Changing the nutrient mix in your Aerogarden easily


The Aerogardens consist of a grow bowl, lighting and timers to assisaerogarden harvestt in the easy growth of your plants.

This gives them all they need without having to resort to adding soil.

Placing seed pods– either pre-seeded or grow your own – into the holes will give you the crop you are after.

The pods act as a support for the small amount of grow medium to hold the seeds while it germinates.

In the grow bowl there is a mix of nutrients and water. The plants consume both of these and when there is little useful nutrient left the best thing to do is to replace it.

Every time the lights start flashing on your Aerogarden you should be changing the nutrient mix in your Aerogarden. As there is only a small opening in most of the Aerogardens it does become tricky to do, so the use of a pump and pipes is advantageous. This way the water and nutrient can be pumped out and then the new nutrient mix can be pumped in easily.

The manuals state that you can just add more nutrient at the time the lights start flashing ,but if you do this then the water becomes more concentrated with unused nutrients that the plants don’t want and this can cause them problems taking up the nutrient.

To prevent this state from happening and to get the best out of your Aerogarden indoor hydroponics unit you are better off replacing the whole of the plant food.

The lights start flashing to replace the nutrient every two weeks…

In the beginning

When you first start to grow your seed kits, then this is the one time you can skip replacing the nutrients, and not add any more…

As the seedlings are so tiny and have only just gone through germination, they will not have consumed all of the useful nutrients out from the solution.

After another two weeks…then is the time to start replacing the mix.

Depending on the kit planted will depend on how much your plants consume the water over a day.

Routine maintenance

It is very good practice to get into the habit of checking your plants daily, and checking the level of the nutrient mix.

A quick top up will prevent the nutrient becoming too concentrated.

If you wait until the add water light comes on then there will be a fairly concentrated level of liquid nutrients in the grow bowl.

Keeping a jug of water close to the Aerogarden so that it becomes room temperature and any chemicals can evaporate off is useful.

I keep a 1 litre jug of water on a shelf under the Aerogardens i have running.

If the light does start to flash for add water then you do need to add more water.

This may happen during hot times of the year as the plant, just like us, will start to ‘sweat’ to keep cool.

Once it starts doing this the level of water will drop fairly rapidly and you can help your plant out by using a fan to have cooling air run over it.

The concentration of nutrient will go up and down as the water is removed and replaced, but the plant will survive, if you keep an eye on it.

Changing the nutrient mix in your Aerogarden

As the two lights start flashing to indicate the at you need to replace the liquid plant food.

The manual says to lift the lid and add more of the Aerogarden plant food.

Doing this will increase the concentrations of the nutrients the plant hasn’t absorbed, or needed, from the last feed.

Doing this over the whole of the grow cycle can lead to plant stress or in extreme cases plant death as the plant cannot take up the required nutrients due to the concentrations of the unwanted nutrients.

The best way to overcome this is to completely replace the nutrient mix in the grow bowl.

This way you will get better growth for a larger harvest and healthy crop.

It might look time consuming and difficult to do from the write up in the manual…taking the whole grow bowl and plants to the sink and lifting the plants out and pouring the leftover nutrient away and…..

But you can achieve the end result easier and with more care for your plants.

If you gather together

siphon pump for replacing the nutrient mix in your aerogarden
Amazon link for siphon pump
    • Two buckets – each able to handle the capacity of the grow bowl.
    • A siphon pump.
    • The liquid plant food that you are using
    • A mixing stick
    • A measuring jug
    • And a syringe….

No you are not going to be injecting the plant food into the plants themselves, it is just for measuring….

Note: please keep the buckets for this only and not for general use, like car washing or mixing pest control as any residue may contaminate the food for your plants. watering the garden is fine…just no additives….

The method

Once you see the lights flash on your Aerogarden then use the measuring jug to get enough cold water to replace all of the nutrient mix for your system.

Leave it to stand, preferably overnight to become room temperature and any chemicals that can evaporate off will.

The next day add the required amount of liquid plant food to the water and give it a swirl around to mix it thoroughly.

If you are using a two part mix – make sure you mix the first part well before adding the second and mix that as well…

The clear is not easy to see if you have mixed it in, but swirl it around then go the other way and it should be ok.

Lift the lid for the filler on the aerogarden.

Insert the siphon pump until the end of the pipe reaches the lowest part.

Insert the open end of the pump into the spare bucket.

And pump the spent nutrient mix out of your Aerogarden.

Please note that if you have one of the older models, that you will need to switch it off when doing this as running the pump dry will cause increased wear.

The newer units that come on for 5 mins every hour, you can time the nutrient change until after the pump witches off…

Once you have all of the mix out of the grow bowl, then move that bucket out of the way.

Bring the bucket with the new mix close to your Aerogarden and turn the siphon pump around.

So the nutrient will be fed from the bucket into the Aerogarden.

Keep an eye on the ‘fill to here’ marker and stop when you reach the top.

And that is it….

Some will say it is time consuming, but i can do three of my units with a hand siphon in about 30 mins…

And that is mixing, emptying and replacing all of them….

And the leftovers

So you now have maybe a little new nutrient leftover along with a bucket of old nutrient.

The new nutrient you can save for the next top up of your unit, or you can give your house plants a treat.

The used nutrient can also go onto your house plants or garden plants as added nutrient for them.

It does store, but remember this is now still water and any oxygen will quickly deplete, so don’t drown your plants you add this to.

Nothing needs to go to waste from the Aerogarden.

Make sure you look at the waste nutrient to see the condition and if there are any roots in there.

It may be paler that the new nutrient as this will be various minerals taken out by the plant…( with this i am assuming you are using a two part mix nutrient).

Just keep an eye on the amount of root debris in the waste as too much of a build up may indicate root rot…

If this occurs then the addition of an air stone and air pump will reduce this, as long as it is recoverable.

Different plants

It may be obvious that different plants have different nutrient needs…

A slow growing rosemary may not use up as much as a fast growing tomato…

So taking this into account will determine if you need to do an intermediate change of nutrient.

As a tomato plant grows you may find that you are topping the water up twice a day in a smaller Aerogarden unit, whereas the farm xl unit will adequately handle a number of standard tomato plants.

If you do see your plants wilting, check the level of the nutrient mix in the grow bowl and top up if basil growing after replacing the nutrient mix in your aerogardennecessary…

Or replace it….

Let me know if you have an easier method of changing the nutrient mix in an aerogarden as i am sure this is one of the things putting people off taking up this wonderful method of growing herbs, flowers, and other crops.


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I have been growing plants hydroponically since 2009. For years before that i was reading books and looking at systems and saying way...
But once i had taken the plunge with the tomatoes outside, then there was no stopping me.
I tried out most of the systems and started to refine them, getting the plants to grow more efficiently.
Now I am more interested in indoor hydroponics and the challenges it presents. Being able to control the environment, feeding the correct nutrients and giving the correct length and type of lighting....

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