Hello, i'm new here and ready to ask my first question

I went to a gardening supply store to look for stuff i need to take care of my 3 new citrus trees (key lime, meyer lemon, calamondin) which are all growing in containers, about 1.5-2 ft tall. They are all currently flowering and the meyer and calamondin have a few small green fruits They all look healthy, except for a few yellowing leaves at their bases, which i suppose is normal (shedding old leaves?).

I didn't find fertilizers in the recommended 5-1-3 ratio so i'll keep looking for that, but i did find liquid seaweed extract to provide micro-nutrients.

My question is about orchid mix. I read on this forum that CHC+sphagnum moss is a good container medium for citrus, but that the CHC needs to be processed to leech out excess sodium first (cation exchange). Do i need to do that for CHC orchid mix (which is the only CHC i could find), or is it already ion-balanced? I'm not sure orchids like lots of sodium...

I'm not ready to re-pot my citrus yet, i see no roots coming out of the drainage holes so they still have some space. I want to delay re-potting to avoid traumatizing them even more after taking them out of their cozy nursery greenhouse.

I haven't been this excited about growing things since i was a kid helping my mother in her garden, and being in Montreal (Canada) citrus will be quite challenging!

Thanks for any reply!

Welcome to the forum. I don't know much about CHC Orchid mix, so I will let others answer that, but the bark based orchid mix works as well.

Good luck with your citrus trees--there are several others on the forum from Canada, so it can be done.

I looked into it further and the mix i saw is a mix of bark and CHC. Here's a link:

http://www.fafard.ca/index.php?module=axialboutique&func=view_one_product&id=122&cat=3

It also contains limestone (powder i assume), it might make the mix too basic. I'd have to soak it in a weak vinegar solution to remove it and then rinse out the excess vinegar...

The limestone powder could be needed to balance the low pH of some organic materials and also de toxify phenols in pine bark. Also the mix pH is used to control the plant availability of micronutrients, which become toxic in excess. For example naturally high levels of manganese in pine bark are not able to be taken up by plants, if the pH of pot mix is adjusted to around pH5 to pH6.5 Other elements behave in the same way.
I would contact them to find out what pH they aimed for when they mixed it, before trying to leach excessively. If their pH is more than 6.3 to 6.5 it is getting high for most plants in pot mix.(maybe Orchids are different?)
Also if you cation exchange with Ca nitrate, you will be adding extra to the Ca carbonate(lime) which may increase pH. Possibly if you fill the pot and pre water a few times before you plant your tree, it will be sufficient ?
Many members of the forum are buying bales of peat, bark, coir etc and mixing from scratch, wheras you are starting with a pre designed pot mix and several things have already been done.

Normally, high levels of manganese is not found in pine. High levels of manganese is found in hard woods. Although, the perfect pH for citrus is 6.5, citrus does well at higher pH levels such as 7, and still does OK at a pH of 8. For the above mix I would think the critical item would be how well the drainage is, especially over time. - millet (957-)

Thank you for all your replies

The mix is pretty coarse, with most chunks ranging from half an inch to a quarter of an inch. The bark chunks have a more elongated and flat shape, this will problably prevent the mix from compacting too tightly overtime. So it will probably drain quite well. I'll add some sphagnum moss, this will help acidify the mix a bit.

What i could do is soak some of it overnight and test the water with pH strips. I'll use tap-water since this is what ill be watering with. I'll also repeat the experiment with the fertilizer when i figure out how to acheive the 5-1-3 ratio with what i can find in store. I've had the trees for almost 3 weeks now so they are due for fertilizing.

Philippe