How Do I Use Nutrients and What Do They Do?

So, you're looking to make the most out of your plants… Well, we got you covered. Below, you'll find possible plant symptoms and what they might mean, as well as what each nutrient does.

Nutrient and Deficiency Table

To use the table, match up the plants symptoms with those on the table. Nutrients that are shaded red are the problem.

Nutrient Deficiency Table

Nitrogen (N)

Pale plants, red stems, smaller growth. Rapid yellowing of lower leaves progressing up the plant. Add any chemical fertilizer containing N. Treated plants recover in about a week.

BC Northern Lights nutrients package tip: Change the ratio of base nutrients, cutting back on Flower and increasing Grow and Common.

Phosphorus (P)

Slow or stunted growth, red stems. Smaller leaves that are dark green. Lower leaves yellow and die. Add chemical fertilizer containing P. Affected leaves will not show recovery, but new growth will appear normal.

BC Northern Lights nutrients package tip: Our nutrients are generally fairly high in P and K, so deficiencies are extremely unlikely. However, if it is an issue, extra Super B+ would be recommended. The quality of the medium also has bearing when it comes to the availability of P – if it’s too high in Calcium, it can lock up the P. In this case giving Super B as a foliar would benefit your plant since it’s more readily available. Common is a better choice.

Potassium (K)

Affected plants are usually tallest and appear to be most vigorous. Necrotic spots form on lower leaves. Red stems. Leaves appear pale or yellow.

BC Northern Lights nutrients package tip: Add chemical fertilizer containing K. See above.

Calcium (Ca)

Lack of Calcium in the grow medium results in the grow medium becoming too acidic. This leads to Mg or Fe deficiency or very slow stunted growth.

BC Northern Lights nutrients package tip: Adding more Common is the immediate choice, but FHD has released a new product Calnesium which is a better choice for Ca deficiency since it also contains Calcium Chloride in order to keep the nitrogen values from getting too high and causing other problems.

Sulphur (S)

Plants suffering from S deficiencies exhibit yellowing of new growth.

BC Northern Lights nutrients package tip: Bud Boom is a good source of Sulphur.

Magnesium (Mg)

Lower leaves yellow and may even turn white while veins remain dark green. Blades die and curl upward.

BC Northern Lights nutrients package tip: Use Bud Boom, but Calnesium would be a better option.

Iron (Fe)

Leaves on growing shoots turn pale and veins remain dark green. pH imbalances make iron insoluble. Foliar feed with chemical fertilizer containing Fe or rusty water.

BC Northern Lights nutrients package tip: Flower is the best option for BCNL growers, however Calnesium has additional Iron and would be our first choice.

Manganese (Mn)

Necrotic and yellow spots form on top leaves. Mn deficiency occurs when large amounts of Mg are present in the grow medium. Foliar feed with any chemical fertilizer containing Mn.

BC Northern Lights nutrients package tip: Flower and Grow both contain Mn.

Boron (B)

Growing shoots turn grey or die. Growing shoots appear burnt. Treat with one teaspoon of Boric acid (sold as eyewash) per gallon of water.

BC Northern Lights nutrients package tip: Flower and Grow both contain B.

Molybdenum (Mo)

Yellowing of middle leaves. Foliar feed with chemical fertilizer containing Mo.

BC Northern Lights nutrients package tip: Flower and Grow both contain Mb, but Calnesium contains an additional source. This deficiency should be extremely rare.

Zinc (Zn)

White areas form at leaf tips and between veins. Occurs in alkaline grow mediums. Zn deficiency can be treated by burying galvanized nails in the grow medium.

BC Northern Lights nutrients package tip: Flower and Grow both contain Zn, but Calnesium contains an additional source.

How the plants use the nutrients you give them

It’s not only important to know how to grow but why the plants grow. What is it plants like that makes them perk up? Your relationship with your plant is like any other – you have to listen to them and know that they want.

Primary nutrients


  • Necessary for formation of amino acids, the building blocks of protein
  • Essential for plant cell division, vital for plant growth
  • Aids in production and use of carbohydrates
  • Directly involved in photosynthesis
  • Necessary component of vitamins
  • Increases foliage and plant vigor
  • Affects plant energy reactions


  • Facilitates photosynthesis, respiration, energy storage and transfer, cell division and enlargement
  • Improves quality of fruits, vegetables, and grains
  • Helps plants survive harsh winter conditions
  • Promotes early root formation and growth
  • Increases water-use efficiency
  • Stimulates plant metabolism
  • Vital to seed formation
  • Hastens maturity


  • Carbohydrate metabolism and the break down and translocation of starches
  • Activates enzymes and controls their reaction rates
  • Increases disease and cold resistance
  • Improves quality of seeds and fruit
  • Essential to flower development
  • Increases water-use efficiency
  • Essential to protein synthesis
  • Important in fruit formation
  • Improves winter hardiness
  • Increases photosynthesis

Secondary nutrients


  • Increases fruit set
  • Regulates plant respiration
  • Stimulates microbial activity
  • Involved in nitrogen metabolism
  • Essential for nut development in peanuts
  • Utilized for Continuous cell division and formation
  • Aids translocation of photosynthesis from leaves to fruiting organs


  • Improves utilization and mobility of phosphorus
  • Activator and component of many plant enzymes
  • Influences earliness and uniformity of maturity
  • Key element of chlorophyll production
  • Increases iron utilization in plants
  • Aids in seed germination


  • Aids in seed production
  • Integral part of amino acids
  • Helps develop enzymes and vitamins
  • Promotes overall growth and maturity
  • Promotes nodule formation on some plants
  • Necessary in chlorophyll formation (though not a constituent)



  • Essential for germination of pollen grains and growth of pollen tubes
  • Essential for seed and cell wall formation
  • Affects nitrogen and carbohydrates
  • Necessary for sugar translocation
  • Promotes plant maturity


  • Interferes with phosphorus uptake
  • Controls water loss and moisture stress
  • Enhances maturity of small grains on some grow medium


  • Intensifies color
  • Increases sugar content
  • Catalyzes several plant processes
  • Major function in photosynthesis
  • Major function in reproductive stages
  • Indirect role in chlorophyll production
  • Improves flavor of fruits and vegetables


    • Acts as an oxygen carrier
    • Promotes formation of chlorophyll
    • Reactions involving cell division and growth
    • Activator for enzymes that control respiration


    • Essential in phosphorous and magnesium uptake
    • Functions as a part of certain enzyme systems
    • Increases the availability of P and Ca
    • Aids in the utilization of nitrogen
    • Aids in chlorophyll synthesis


    • Aids in the formation of legume nodules
    • Needed to convert inorganic phosphates to organic forms in the plant
    • Required to form the enzyme “nitrate reductas” which reduces nitrates to ammonium in plants


    • Necessary for chlorophyll production
    • Necessary for carbohydrate formation
    • Necessary for starch formation
    • Increases leaf and fruit size
    • Aids plant enzyme system
    • Aids in seed formation

    In addition to the 13 nutrients listed above, plants also require Carbon, Hydrogen, and Oxygen, which are extracted from air and water to make up the bulk of plant weight.

    BC Northern Lights Nutrients packages

    Now that you know what each nutrient does and what deficiencies in them might look like, take a look at our premium nutrient blends to have total control over your plants.