Hi All,

I have a pretty silly question. I have been growing for quite awhile and I have never beern in this predicament. I grow with 5 parts coco coir, 2 parts worm castings and 3 parts perlite. To each gallon of prepared medium, I add 1.5 tablespoons of dolomite lime. This medium works great and I have never ever had a problem with it. I usually reuse the mix for 2 grows. On this grow I am on now, the soil medium is on its second use. A friend of mine was mixing the soil for the kids while I was away. I just found out that he added more dolomite lime to the medium. I am now pretty sure this is the problem. I never check my ph when adding nutrients and I never really need to check my runoff. Well I have 3 ladies in week 1 of flowering and they are showing all sisgns of P deficiency. So I finally did a PH check of the nutrients before adding them to the medium and it is 6.5 and the runoff is 7.5. This is causing all the leaves to curl down and show purple between the veins of the leaves. I can not transplant to a new medium since they are all well rooted and in 5 gallon buckets. So I guess the question is.. Do I just lower the ph of the nutrient to 5.5 - 6.0 and hope I get a lower runoff? I know I can't add anything additional to lower the ph of the soil while the dolomite lime is in there and that has raised the PH. I wish my bussy would not have done that. (add the dolomite lime), but he thought it was needed everytime (not just on new preperations of soil). My plants are really struggling with this and I don't want to overdose them. Any suggestions on how to make the medium in the PH range of 6.0-6.5 at least on the runoff. Thanks in advance.

42 people have viewed this and no one has replied.. Hasn't anyone ever had this situation before and can give me their advice. I need to feed them again later today and would appreciate some real advice before proceeding.

Heya Patch , my advise leave um as they are , 1 week in flower have they had any bloom yet ? maybee there askng for some P , ? pictures , patiance and profile goes a long way on here , how did you accurately check the run off from the rootball by the way ?

bit of a tough one

id probly feed with a low ph or high which ever way round it was

Thanks for the reply. I use a Hanna PH GroCheck HI 981408 to check . I have searched and searched and I believe my only chance is to add lower ph'd nutrients to hopefully bring down the soil ph. I was thinking of ph adjusting the nutrients down to a ph of 5.5 and hoping the soild comes down to the 6.5 range. I am using biobizz only by the way. The leaves are getting pretty bad. This issue began in veg and is getting worse. I just didnt check ph until a few days ago and the issue was progressing. I am not going to leave them and let them fix themselves.. that won't happen, they are having an issue for sure.

Heya , its an pretty hard to check the root ball anywhere near accurate to be honest , the is an explanation by Ot1 on this board some where , and you being in such organic goodness the breakdown process should really buffer quite a high range of ph , imho , not ideal i no , sometimes my water is as high as 9.2 and ive never adjusted it to this day in any compost .
If i were you i would stick a few pics up in the sick plant section etc maybe more joy over there.

Thanks for the reply. I don't have a camera to take any pics. The leaf tips are pointing down and the fan leaves have a dark purplish spreading from the veins out. It is getting worse. Leaves are showing deformites/crinkle. Do you think I should adjust my nutrient ph down to 5.5 before watering tonight and hope the runoff is more in the 6.5 range versus 7.5 range?

Ok, this is just an fyi for everyone. I just watered the plants. The ph of the nutrient solution was 6.5 before I made any ammendment. I used PH Down and adjusted the nutrient solution all the way down to 5.7. After the feeding. The runoff is still locked in at 7.5. So I guess dolomite lime will hold that at that ph indefinitley. Oh well, I thought I would let people know that if you add too much dolomite lime, nothing will really bring it down fast.

5 parts coco coir, 2 parts worm castings and 3 parts perlite.


what makes you use this mix mate

Hey Jiffa,

I have been using it for 8 yrs now and I LOVE it!!! I found it on overgrow way back in the day and it was specifically talking about throwing out your ph checker and growing without checking things.. It has worked great as long as someone doesn't try to ammend what isn't broken. The mix is 5 coir, 2 worm castings and 3 perlite and than 1.5 tablespoons of dolomite lime per gallon of mix. At the correct application, it locks the runoff ph in at abput 6.4 -6.5. This is the best soiless medium I have "tuned" into and have kept it ever since. This is howerver the first time my buddy tinkered with the soil and added more lime when it wasn't needed. He thought evertime it is reused, the dolomite lime is needed and that is just so not true. And unfortunately, he didnt tell me he added more lime to the mix and I was watching the plants freak out abit and did all sorts of checking until I figure out the issue.

everything I have in my mix and my nutrients are 100% organic including the dolomite lime. So I was just curious why this was moved to a non organic forum?

try an AACT it may be a bit of a fuck about but it works wonders,
25ltr bucket or similar filled with water and left for chlorine to go, couple of hours with air stones should do it.
You want a minimum of 3 air stones at the bottom and a good strong pump, add 4 cups of worm castings and 2 table spoons organic molasses (holland and barret). Bubble away for about 36hrs keeping an eye on it and give it a stir now and then, after a day it starts to froth up, a good sign wait a lttle longer tho, go for the 36hrs. Give them a feed with this at 50/50 dilution and filter some into a pump up sprayer via a sock or pair of tights, give them a good spraying above and below leaves at a low pressure, leave the room have a cuppa read the paper. Go back in an hour and pick your jaw up off the floor!
As the sheriff says it's hard to get an acurate ph as it's constantly changing in the rhizosphere, if you want to drop the ph in the above brew then use organic lemon don't use any chemicals or ingredients with preservatives in, a second spraying a few hours later will add again. The brew won't last long a few days and it's peak will be around 24-36hrs depends how good your brewer is. Give it all a good clean and store it because it will be your best grow tool!

Were the worm casting taken from the worm without harming the worm? Perhaps this is why

Try doing a search on flushing. I'm not sure if it would work with lime but as a last resort you can use it to flush out any unwanted salts/ferts from your medium. I think the ratio is about 3-4 times the volume of your pots of pure water, ph adjusted and literally run through your medium to flush out the excess.

flushing is a last resort tho. Try that tea that I-zimbra has suggested first, most likely tho you will need to get the ph back to normal.

might be a good time to take some cutting if you havnt already mate.

I've had the opposite in that the compost was too acidic (well suspected to be, I had no way to measure it).

What I did was to replace the compost. To do this, start by removing the plant and rootball from the pot and dip the rootball in a large container of water. You can then remove the compost under water by shaking and teasing the roots. When done, with one hand hold the plant with its roots back in the plant pot roughly in the right position, then sprinkle fresh compost in. Water when done.

Heya , i use aact , minerals , kelp etc to gently change self prescribed symptoms over chemically adding Ph down every time , bloody simplest idea from Hairy i didn't even consider but personally i would have to be very upset with the compost and be at a last resort .

I have already tried the flushing. I did the 15 gallons of water per 5 gallon grow bucket. The PH has not budged. I suppose it is difficult to flush away dolomite lime that has an active life span of several years. As far as the worm casting brew, no need they are grown in a mixture of worm castings and are fed biobizz. And last but not least, lowering the ph of the nutrients does not work. I tried it.. I put in 5.5 adjusted nutrienst and the runoff stays locked in at 7.5. The issue was that too much dolomite lime was added to the mix.. So I suppose the lesson is... add only the required dolomite lime.. Over do it and you will lock out the nutrients to your plants.

what is aact?

Actively Aerated Compost Tea

Oh, Thanks you for the clarification...

What does that have to do with the topic?

worm castings are full of shit hot stuff that's why you've been using it for 6 years. By using it in an AACT your growing the shit hot stuff into massive amounts, it's a natural 'booster' that pisses all over any other! It won't change your ph permanently but it will get the plant back on track and the plant controls the rhizosphere so it's a start. Another possible, tho I wouldn't know really, would be to nuke the soil with chemical feeds and turn your mix into a hydroponic medium and treat it as such. But I would try the tea, I wouldn't uproot your girls a week into flower unless you accept they're headed for the bin

Thank you very much for the clarification...

no problem

worm castings are full of shit hot stuff that's why you've been using it for 6 years. By using it in an AACT your growing the shit hot stuff into massive amounts, it's a natural 'booster' that pisses all over any other! now i see!!! Nice work thank you I Zimbra

you are, first put 4 cups castings in the 25ltrs of water and add the 2 tbls molasses, there are 4 air stones on the go here.
Click to view attachment

a day and a half later it should look like this
Click to view attachment
ive had a feed out of this one by the looks

i put too much lime in my compost ix once, ended up with massive micronute lockout, suprised it's P def you're getting as the macronutes remain available at the higher ph's and micronutes get locked out, should be seeing things like iron and zinc def were the first to show up for me

take a look here and see which matches.

http://www.greenmanspage.com/guides/plant_abuse.html

you might try and feed with the particular nutes you're deficient in, but i don't think it'll help to be honest, if your runoff is 7.5, the actual ph may be a fair bit higher once it's had time to completely neutralize the acid's in the ferts totally. i think with your mix though, it's more the quantity of calcium and mg locking out P if it is a P deficiency, as 7.5 isn't that high, and there's no other bases in your mix to raise the ph higher than the ph of the dol'lime. maybe try a chem PK solution that'll deliver the stuff in a readily available form so less reliant on soil ph, they're usualy buffered to remain soluble in high/low ph's too

the way i got round it was to cull the plants and start again i'm afraid, as anything that will be strong enough to lower the ph to an acceptable range will react with the lime quite violently (well violently for a nice soft white piece of root) and probably just cause even more damage

Thank you for the input scragler. I do have this stuff in liquid form called Alaska Iron & Zinc in cheleated liquid form. It says not to use with standard nutrients (use alone). I haven't added it. Today is feed time again. The striping is not spreading so I don't think I should add it art this time? Any thoughts?

I don't think you have a bad pH problem yet. True, it's a bit high and could do with coming down but it's not panic stations. That purpling sounds like phosphorous deficiency all right but it's unlikely to be the high pH. If the lime and phosphorous fertiliser were dumped on top of each other in their solid forms you might lock the P out but not usually otherwise unless the pH is way over 8. The normal reaction in high pH is to lock out the trace elements and the leaves go mottled or yellow. Is your nutrient solution above 15oC? Cold will make them go purple as they can't take the P up. Make sure your nutrient has adequate P. Basic , I know, but some nutes are a bit low.
Remedies.
Lower your pH to 5 every time you water. This will give a zone of lower pH for a while so the plant can uptake the trace elements. Personally, this would be my choice.
You can go to the local nursery, garden centre or hydro shop and buy some flowers of sulphur. Sprinkle a teaspoon of that around the top of yor pot. That will counteract the lime over time.
A more drastic measure is to dig a hole in the root zone (use a piece of pipe and drive it into the soil and pull out a plug of soil), fill it with coco coir and feed the plant in that area. Use some Regenaroot from Canadin Xpress (or something like it-it's the only one I have experience with)to get the roots growing again.
Hope this helps.

where's the striping/yellowing etc occuring? if it's a micronute lockout, it'll be specifically on the new growth to start with and around the tops around the growth tips, P def will be the fan leaves at first

All the new growth and upper leaves are green. About 6" below the top is where the main big fans leaves shoe tiger stripping. They are greening up a little since last week when I sprayed them with epsom salts. The new upper growth is fine. Several of the main bigger fan leaves are cupping and stripping, but it seems to have slowed down. It could be because they are 11 days into 12/12 now and are throwing all their energy into rapid growth. There are no signs of lacking any issues with the stretch.

I have recently switched from using just coco to the following mixture.

35% coco
35% good quality peat
20% perilite
10% worm castings
handfull of bat guano to each pot
& I start adding nutrients once in 12/12

I read up a bit and quite a few people are using this method with good success. Including the guy who runs big buddha seeds, he reckons this mixture will out perform using just soil or coco on its own, so i thought why not? Let's give it a shot. Oh, nrly 4got 2 mention, there's a layer of clay pebbles @ 5-10cm deep @ the bottom of each pot, the above mix goes on top

oh right, doesn't sound like a problem with ph then. first thing to show is iron def i've found, although this is in compost, but it should remain true for all mediums, just sounds like Mg def like you say. wouldn't worry about it if epsoms has stopped it spreading

That sounds very much like Mg, without pics it's difficult.

I see that you have sprayed with epsoms but maybe putting a little in your feeding water as well on the next feed.