Citric acid in plant pots.

[John Brown]

I stupidly left a bucket of citric acid that I'd used to de-rust an old combination plane sitting outside.
My wife, assuming it was rainwater, used it to water our Christmas tree(that we take in for Christmas, and has survived for 5 or 6 years) and another plant.

Does anyone know whether the tree is likely to survive, or am I going to be spending Christmas in the shed?

I think I had added around 1/2 cup of acid powder to around 1 gallon of water, but that was well over a week ago, and it has rained loads since.

John

 

[hanser]

Be prepared to take your punishment like a man

Seriously, no idea I'm afraid

 

[DrPhill]

I am not certain, but I would not give up hope. Conifers usual thrive in acid soil - though probably not that acid. Citric acid is an 'organic' acid (in that it is composed of carbon, oxygen, and hydrogen, and also in the sense that it is produced in natural living systems) so if the sudden drop in pH does not kill the conifer it is unlikely to be poisoned by anything in the acid.

The only action that I can think of is watering the pot with copious amounts of tap or rain water. If you are in a hard water area, then I would use tap water, as disssoved chalk will help nutralise the acid). Even in a soft water area I would water copiouslu, because conifers are good at moving the water away from their trunks to the 'drip-line' where they have more surface rootlets to absorb it. Unfortunately, in a pot, this has the effect of causiing the water to miss the pot - so our generous rain supply might not have done as much good as you may have hoped.

If the citric acid does kill the tree, then accept our sympathies, but please tell us as I have some candidates for a similar mistake.....

 

[andersonec]

Depending on what your compost consists of (is it fairly free draining?) you can 'flush' it though, take it outside and leave a hose pipe running gently so that the water trickles through, a few hours should see it clean enough.

Conifers have a symbiotic relationship with certain mycorrhiza (fungus) and one can't live without the other, on a healthy pot grown conifer you will see a grey fungus throughout the compost, some folks think this is a disease. The danger of the citric acid in your compost is the killing of this fungus hence the need to flush it out.

There are various other reasons why it should be removed but that one will do for now.

Andy

 

[John Brown]

I will get the hose trickling into the pot. Re. the rainwater dilution, I was talking about the bucket, not the tree.

John

 

[andersonec]

John, the dilution of half a cup to a gallon isn't much but it all depends on the size of the container your tree is in, obviously a 3Ltr pot is going to have a much stronger solution than a 30ltr pot but flushing it through will help remove the majority, this treatment can also be used when pots are over fed with fertilisers.

Depending on how long your tree has been in the pot, you mentioned 5 or 6 years, and if that is the case then it needs repotting and that can be done anytime between November to April, remove about a third of the compost from the outside of the rootball and cut the long trailing roots which have beed exposed, repot with fresh compost into a pot slightly larger than the previous and sit the tree in a position out of the wind, start feeding your tree in May/June through to Sept,

Containerised plants are best fed with organic fertiliser as this will not have any adverse effects on the compost and it is difficult to overfeed with organic, a good source of organic fertiliser is a water butt (if you have one) and a couple of shovel fulls of cow muck in an old pillowcase, this is strung in the waterbutt like a teabag (make sure you have a lid) and shaken up everytime you you use some of your water (a dilution of half a litre to five litres is good) cheap and highly efficient. It is easy to disrupt the organisms in the compost if you use chemical fertilisers, if you have to use chemical fertilisers then use it half the strength of what it says on the pack and use a 1:1:1 fertiliser (it will have it on the pack).

Feeding containerised plants is important because nature doesn't do it for you the same way it does in the wild, and if you don't feed it then 'survive' is the right word, it should 'thrive'

Regards.
Andy

 

[John Brown]

Thanks, we have already repotted it once a year or so ago.
I believe it is container grown, rather than containerized(I wouldn't have known the difference this morning, but I was listening to GQT on Radio 4 whilst in the car this afternoon, and they had a Christmas tree expert on).
To be honest, I think it will be too big to drag into the house in a couple of years, at which point we will need a smaller tree or a bigger house.

John