When to add calcium and magnesium carbonate


#1

My sativa auto is done stretching and branching and buds are filling in.No color in hairs or trichromes just stacking buds
Some say adding calcium and magnesium can help tighten up bud stacking so nodes fill out or that it also helps plant later burn up all nutes during and after flush.

I have some ag lime would adding some of it in water add calcium or magnesium to my soil?
53% calcium carbonate,43% magnesium carbonate with 21% water soluble calcium and 13% magnesium.


#2

If I had pretty stacking, budding plants; I would do as I have been doing. Potassioum boost in flower is most umporatnt, for sweetness.

Cl Mag is always necessary, but not so much in late bloom, and especially, not as a substitute for potassium; What is best for producing sweet resins. :smiley:


#3

That is basically a PH up and is only good if the soil is getting very acidic, as far as I know. I have never heard of calcium or magnesium being used to boost anything in flowering.

I had left that one just for you Latewood, as I have less experience with soil additives. But you said what I would have thought as far as any benefits to flowering.

During flowering things can get extra acidic, maybe this is why you have seen this stuff recommended during flowering Edneedsmeds.


#4

Thanks very much,makes sense.
I didn’t add lime but did a good wash.
It’s strange for my soil ph’s at 7.0 but the run-off reads 5.0.


#5

You will get different readings at the top of the soil as compared to the bottom. The difference are cause by differences in the root development and roots do tend to grow down and towards bottom where more water may have been accumulating or staying the most moist in a pot. More root activity and metabolizing does mean more ion and anion exchanges and possibly more acid.

5.0 is way too acid, you don’t want it below 5.5 and preferably not below 6.0 for soil. There is a bit of a debate about the perfect range for cannabis in soil, I say the best range is 6.0 - 6.5 in soil with a 6.2 as ideal, now – after a bunch of new studying and information I’ve collected, however the older traditional thought is 6.5 - 7.0 for soil. Also it is thought very acidic conditions increase the amount of males and or hermaphrodites when grown from regular seed, and so 6.5 -7.0 is still likely best in the beginning for when growing a bunch of regular seeds. And 5.5 - 6.0 in hydro with 5.8 ideal. Soil can go up to as high as 7.0 or even a bit higher, certainly no higher than 8 and I’d start to get worried if it stayed there for a long time. But even staying at 7 in a good organic composted soil you likely would not have many problems. In hydro I don’t worry so much about it staying very stable day to day, as it goes above or below the 5.8 the plant will take advantage and take different nutrients that become more available at different levels, as long as you don’t go below the 5.5 or above 6.5, you normally won’t have much to worry about in hydro.

How are you getting the two different readings? A PH probe stabbed in the top of the container’s soil and a PH pen testing the runoff water?

You might need to be adding some of the ag lime PH up but I would add very very little to start with, especially if the plants look very healthy, if it ain’t broke, don’t fix it. Right?