Nitrogen (N) Nutrient Deficiencies In Plants

Nitrogen is one of the essential mineral nutrients that a plant requires for healthy growth. Nitrogen deficiencies are important to diagnose and fix.

Nitrogen (N) Nutrient Deficiencies In Plants

Nitrogen is one of the essential mineral nutrients that a plant requires for healthy growth, and unfortunately, is often in limited supply.

It is taken up through a plant’s root system from its growing medium, in both soil and hydroponic growing systems. Organisms in soils oftentimes use up all nitrogen reserves.

This leaves minimal amounts of nitrogen for the plant, and it becomes necessary to supplement.

Why Is Nitrogen Important For Plants?

Nitrogen is considered to be the most important nutrient, and plants absorb more nitrogen than any other element. Nitrogen is extremely vital in the health of our plants, because it is a major component of chlorophyll, the compound by which plants use their light source energy to produce sugars from water and carbon dioxide (photosynthesis).

Without enough nitrogen, our plants are unable to convert the energy from light, which is one of the biggest factors in enabling them to grow and thrive.

Identifying Nitrogen Deficiency In Plants

A nitrogen deficiency is one of the most common deficiencies found in plants. It initially affects the older, lower leaves, and they will begin to turn yellow in color.

Nitrogen is a mobile nutrient, wherein in can move around, and it is at this point that the plant is breaking down its last reserves in the old leaves, in order to transport it to the fresh, young leaves.

The nitrogen deficiency will progress up the plant and only the new growth at the top will appear to be green. The lower leaves will continue to turn yellow, wilt, and eventually die. Death of the leaves start at the tips and goes inward.

You may notice that new leaves are smaller in size, and overall growth of the plant is stunted. Plant cell tissue is made up largely of nitrogen, so overall growth of plants is affected quickly when a nitrogen deficiency is present.

  • Yellowing of lower leaves
  • Starting at the tips and working inward between leaf veins
  • Wilting or drooping
  • Older leaves affected first, often dropping off in severe cases
  • New growth appears stunted


Examples Of Nitrogen Deficiency



How To Correct Nitrogen Deficiency

The best defense, is to introduce simple ways to correct and prevent the deficiency in both soil and hydroponic grow systems.

One of the first things to take a look at is pH balance, in both soil and hydroponic growing systems. A pH imbalance will block nutrient uptake through the plant’s roots.

It is important to regularly check the pH, and to be sure to keep the pH within the appropriate range for soil or hydroponics. The optimal pH range for most plants is between 5.5 and 6.5. In this range, the nutrients present in the soil or water are soluble, and are easily taken up through the plant’s root system.

When the pH level is outside of this range, even when the proper nutrients are present, they are not able to reach the plant.

Are your garden pots or containers too small?

In soil growing, undersized containers for plants is a common mistake when growing indoors. Plants in undersized containers will quickly use up all available nutrients and won’t thrive. Re-potting plants can be done up until the third week of flowering.

Address the quality of your growing medium

Another easily correctable factor is poor quality growing medium. The importance of using quality grade horticultural soil, other mediums, or the highest quality water cannot be stressed enough. Do not use topsoil in which you are not certain about its nitrogen content.

Try a nitrogen rich fertilizer

Fertilizing and nutrient supplementation is very important when growing. Fertilizing on soil is necessary to boost plant growth, and a lot of plants tend to grow faster than their roots can gather natural nutrients in soil.

Many gardeners and growers like to have a ready-made supplement on hand to prevent or quickly remediate a nitrogen deficiency at the first signs.

All-in-one combined solutions give plants the added mineral and nutrition boost that they need, resulting in enhanced foliage growth and healthier and more productive fruits and blooms.

  • Verify growth medium pH between 5.5 and 6.8
  • Apply nitrogen rich soil or hydroponic nutrients or amendments


How Do I Know Which Products Are Nitrogen Rich?

The N-P-K numbers that are often displayed on the supplement will indicate the relative quantities of nitrogen, phosphorus, and potassium the product contains.

If you are searching for a nitrogen rich product, you will want the first number, or N number, to be larger than all the others. In the image above, the 12 represents the nitrogen number. If you aren't sure be sure to consult the product MSDS sheet to find out what it contains or contact our helpful experts for recommendations and tips.



What If I Add Too Much Nitrogen?

The first step is to not make things worse. Stop adding any amendments or nutrient supplements that were nitrogen rich. Make sure that your pH levels are within the proper specs and then flush plants.

A good rule of thumb here is 3 gallons of water for every gallon of soil. In a hydroponic garden this involves draining off your nutrient rich water and replacing it with pure water.

This should help to rid the grow medium of any excess nitrogen. It's important after this step to continually monitor plants and soil or water pH levels to prevent an imbalance.

Nitrogen is incredibly important for vegging. You need it to encourage robust, leafy growth. Do not get caught unprepared, especially now that you know what to look for!

Want to learn more about nutrient deficiencies?

Read our entire nutrient deficiency series as well as learning about micro vs macronutrients.


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