What's the best range for ph levels in soil

Hello again everyone! Just have a quick question about ph levels. What’s the best range of ph for plants in soil? I’ve currently been watering with 6.8ph roughly for my blue dreams and white widows and they look very healthy.

6 to 7 for soil.



Honestly I suspect the ideal pH will vary based on growth stage, but in general aim for pH 6.5


6.3-6.8, with the sweet spot being 6.5.


The pH of your soil or potting mix can fluctuate as nutrients/salts begin to build up.
This happens most often when you are regularly feeding more nutrients than your plant can use.
I was watering my cannabis plants tonight, and I mixed in a half strength dose
of bloom nutes. So I test the PH and it is right in range, about 6.5. When I
tested the runoff, it was really acidic at around 5.5.
Checking the pH of your run-off water is an important step to diagnose problems with
the pH around your plant root zone. This step is especially important for new growers
and those who are having issues with nutrient deficiencies.

If the runoff pH is much higher or lower than expected, chances are you have unused
nutrients or salt build-up near the roots that are raising or lowering the pH of your root zone.

When this happens, you can remove this buildup by flushing your soil or soilless mix
with about 3 times as much pH’ed water as the volume of your container. You can also
flush your plant to remove extra nutrients if you’ve over-fertilized your plants and
they’re showing signs of nutrient burn.

This will wash away the buildup and help “reset” the pH of your root zone back to the proper level.

Some growers choose to flush their plants every 3-4 weeks regardless of whether they
notice problems to prevent buildup, though this is usually unnecessary unless you are
chronically overfeeding with nutrients.

After someone has been growing the same strain of marijuana, in the same medium, with
the same nutrient solution, etc. for a while, chances are they will become very familiar
with their growing style and won’t need to check the pH of their runoff water unless they
notice problems.

Show Me Step-By-Step: How Do I Check the pH of My Water?

NOTE: The the blue and orange pH up/down bottles you see at hydroponic growing stores
are not designed for organic growing. While some growers believe it is okay to
add pH up/down in small amounts after you’ve mixed your nutrients into your water,
other growers feel this may kill the microorganisms that make organic growing so effective.

If you’re an organic gardener and worried about using pH Up/Down, there are natural ways to
adjust the pH that definitely won’t harm your living soil.

A cool fact about pH:

The type and amount of nitrogen used in a nutrient bottle has a big effect on how much 

it will affect the pH of your water.

Using this knowledge, a smart grower could buy or mix up nutrients based on the current 

pH levels of their water so that their nutrients auto-correct the pH.

#2 Reason For Dying Leaves: Watering Plants Incorrectly

Ok, you have successfully made sure you’ve corrected the pH, and you’re still seeing dying
leaves, or leaves with problems.

Under watered marijuana plant is thirsty!

Chances are you have a watering/root problem.

When growing in soil or a soilless growing medium like coco coir, this is usually caused
by poor drainage, or over/under watering.

To properly water your marijuana plant every time, use this technique:

Every time you water, add enough that about 20% extra runoff water has drained out the bottom
(if you don’t have drainage holes, or if water isn’t draining, this needs to be fixed immediately
or you will run into lots of other problems).

After you’ve watered your plants with 20% extra runoff, then don’t water them again until the
growing medium is dry enough to stick your finger in to about your first knuckle without feeling

In hydroponics where you’re growing with your roots directly in water , a root problem doesn’t
result from over/under watering, since you don’t water your plants.

The problem in hydro usually results when plant roots start “drowning” because they can’t get
access to enough dissolved oxygen in the water.

The way to fix this is to oxygenate your water with an air stone, or otherwise get more oxygen
to your plant roots.

In both soil and hydro, you can also see signs of root problems because of a condition known
as “root rot.” This condition will give you brown, mushy, smelly roots.

Root rot is often the result of bad watering practices, high temperatures, or poor drainage,
but sometimes root rot can appear out of nowhere.

When this happens, a great cheap supplement that seems to completely decimate root rot is
Aquashield. There are also other root supplements that are more expensive such as Great
White and Subculture B, but I’ve always had the best results with the much cheaper Aquashield.

#3 Reason For Dying Leaves: Nutrient Problem

Ok, you’ve ruled out the #1 and #2 most common reasons for dying leaves. You may actually have a
nutrient problem.


Awesome! This all really helped. Thanks for all the information everyone!

As a newbie, I experiment after each weekly flush from 5.8 - 7 then adding more phosphate or potassium Just to see plant reaction to find that sweet spot. I believe each plant has its own genes(likes & dislikes) and you need to be in tune with YOUR plant.

If you read somewhere 6.5PH is best and you find your plant is suffering a deficiency then go down to 6.1 or up to 7 and see what happens. And change the nutrients if you want to. You want to find the PH for your plant before you start changing nutrients. It could be simply a case that your plant or uptake more nutrients at a different pH than the one that you currently on if you’re finding your plant has deficiencies. But if you stick to a pretty simple Regiment with your nutrients and ppm you’ll find what works. Play with your PH before you play with your nutrients.

The only way you going to learn is to play around with different ideas and try different things.

With that being said… all my experimenting is going to stop when I Flip to flower in 10 days. I’m going to stick to strict growing rules. I may experiment in the last 1 -2 weeks but that’s it.

Her colour changes from varies PH levels

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