Hi Lydia & welcome!
To break down --use one tsp. calcium nitrate to one gal. water in final soaking of chc's.
Calcium nitrate =calcium & nitrogen
Dolomite = calcium & magnesium (or epsom salts).
What I did last yr to prepare chc is --soak (just couple hrs) rinse, soak, rinse, rinse, rinse till water is clear. Then last soaking (1-2 days), I added epson salt & some pelletized lime (same as dolomite), & soluble 24-8-16 fert. ... all about 1 Tbls per gal water. This was all I had.
My problem was I used 1/2 chc to 1/2 my old soil. It stayed to wet as the proportion was wrong -almost lost them to root rot. I recently repotted using more chc -4to 1 ratio. Hope this helps.
Patty

Hi All

I have been using CHC`s for about 10 months. I did not know about cation.
I washed them real good in plain water and all of my citrus trees are doing just fine?? Am I just lucky? Or maybe the peat and top soil I mixed in neutralized the salts?

Bill

You know, it was about a yr. ago I started w/ chc & I don't remember then about cation exchange either. All I did was rinse! Once in a while I added epsom salts when watering because I heard it was good for chc & to help plants take up nitrogen (I think).
Patty

I never did the exchange either for the cal. It's fine, better than fine! And when preping my chc's for the Meyer, I only used epsom, no calcium nitrate. I think I picked up on the calcium nitrate use the day I was done the whole process!! I'm taking my chances with this though, I'm not doing it again!

Haven't transplanted the meyer yet. I want it to drop it's last huge fruit from last year before I do.

Thanks for the info y'all. I am glad to know I am not the only one who didnt know about the cation exchange! I went out and got some epsom salts, so I think I will use just the epsom salts for now (potassium nitrate is on the way!). The only thing I have that seems to not be doing so well is my spearmint. I have been checking out descriptions of magnesium deficiencies and I think that it is showing signs of it. I have used Clearex on the plants I have already potted and I think I will give the spearmint a dose of epsom salts to see if that helps.

But I am gonna wait til I get my potassium nitrate before repotting my thai lime and bay tree. They are too expensive to replace!

Thanks,
Lydia

There's plenty of potassium nitrate sold as rocket fuel at eBay. The price are quite prohibitve for me. $20 for a 10-lb bag plus shipping. Anything that's more than $1 per lb of nutrient for me is out of my sanity.

This CHC thing is getting confusing. I think it started out with just rinsing & soaking,.. & then using epsom salt,.. & now it's soaking in dolomite & calcium nitrate & S.T.E.M. & epsom.
Lydia, now you say you are waiting for potassium nitrate!!! That's a new one (?) Maybe I didn't read enough here.
Don't kill your plants with kindness! I grew spearmint outside & never fertilized it...ripped it all out as it was spreading too fast. Can you plant it outdoors?
I have 2 nice bay trees too (potted, & am propogating 2 branches) & I rarely fertilize them. I only water them when they are dry &, they are in well drained soil (lots of perlite). I find that herbs are not heavy feeders.
What is clearex?
Also, don't repot if you don't have to w/ bay tree. Mine is in a 5 gal pot & probably rootbound but it loves it that way.
Patty (still curious about the potassium nitrate!)

The need for cation exchange and the rinsing depends a lot where you purchased your CHC. I purchase all my CHC from the Crystal Company of Saint Louis. The Crystal Company pre-rinses and then squeeze (IMPORTANT) dries all the CHC that they sell. For cation exchange, in the last rinse, here is the rates. I soak/rinse my CHC's in 55-gallon drums of water at a time. 55-gallons requires 4-Oz. each of Calcium Nitrate, and Epsom Salts. One gallon batches require 4 grams Calcium Nitrate (NOT Potassium Nitrate) and 4-grams Epson Salts. The cation exchange can be VERY IMPORTANT. Alan, if you cannot find any Calcium Nitrate, I will be happy to send you some, it does not take much. I purchase Calcium Nitrate in 80-lb. bags. Just let me know. - Millet

Did I say potassium nitrate? I meant calcium nitrate! (I guess I shouldnt drink beer when posting ). Millet, thanks for offering to send me some. I already ordered it from the same place that Benny got his and it was shipped yesterday. I ordered 2 pounds. That should keep me awhile.

Patty, my bay tree is still in a nursery pot and probably has been since last season (I bought it earlier this year). Whatever they have it in doesnt seem to be draining too well. So it definitely needs a repot. But once I get it into CHC I am hoping not to repot for awhile. I dont want it to get too big! My mint did great last year but since I repotted it in CHC (un-cationed) , it has had a number of problems. I cut it back due to spider mites, and it grew back pretty pale looking and the lowest leaves are yellow. No green veins or anything, just yellow. I fertilize my herbs pretty sparingly in general but the mint definitely needs something. Not sure if it is just more N or if it really is magnesium deficiency. Clearex is a product that is supposed to help leach salt from your pots. I am gonna use it on the plants that I already potted.

Millet, I got my CHC from a local orchid grower who gets her CHC from the Chrystal Co. She washes them before bagging. But just to be on the safe side, I washed them again, and now I am gonna make sure I do the cation exchange thing.

Well, thanks for all the help y'all. I actually have a few more questions, but I better go to bed before I start talking about potassium nitrate again!

Thanks again,
Lydia

Thanks for such a quick response Millet & Lydia.
Lydia, not all plants do better in chc, They are good with ccitrus, but I wouldn't use them with your bay tree or other herbs.