroponic.

Here’s an article that goes through the various models and the capacity of their water reservoirs.

I’m lazy, so I’d probably just make up a 5 litre bottle of nutrient water and add it every time it asked for water.

How often to fertilise the Aerogarden

If you’re using the normal Aerogarden fertiliser, then add when the green leaf button flashes red. I can only assume it knows what its doing, and I’m not an experienced enough gardener to argue.

But if you’re using your own fertiliser, then you may need to adjust the amounts. As I said before, I’d be tempted to make up a nutrient solution and just add that every time I’m prompted to water.

If you notice any fertiliser burn then maybe hold off, but if you’re only adding 1ml of Flora Micro (I can’t remember the amounts of the other two, but it says on the bottle – I always use 1ml of Micro).

How to switch over nutrients in the Aerogarden

Lockout (where the plant can’t absorb the nutrients in the water) can occur when you mix incompatible fertilisers, so it’s best to clean the Aerogarden thoroughly when you switch over.

If you’re in the middle of growing something, take out the pods and sit them in a jug of room temperature water.

Then clean your Aerogarden – I have an article on how to this here. Then set up the systems again and put your plants back in.

Ideally you’d wait until you were starting new seed pods before switching fertilisers, but for those of us that can no longer get hold of the products, we may not have a choice (she said, bitterly).

Final thoughts

You can use any fertiliser you like in the Aerogarden, but make sure that it’s formulated for growing plants hydroponically. You may also have to play around to find the optimal dosage – though the Aerogarden plant food is a standard dosage many people like to play around with different fertilisers to better suit what they’re growing. Lettuce, for example, is happy with the Aerogarden nutrients, but many people that grow fruits like tomatoes and hot peppers prefer to switch over to General Hydroponics to get tastier fruit.

Caroline Cocker

Caroline is the founder and writer (and plant keeper) of Planet Houseplant

4 thoughts on “You Don’t Need To Use The Aerogarden Fertiliser (But You Can’t Just Use Anything)”

  1. I just came to get some info on what to replace Aerogarden ferts with, but for everyone out there wondering why miracle-gro is actually bad, I’ll explain.

    Salt-based nutrients are not only environmentally hazardous because of runoff from use, but also from production. Regardless of how much you’re using, the runoff from production will cause pollution.

    Secondly, Miracle-Gro is the exclusive distributor of Roundup. If you don’t understand how Monsanto is terrible for the environment, look into monoculture farming, and how it caused the dust bowl.

    Thirdly, to attack organic farming as a whole is quite a bad faith argument. You can absolutely source salt-based minerals from organic sources for farming; however, farmers who really care about organic food don’t use these fertilizers. I successfully pull crops out of my raised beds every year using just compost and compost tea. Every once in a while I add some fish poop for microbes and nitrogen. No salts.

  2. Thanks so much for explaining. The UK was all set to ban glyphosates but now it’s approved for use until 2025, though a lot of local councils have banned it. Monsanto also invented DDT! Well done guys!

    I grew a tremendous volume of tomatoes in raised beds using homemade compost, watering with aquarium water and occasionally emptying the contents of the aquarium filter on there.

  3. I certainly agree that it would be nice to get away from the miracle gro. It was once part of Monsanto (now Bayer.) I’m not sure that’s made any difference, but I certainly would use an alternative.

    I think that for this article, they are correctly asserting that organic vs nonorganic fertilizer makes little difference to the environment when it comes to an aerogarden. It’s more nuanced than this article gets into, but the gist is there.

    I think the bigger impact is having a reliable source of vegetables that can be grown in an apartment or urban area. The sourcing for the electronics and plastics are a big hurdle to get over the carbon foot print. Still, if you look at the amount of energy it takes to transport the produce, transport the labor and the amount of waste in that process, you’d get close if not surpass the carbon efficiency of big agriculture. Of course if you have the ability to use renewable energy sources like solar or wind to power the garden, it’d be a big step towards overcoming mass production efficiency.

  4. They’re growing tomatoes hydroponically in disused parts of the London underground, which is really cool. Combating food waste is also really important – it’s estimated we throw away a third of the food produced for humans, which is both ridiculous and sad.

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