How to Fix Nutrient Deficiency in Plants
Gardeners know the pain of investing time and money into their plants only to find them discolored or in poor health. Often, these signs are a result of nutrient deficiency in plants. Growing robust plants requires feeding a balance of solutions with various micronutrients and macronutrients. If given incorrectly, plant health can suffer.
Below is a breakdown of plant nutrient deficiency and treating it with the right nutrients, supplements, and additives.
What Causes Nutrient Deficiencies in Plants?
Nutrient deficiencies in plants are often caused by imbalanced soils, poor drainage, or incorrect pH levels that block uptake. Over-fertilization can lead to salt buildup, locking out key elements. In hydroponic systems, issues like clogged emitters, improper nutrient mixing, or outdated feed charts can throw off ratios. Even with good inputs, inconsistent watering or media saturation can disrupt delivery and cause deficiencies.
How to Identify Nutrient Deficiencies in Plants
Identifying which nutrients your plants are deficient in is essential before attempting to fix the issue. The most common nutrient deficiencies are magnesium, calcium, and iron. Although calcium and magnesium are secondary nutrients, they’re required in larger amounts.
Since iron is a micronutrient, it can become easily lost — even by having the wrong pH. Even if you have all the right elements, if you have the wrong pH, you will have a nutrient deficiency. Hydroponic plants generally prefer a slightly acidic nutrient solution with a pH of around 5.8-6.3.
Most plant nutrient deficiencies are categorized in the below elements:
- Sulfur
- Magnesium
- Nitrogen
- Phosphorus
- Potassium
- Calcium
Symptoms of Nutrient Deficiencies in Plants
Nutrient deficiencies show up fast when your plants can’t access what they need. Common symptoms include yellowing leaves, slow growth, weak stems, and poor yields. Spotting these early is key—each deficiency leaves its own clues, which we break down below.
These elements are essential in plant development and growth because they provide the nourishment needed to thrive in an indoor artificial environment. Depending on the deficiency type, plants will show various signs, which we’ll break down below. Be sure to know which nutrients are deficient before adding more.
Nitrogen (N)
Nitrogen is one of the fundamental nutrients because it supports plant growth by promoting chlorophyll production needed for photosynthesis. Some signs of nitrogen deficiency in plants are:
- Yellow lower leaves may turn a wispy, pale white as the lack progresses
- Growth delays minimal growth and small leaves
Phosphorus (P)
Phosphorus is essential for root development, flowering, and energy transfer within the plant, playing a crucial role in DNA formation and cellular processes. Some signs of phosphorus deficiency in plants are:
- Dark green or purplish leaves, especially on older foliage
- Stunted root growth and delayed flowering or fruiting
Potassium (K)
Potassium regulates water movement, enzyme activation, and disease resistance, helping plants maintain structural integrity and stress tolerance. Some signs of potassium deficiency in plants are:
- Brown, scorched leaf edges and yellowing between leaf veins
- Weak stems and increased susceptibility to diseases and pests
Sulfur (S)
Sulfur is vital for protein synthesis and chlorophyll formation, contributing to the plant's ability to produce amino acids and essential oils. Some signs of sulfur deficiency in plants are:
- Uniform yellowing of young leaves while older leaves remain green
- Stunted growth and reduced seed or fruit production
Calcium (Ca)
Calcium strengthens cell walls and promotes proper root development, while also helping regulate nutrient uptake and enzyme function. Some signs of calcium deficiency in plants are:
- Brown spots or necrotic areas on young leaves and growing tips
- Blossom end rot in tomatoes and peppers, stunted root development
Magnesium (Mg)
Magnesium is the central component of chlorophyll molecules and activates many plant enzymes necessary for photosynthesis and metabolism. Some signs of magnesium deficiency in plants are:
- Yellowing between leaf veins while veins remain green (interveinal chlorosis)
- Older leaves affected first, potentially leading to leaf drop
How to Fix Nutrient Deficiencies in Plants
Fixing nutrient deficiencies starts with identifying the root cause—whether it's pH drift, salt buildup, or a weak feed mix. From there, it’s about adjusting inputs, flushing when needed, and dialing in your system. Here’s how to troubleshoot and correct the most common issues.
Alfalfa and Cottonseed Meal
Alfalfa and cottonseed meal are one of the best ways to treat a nitrogen deficiency in plants. It’s used as a dry soil amendment, and best applied when plants show signs of new growth.
Some signs of nitrogen deficiency in plants are:
- Yellow lower leaves — may turn a wispy, pale white as the lack progresses
- Growth delays — minimal growth and small leaves
Chelated Fertilizer
Chelated fertilizers, also known as chelated minerals, are bonded with organic matter. They’re responsible for making nutrients more accessible to the plant’s roots. Typically, liquid fertilizers use chelated minerals and target specific nutrient imbalances such as iron and zinc deficiency. They’re commonly used in both hydroponic and soil gardens.
Calcium Nitrate
Calcium nitrate is another nutrient solution for combatting a calcium deficiency in root growth. This element is essential for growing media as it affects adjusting pH in nutrient solutions.
Calcium nitrate is typically applied as a sprayed solution and should be added before the plants are added. Additionally, a second coat should be applied once the plant grows and flowers before producing fruit.
Compost Tea
Compost tea is popular for solving calcium and zinc deficiencies in plants, and it’s easy to see why. Compost tea uses high-quality compost to create a nutrient-rich liquid tea that can be used in hydroponic systems, at ground level to water plants, or as a foliar spray. It’s rich in beneficial microbes and nutrients and best added to the growing medium before planting.
Fish Emulsion & Meal
Fish emulsion and meal are excellent soil additives for addressing nitrogen deficiencies because they contain micronutrients. Fish emulsion is left over after the fish has been pressed for oil. Fish meal is made up of the inedible parts of a fish ground into a fine powder.
Both fish emulsion and fish meal are meant to enhance soil. The emulsion allows younger leaves on plants quick access to available nitrogen, and the meal provides a slow and steady nitrogen release.
Gypsum
Gypsum is a mineral that’s a hydrated form of calcium sulfate. It’s used for correcting sodium pH levels and is an excellent source of calcium. In addition to helping the plant’s nutrient uptake, adding it directly to the top of soil that has developed a hard crust will break it up and allow more water drainage.
Iron Supplements
Chelated iron is the most common form of iron supplement for plants. It should be added to plant tissue by itself, as any other fertilizer could cancel out the effects of the iron supplement. Iron deficiency commonly happens when the soil pH is off, as it can block the roots from absorbing vital micronutrients.
Magnesium Sulfate
Magnesium sulfate, commonly known as Epsom salts, has been an essential nutrient additive for ages. A teaspoon of magnesium sulfate in a water reservoir can address sulfur or magnesium deficiency. It can also be used as a foliar spray.
There are many ways that a plant nutrient deficiency can happen. However, when caught and addressed early, plants and their roots will unlikely sustain any permanent damage. Growers must be aware of the signs of nutrient deficiencies in plants and be familiar with the various methods of correcting them with organic matter.
Replenish Your Plant’s Nutrient Deficiencies Today
Many nutrients, supplements, and additives are available to help with nutrient deficiencies in plants. Some options include organic nutrients, synthetic, liquid, dry, nutrient sets, and boosters.
Ready to replenish your plant’s nutrient deficiency? Shop hydroponic nutrients, supplements, and additives at GrowGeneration today!
