How much is too much fertiliser?

[Homer911]

I know this has been touched on a couple of times but I was just wondering what quantities everyone uses on their trees?

Soil conditioners and and fertiliser application quantities are not stated on the label for bonsai.

Yes they are a tree, but normal trees are enormous compared to a bonsai tree.

For example here is a photo of the label of a bottle of Charlie Carp.

cc ferttiliser.jpg

The bonsai category is closest to the indoor plants and ferns (30ml) where as the tree category is (90ml).

Personally I just pour the fertiliser into the watering can without measuring but today I measured..... I add about 150ml of each to my trees every 10-14 days. (Charlie Carp, Seasol, Powerfeed)

I have not seen any illness to my trees due to this.

What is the majority of people fertilising to?

[Truth]

I think fertilising very much depends on your soil/substrate, and frequency of watering. Walter Pall writes of this in his blog.

In essence, if you have a very free draining mix made of primarily diatomite, other fired clays, and inert substances you can afford to fertilise stronger with a high frequency. You trees will need frequent waterings too, which also leeches excess fertiliser. On the other hand, if you have a heavier mix that doesn't drain as easily, it would be wise to not over fertilise so as not to cause salt toxicity build-up.

[alpineart]

Hi Homer911 , mate I measure all liquids to the "tree" recommendation and don't liquid feed often enough, carrying 600-700 litres of powerfeed around here is hard yakka . With liquids , water today gone tomorrow , not quite that quick but flushed out within a few watering .

As for slow release I basically sprinkle it on top of the soil and water in . Volumes depend on pot size , species , grow bed material , etc, etc , too much burns the tree's , to little does bugger all . I only use Rustica Plus slow release and everything here cops a wack of that 3 times a year , grow beds and pots .

Cheers Alpineart

[Josh]

I agree with Alpine. Full recommended strength. All my trees are feed the same rates, natives, exotics, everything. Only time I water it down is if it's a new banksia and I don't know the previous fertiliser program.
You compared our bonsai to indoor plants rather than trees. How often do you repot and root prune your indoor plants. How often do defoliate them, wire them, prune them etc. our bonsai are small but still require good healthy growing to handle what we do to them. A tree in wild can obsorb a lot food through the ground where as our have to get it from a small shallow pot. We also flush out a lot fert with watering so need to constantly replace it. I would say most trees are under fed.

Josh.

[shibui]

I agree with Josh. Indoor plants are watered sparsely to stop the water spilling on the floor. We water bonsai so that water runs out the bottom of the pot every day so that's completely different.
Ferns tend to be soft and sensitive. Most of our bonsai are hardy trees and can take more sun, wind and fert.
Bonsai are trees. They are small so the amount you put on will be smaller. You might water 20 litres of (prepared) fert around a large garden tree but only need 1-200ml to saturate your bonsai. Don't get strength (concentration) of the fert confused with total amount.
Note that the frequency for trees is monthly. Trees in the ground don't get the nutrients leached out of the soil with daily watering but bonsai do. Fertilise more frequently to counteract the leaching by frequent watering.
For my bonsai I use the strength recommended for trees on all fert but try to remember to use it every 2-3 weeks. Also use a slow release like Alpine because I don't always remember I recently heard Grant Bowie saying he fertilises on Mondays. That would make it a bit easier to remember.

[Rory]

I recently heard Grant Bowie saying he fertilises on Mondays.

That must be one heck of a Monday movement. Perhaps he needs to eat more fibre. Could be an age thing.

[Mojo Moyogi]

If:
The tree has plenty of roots, is actively growing, ie. not dormant and if it is in good health.

Then:
Full strength. Preferably Organic. Fortnightly. Saturate.

Cheers,
Mojo