Dolomite lime and hard water???

[Chomp]

I have hard water with calcium already at high levels in it. Is there any need to add dolomite lime in soiless mixes without amended fertilizers IF you pH balance every watering and there's already calcium in it?

I want to use:

LC’s Soiless Mix #1:

5 parts Canadian Sphagnum Peat
3 parts perlite
2 parts mushroom compost

These ingredients are readily available and cheap in my area so it's what I'm using. I just don't see the point in adding a ton of calcium to the mix when I will be adding a ton of calcium when watering

Anyone with some knowledge in this arena feel like handing some over to me?

Thanks,
Chomp

 

[Chomp]

Cricket Cricket Cricket....

 

[redneck shogun]

Mushroom compost does seem to be readily available in most places around here but they are probably bunk. In fact I started my first organic grow exactly as you are planning. I tortured those plants until they dried under the light. If I had just went with EWC and powdered dolo that first run would of done fine. I wasn't experienced enough to know what I could alter in that mix and unless you do I would advise not to deviate from LC's mix. And yes the greensand is important too.
I grow many things in containers besides cannabis and I personally like to run something like alfalfa through my mix the first time to get it going. I only use dolo that first time then I never throw that soil out it and it goes into my recycled bins.
I can't imagine ever balancing my water like I did in hydro. What a huge unnecessary headache.

 

[Scrappy4]

I spoke with the owners daughter at lambert peat (spag)of Canada recently. She said their regular unaltered peat runs 3.5-4.5 ph but is almost always 4. I have zero idea of the mushroom compost, or if your peat has added lime, as some do. But, most likely you will need to add lime. And if you skip or go light on the lime make sure you provide some mag in some form. good luck.........scrappy

 

[Chomp]

The issue is the calcium that's in my water and the calcium in the dolomite lime. I've used the mushroom compost before without problems so it's not "bunk"....

The problem I am trying to avoid in this soiless grow is the pH problems and nutrient lockout that would come with way too much calcium throughout the grow. Which is what I suspect to be the problem I am having with my plants at the moment.

Just trying to get opinions from someone else that may have had the same problem or knows what they are talking about from experience.

I am plenty experienced growing hydro, soiless, organic, coco...but my water pH has changed since my last grows and it's causing problems that I believe to be stemming from too much calcium. RO water is not an option and neither is buying water

Chomp

 

[VerdantGreen]

i am in the same situation, and i still add the dolomite lime to the soil. i also pH balance my hard water (to around 6 with citric acid) - and it works just great. many organic peeps will tell you that pHing is unnecessary, but in my experience it is a good idea if you have hard alkaline water. everyone's situation is different as are their inputs

good mushroom compost is fantastic stuff. i used to use it as the only compost in my mix, also at 2 parts in 10, and got great results. you want to find some that has been standing for a while.

VG

 

[Chomp]

Thanks VerdantGreen...

I usually get the bagged MC and mix up the ingredients/hydrate it and let it sit for a couple weeks to a month before I use it. I always pH the nutrients also usually with white vinegar to avoid the extra salts in pH up. I haven't used citric acid before...good stuff?

Thanks again,
Chomp

 

[Chomp]

What I was wondering is if when I hydrate the medium initially when mixing it up the pH of the mix is usually around 6...This last time the pH was over 8 so the extra lime would be working against me in this sense right?

Chomp

 

[VerdantGreen]

the thing about lime is that it will neutralize acid but not lower the pH if it is above 7 - so it makes sense to make sure that you are watering with something slightly acidic/below 7 - then the lime will do its job and neutralize that acid. given that many nutes are best absorbed at 6-7 this makes sense to me. of course good organic soil has plenty of buffering properties of it's own but i dont think these are enough to negate the potential problems with a very alkaline water source. i have never had a problem with too much calcium tbh, i should check out your grow.

there is a thread about citric acid. it has positives besides being acidic. ive never used vinegar but i imagine it is a stronger anti-microbial than citric.

p.s. lime can often be added to mushroom compost so you might want to check that it isnt for yours.

VG

 

[VerdantGreen]

not sure why your pH was over 8, the dolomite lime shouldnt take it much above 7 so you should use pH'ed water and check that the lime is correct etc

 

[Chomp]

not sure why your pH was over 8, the dolomite lime shouldnt take it much above 7 so you should use pH'ed water and check that the lime is correct etc

That was when I first mixed it up. My well water's pH went way up on me for some reason. It used to be pretty neutral and I never bothered to pH it when hydrating and mixing the medium up. Now the tap water is over 8 and I have been pHing it down to 5.5 to 6.2 when watering.

But I never expected that the medium would be affected that much by the initial hydration.

I mixed up a new batch with pHed water without lime and transplanted the problem plants and they have recovered from the problems. The pH of the soil is about 6....hard to really tell exactly with the soil test kit....but it's not over 8 anymore....

This is what led me to ask the original question about leaving lime out of the mix if you have hard water with a lot of calcium already in it.

Thanks for the help,
Chomp

 

[Chomp]

.

p.s. lime can often be added to mushroom compost so you might want to check that it isnt for yours.

VG

That's probably the part I missed....

Thanks again!
Chomp

 

[mad librettist]

makes sense to me. if you have too much of something good it becomes pollution. Especially in cramped containers, I imagine plants are very sensitive to pollutants.

 

[VerdantGreen]

i did think about missing out or reducing the lime in the soil mix (along the same way as what the OP says) but i opted to go with the added insurance of the dolo because i was already pHing the water. my pH is almost 9 .

ive always seen the extra cal and mag from my hard water to be a bonus to my grow and my plants all seem to like it - right across the scale from sative to indica.

 

[Iron_Lion]

the thing about lime is that it will neutralize acid but not lower the pH if it is above 7 - so it makes sense to make sure that you are watering with something slightly acidic/below 7 - then the lime will do its job and neutralize that acid. given that many nutes are best absorbed at 6-7 this makes sense to me. of course good organic soil has plenty of buffering properties of it's own but i dont think these are enough to negate the potential problems with a very alkaline water source. i have never had a problem with too much calcium tbh, i should check out your grow.

there is a thread about citric acid. it has positives besides being acidic. ive never used vinegar but i imagine it is a stronger anti-microbial than citric.

p.s. lime can often be added to mushroom compost so you might want to check that it isnt for yours.

VG

very true, I use bagged soil that comes ph balanced with oyster shells and dolomite but I still add 3-4 tbs per 20 gal of soil.


Last run I went heavy with dolomite and added 8tbs to my mix and had major burning on all my plants, yield still kicked ass tho. My tap water is 7.0 and Im not sure whats in it but it leaves a white crust around the faucet, Im thinking it has heavy lime content or something.

I pH all my water to 6.4 before use and havent had any problems since. I agree, even with organics ph is important because if I dont pH my water I get noticable problems popping up within 24 hrs.

I use apple cider vinegar, and have used it for years and never had a problem, I even use it to pH teas.

I have a well and my pH sometimes changes after heavy rains etc...for those with city water this may not apply because most water treatment facilities pH their water to 6.5ish before distribution.

 

[Chomp]

Well I learned my lesson and will pH everything from now on

I was just kind of stumped because I never had any problems like this even as a noobie using Miracle Grow soil and ferts years ago...lol

Maybe it was the finicky-ass DJ Blueberry genetics coming through in my Schnazzleberry#2 ????

IDK...they are making a comeback and I'm switching back to coco next transplant

Thanks for help and comments!
Chomp

 

[Sgt.Stedenko]

Chomp,
Dolomite is a carbonate rock similar to limestone. Limestone is calcium carbonate (CaCO3). Dolomite is similar but the calcium is replaced by magnesium and/or calcium (Mg/CaCO3). The ratios of Mg and Ca vary depending on the source of the dolomite.
Cannabis is a Mg loving strain, so adding dolomite lime boosts the Ca and Mg and buffers the pH of the soil mix. I also have hard water (limestone aquifer) and I add lime just to keep my soil buffered.

 

[Chomp]

Just want to say thanks again for all the information and help you guys give out...this place really is the new OG as far as I'm concerned...

Chomp

 

[VerdantGreen]

chomp i would be wary of changing mediums in the middle of a grow. coco is less absorbent than most soil-less mixes and you may find you have watering problems. i would try and see it through with the same soil mix.... but you may be just fine.

 

[whodair]

yes i homie i amend w dolomite, and have tap water that is fairly hard...sometimes i add calmag as well ...

my results are fine without ph-ing too, the plants seems to love the acidic nutrients and buffered medium !!