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Vague fertiliser instructions

I have a bottle of liquid fertiliser.

Its application instructions read:

Apply once every two weeks from Spring to Autumn:
- Using a mixture of two screwtops for each five litres water
- Cloudy days or in the evenings you may spray using one scretop for each five litres water

Now in my books, I read that before applying fertiliser, you should water your tree before hand. I'm naturally assuming that:

Two screwtops to five litres water is water soluble, and meant to be diluted.


Does it mean if I water with 2.5 litres water, I should pour a single screwtop of fertiliser onto the soil after?

All logic points to diluting it (the spray instructions should give it away), but I do just wish to make sure.

Back to the 'watering well before hand'; should I be aiming to water well, trying to judge prior to water coming out of the drainage holes, and then applying fertiliser?

Finally, 5 litres?! That's a ridiculous amount of water for a pot that in dimensions is approximately 18.2cm x 11.43cm x 5.08 - that only holds 1 litre of water when empty!

I used half a litre of water, and added 20% cap full of fertiliser to keep it proportioned, and poured in a third every 5 minutes or so to give it time to absorb, and ceased watering when it began coming out of the drainage holes.

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Joined: Tue Sep 25, 2007 9:07 pm
Location: Minnesota zone 4

Re: Vague fertiliser instructions


I would mix 1 cap of fertilizer to a gal. of water.

Water the entire surface of the soil with plain water first until you get some drainage, wait 10-15 min. then use the fertilizer solution. Water a little at a time over the entire surface of the soil until it drains.

You do not have to use the whole gal. at one time.

Never fertilize dry soil as it could burn the roots..


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Dilute the fertilizer according to the directions before applying to the soil. Do not apply full strength. The instructions are not meant to imply that you need to use the entire 5 liters on a single plant.

Here's the procedure I use. Water thoroughly making sure to wet the entire surface of the soil. Use enough water that it flows freely from the drainage holes. Wait a few minutes for the initial water to be absorbed then water again, again allowing the water to run freely. I do this every time I water. This is not over watering. The key is to then wait until the plant really needs to be watered again. This could be the next day or several, depending.

On days that you intend to fertilize do so on the second round of watering using the diluted mixture. Use only enough so that you are sure the soil is saturated with the mixture. Letting too much run out or using such a large amount as 5 liters is wasteful and does no more good than if you used just enough. The remaining fertilizer can be used on other plants you may have or saved until next time.


I see Phil already answered your question while I was composing my reply but here it is anyway.

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Joined: Fri Mar 07, 2008 12:07 am
Location: Airmont, NY Zone 6/7

Just wanted to add a couple of things. First, bonsai are traditionally fertilized using a half strength mixture of most fertilizer formulas. It's always better to under fertilize rather than over fertilize.

Second, the dilution is to get a concentration of elements in the water. This concentration is then applied with the mixed water. Because some pots are larger and others smaller, the amount of water added to the soil will be variable, but the concentration of fertilizer (i.e. large plant versus small plant) will be proportionate according to how much water is needed. Make sense?

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Joined: Sun Aug 03, 2008 3:41 pm
Location: Surrey, UK

Excellent. I'm immensely grateful.

I used 500mls and 20% of the cap full as this is the same proportion as 5 litres to 2 caps of fertiliser.

I shall be applying fertiliser with the way you suggest, Gnome/Arboricola. It sounds logical, and obviously comes from far vast experience than I hold.

Many thanks for clearing that up for me.

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