soil buffer, and ph adjustments

[lilnug420]

i grow outdoors

i have a question about how soil buffers work, so i've been growing for a few years using terra canna professional which has a ph of around 5.8

i was told that soils have buffers that make it so the ph always stays the same, if that's so, what's the point of adjusting ph before watering? if the soil adjusts itself?


how long do these buffers last? do they get used up with time?


does flushing a plant use up the buffer? i wanna do a flush before up-potting my girls to get rid of excess salts, when i flush i usually run tap water trough the soil for half an hour or so, until the water comes out clear and not yellow


would this consume the ph buffer? i wanna flush before uppotting from a 3gal container to a 10 gal one, and then do another flush a week or so before they switch to flowering.

 

[Creeperpark]

There's a big difference between terra canna professional mix and outdoor soil. Alkalinity always takes precedence over everything else. You can't change that without also changing the soil quality. You grow outdoors and use terra canna professional. Do you put the mix in the ground or in the container and grow it outdoors?

 

[growsjoe1]

As for whether flushing a plant uses up the pH buffering capacity of soil, it's a debated topic among growers. Some believe that flushing can deplete the soil's buffering capacity, while others argue that it has no significant effect.

 

[Creeperpark]

As for whether flushing a plant uses up the pH buffering capacity of soil, it's a debated topic among growers. Some believe that flushing can deplete the soil's buffering capacity, while others argue that it has no significant effect.

The difference is a potting mix or soil. If you are using an indoor mix then yes the flush will lower the buffering capacity. If you are in soil then the pH will stay because of the makeup of the soil. The difference is soil-less vs soil. If I try to change the soil pH of the ground it never lasts.

 

[St. Phatty]

ocw.MIT.edu

Prof Drennan, intro to Chemistry, talks about Buffers, during the pH section.

 

[lilnug420]

There's a big difference between terra canna professional mix and outdoor soil. Alkalinity always takes precedence over everything else. You can't change that without also changing the soil quality. You grow outdoors and use terra canna professional. Do you put the mix in the ground or in the container and grow it outdoors?

in a container

 

[lilnug420]

The difference is a potting mix or soil. If you are using an indoor mix then yes the flush will lower the buffering capacity. If you are in soil then the pH will stay because of the makeup of the soil. The difference is soil-less vs soil. If I try to change the soil pH of the ground it never lasts.

is terra canna professional soiless? i'm not quite sure

 

[lilnug420]

i saw this chart online:


considering i'm using ph drops to mesure, so i'm never going to be very accurate, (i have 2 cheap ph meters, but i don't trust them too much, and i cant afford the professional stuff, and even if i did, i'm too clumsy and would probably drop it a month after owning it)

would it be ok if one time i water at around 5/5.5 ph and the other closer to 6/6.5ph?

so i would go trough all the ph ranges where the nutrients are available?

 

[MadMac]

hello,
do not mess with different PH ...
if you water and want to adjust the PH ...
for Indica & Hybrids 5.8 is ok ...
for pure sativa go little higher... 6.0 -6.5 PH...
if you want to test the soil ... there are easy test kit's for soil...
but you can also use this PH paper stripes to get a idea...
what cannabis doesn't like is swinging PH levels...
and yes garden soil buffers the PH ... and stabilise ...
the mixed soil in bag's ... does it too but not too long...
that's why some get lockout etc... if the PH is to low or high...
my tab water has 7 PH and i'll reduce it to 6.2 PH for sativa's ...
i'll grow also in soil but indoors and pure sativa's... 120+ day's of flowering ...
for this long time you really have to care ...
M.

 

[lilnug420]

hello,
do not mess with different PH ...
if you water and want to adjust the PH ...
for Indica & Hybrids 5.8 is ok ...
for pure sativa go little higher... 6.0 -6.5 PH...
if you want to test the soil ... there are easy test kit's for soil...
but you can also use this PH paper stripes to get a idea...
what cannabis doesn't like is swinging PH levels...
and yes garden soil buffers the PH ... and stabilise ...
the mixed soil in bag's ... does it too but not too long...
that's why some get lockout etc... if the PH is to low or high...
my tab water has 7 PH and i'll reduce it to 6.2 PH for sativa's ...
i'll grow also in soil but indoors and pure sativa's... 120+ day's of flowering ...
for this long time you really have to care ...
M.

isn't that what soil buffers are for? for example if you soil is buffered at 6.5ph. if you water at 5.8ph, it will slowly drift up to 6.5 from my understanding

 

[MadMac]

isn't that what soil buffers are for? for example if you soil is buffered at 6.5ph. if you water at 5.8ph, it will slowly drift up to 6.5 from my understanding

yes... true... but after time if you water all time with ph 5.8 it slowly goes down to 5.8 ... the buffer is not endless .... for short flowering indica or hybrids it will work but if you have the plant longer in same soil the buffer is gone after some time and you get lockout...
M.

 

[Creeperpark]

isn't that what soil buffers are for? for example if you soil is buffered at 6.5ph. if you water at 5.8ph, it will slowly drift up to 6.5 from my understanding

It will be until your buffer is used up. Thats why it's best to keep your pH inline with your buffer.

 

[lilnug420]

It will be until your buffer is used up. Thats why it's best to keep your pH inline with your buffer.

i see, terra canna professional recommends watering between 5.5-6.5 on their website


do you recon ph drops are precise enough? been using them for 2 years.... switch from cheap ph meters

 

[Creeperpark]

i see, terra canna professional recommends watering between 5.5-6.5 on their website


do you recon ph drops are precise enough? been using them for 2 years.... switch from cheap ph meters

Yes regent pH testing is preferred by some because the testing does not rely on electric conductivity. When the EC is very low pocket meters can miss read and give false readings. Anything with less than 100 ppm should be tested using regent testing.

 

[dirty-joe]

i grow outdoors
/CUT/

i wanna do a flush before up-potting my girls to get rid of excess salts, when i flush i usually run tap water trough the soil for half an hour or so, until the water comes out clear and not yellow


would this consume the ph buffer? i wanna flush before uppotting from a 3gal container to a 10 gal one, and then do another flush a week or so before they switch to flowering.

If you NOT over fertilizing there is NO need to 'flush' your outdoor weeds.
IMO all the talk about watering till X% of run off, is simply BS from the nute companies wanting you to wash it down the drain so you can buy more. I grew in containers on the roof top last 3 years, and NEVER wasted any water. My threads are not hard to find, one was just dug up.

And if your 10 gallon finishing pot is truly 10 gallons (and full), you have nothing to worry about. You can quite easily get half pound plants from 10 gallon pots.

Also you PH your water because that is what plants 'like', I use only rain water, which is 'just right' no need to mess with it.