When you put your plant in a pot the compost or soil will feed your plant and give it the protection it needs to grow healthily.
As a rule of thumb outside soil is generally more alkaline in drier areas whereas most soils tend to veer towards the acid side.
Checking your soil by its pH reading.
When the Potential Hydrogen Ions or (pH) values are measured you can find out what condition your soil is in.
If the value of the soil is below pH 7.0, the soil is described as acidic (acid) and when the soil is greater than pH 7.0 the soil is described as alkaline or (base).
to give a little more detail an acid is sometimes defined as a solution with the potential to donate a Hydrogen ion, or to accept a Hydroxide Ion from a base.
A base on the other hand is sometimes defined as a solution with ability to donate a Hydroxide Ion, or accept a Hydrogen ion.
Low pH corresponds to a high hydrogen ion concentration and vice versa, while a high pH corresponds to a high Hydroxide ion concentration and vice versa.
Plants need the correct pH balance to grow healthily and if the ph is incorrect the plants roots may refuse to take on the correct nutrients causing the roots to lock out the desired balance.
Some examples of pH values in plants and vegetables
Artichoke pH 5.6 - 6.6
Brussels Sprouts pH 6.0 - 7.0
Cabbage pH 5.6 - 6.6
Cannabis pH 6.5 to 7.0
Carrot pH 5.0-6.0
Cauliflower pH 6.0-7.0
Celery pH 6.0-7.0
Chili pepper pH 5.0-6.0
Chives pH 5.0-6.0
Cucumber pH 5.0-6.0
Garlic pH 5.0-6.0
Leek pH 5.0-6.0
Lettuce pH 6.5-7.0
Mint pH 6.0-7.0
Mushroom pH 7.0-8.0
Onions pH 6.2-6.8
Parsley pH 6.0-8.0
Parsnip pH 5.0-7.0
Peas pH 5.6-6.6
Peppers pH 6.0-8.0
Potato pH 5.8-6.5
Raspberry pH 6.0-6.5
Rhubarb pH 5.0-7.0
Shallots pH 5.0-7.0
Spinach pH 5.0-7.0
Strawberries pH 6.0-7.0
Sunflowers pH 6.0-7.0
Tobacco pH 5.0-7.0
Tomatoes pH 5.5-7.0
Turnip pH 5.0-7.0
Here are some examples of natural and household items and their pH values
pH 2.2 Lemon juice
pH 3.6 Orange juice
pH 4.4 Beer
pH 5.6 Pure Rain
pH 6.6 Milk
pH 7.0 Distilled water (H2O)
pH 8.0 Seawater
pH 9.2 Baking soda (NaHCO3)
pH 10.6 Milk of Magnesia (Mg(OH)2)
pH 11.4 Household ammonia (NH3)
pH 12.8 Household bleach (NaClO)
Any medium that is going to be used to grow any type of plant has to be within a certain range of the pH scale.
The soil, nutrient solutions and water all need to be monitored and adjusted to stay within a specific range, depending on your method of growing for example ranges will vary between soil and hydroponic growing
When a plant's soil or nutrient solution becomes too basic the nutrients become unavailable to be absorbed by the roots.
When the soil or nutrient solution becomes too acidic the acid salts will chemically bind together the available nutrients and they will be non absorbent by the roots.
When this happens the plant will show tell-tale signs of stress which can look like the plant needs more nutrients.
Beginner indoor garden and seasoned growers can fall prey to this by adding more nutrients and causing a toxic salt build-up.
Toxic salt build-up stops the roots from absorbing water.
So remember as a rule of thumb to always test the pH before reducing or increasing a fert or nute dosage!
The pH of your soil or hydroponics set up can be measured with a simple pH Tester, or small one time paper tests.
These are highly recommended when growing any plant.