Deficiencies in essential plant nutrients can reduce a plant’s ability to grow and produce. Some deficiencies can even cause discoloration, wilting and distortion of leaves.
Knowing what to look for can help you identify and prevent nutrient deficiencies in your cannabis plants. Understanding which of the 17 cannabis plant nutrients are required for healthy growth can help you ensure that your crops have the best chance of success.
Nitrogen
Nutrient deficiencies in cannabis plants are a common problem that many growers face, and they can be difficult to identify. Fortunately, knowing the different types of nutrients and the signs of deficiencies can help you identify and prevent them before they become problems.
Nitrogen, for example, is a key macronutrient that is essential for plant growth and development. Deficiency can stunt growth and cause leaves to turn yellow between the veins and lose their shape.
Nutrients are split into two categories: mobile and immobile nutrients. The former can be moved by the plant and are translocated from older to newer leaves.
Phosphorous
Phosphorus is one of the most important nutrients for cannabis plants. It plays a vital role in helping your plants grow and is essential for a plant’s ability to produce CO2 for photosynthesis.
It is also critical for regulating transpiration and the manufacture of chlorophyll, sugars and starches. A phosphorus deficiency will lead to slow growth, small bluish-green leaves and a poor root zone.
A phosphorus deficiency can often be avoided by using a product that has a higher phosphorus content. You can find phosphorus-rich nutrients in many gardening stores.
The pH of the nutrient solution or soil is another factor that can affect your plants’ ability to absorb nutrients. If the nutrient solutions or the soil is too acidic (lower than 7.0) or alkaline (higher than 6.2), nutrients will not be available to your plants.
Potassium
Potassium is one of the most important nutrients for cannabis plants. It is essential for flowering and helps keep plant stems strong.
Deficiency symptoms include dull, pale leaves that become brown and burnt on the tips and edges. The veins on the inside of the leaf remain green.
If you’re growing cannabis in soil, monitor your nutrient solution and run-off regularly to determine if it is too high or too low in potassium.
If the run-off reads too low, your nutrient solution may need to be changed. This is an easy way to prevent a buildup of bacteria or fungal growth that can attack your roots.
Magnesium
Magnesium deficiency in cannabis plants can cause discoloration and stunted growth. In addition, magnesium deficiencies can negatively impact flower production.
Magnesium is a nutrient that is mobile and can be translocated from older leaves to newer ones as the plant grows. If your cannabis plant begins to show signs of magnesium deficiency, the first place to check is the bottom leaves of the plant.
If the lower leaves begin to turn yellow, your cannabis plant has a magnesium deficiency. The plant will eventually die if the deficiency is not addressed.
Boron
When growing a cannabis crop, identifying and preventing nutrient deficiencies is critical. This is because if you spot these issues early, it will be easy to solve them before they can affect your harvest.
Boron is a very important nutrient for your plants as it helps them develop their flower buds and leaves. It is a semimetal that is needed for plants to grow and can be found in many foods including fruits, vegetables and some grains.
A boron deficiency can lead to leaf septoria, a disease that shows up first on lower branches of the plant and causes a rough yellowing of the leaves. It is a common problem for growers using fertilizers that have a high salt content.
Calcium
Calcium is a crucial secondary nutrient that helps individual cells communicate and form strong cell walls. It also plays a key role in root development and strengthening plant roots.
When calcium deficiency is present, cannabis plants are likely to suffer from reduced growth and weakening branches. This is especially true for new leaves, which may grow weak and curled.
The first symptoms of calcium deficiency in cannabis plants are brown spots or blotches, and they travel gradually throughout the plant over time. In severe cases, these blotches can appear purple or yellow.
If you see these signs of calcium deficiency, you should take steps to fix it. One way to do this is to make sure the pH level of your growing medium is properly balanced. You can do this by using a good pH meter and testing both the nutrient solution and the runoff water.
Copper
Copper is an essential micro-nutrient that is vital for photosynthesis and enzyme production. It also helps metabolize carbohydrates (sugars) and proteins.
A copper deficiency in cannabis can cause a number of different symptoms, including yellowing of young leaves, a metallic glass-like appearance to the central part of the leaf and malformations on older leaves. In most cases, these signs will only occur while the plant is still growing, so it’s important to identify and address these issues as soon as possible.
Deficiencies are generally quite uncommon and often require weeks of observation before the symptoms appear. A common reason for deficiencies is when the pH of a medium or hydroponic solution is too alkaline for the roots to absorb. This can be fixed by flushing the grow medium with water that is pH balanced. It’s best to check the pH of your growing solution at least once a week, and adjust accordingly.
Iron
A nutrient deficiency can cause stunted growth, weakening of the plant’s leaves and stems, reduced flowering and lower yields. Identifying and preventing nutrient deficiencies is essential for maintaining a healthy cannabis crop.
There are many different types of nutrients that cannabis plants need for health and growth including nitrogen, phosphorus, potassium, magnesium, iron, copper and manganese. Knowing the signs of nutrient deficiencies can help growers diagnose the problem and make necessary adjustments to their grow environment.
The most common type of nutrient deficiency is nitrogen, and it can be seen in the form of yellow or brown leaves. Nitrogen is essential for enlargement and division, photosynthesis, and energy transfer and storage.
Manganese
Manganese is an essential micronutrient that cannabis plants need to thrive. It plays a key role in chlorophyll production and photosynthesis. It also helps disintegrate enzymes and ensures nitrates are available for plant growth.
While a deficiency of this mineral is rare, it can be caused by high pH levels or excessive iron in the soil. When this happens, manganese becomes unavailable to plants.
Symptoms of manganese deficiency in marijuana plants include yellowing and discoloration of leaves. Generally, they appear as brown or grayish spots that start to form on the tips and margins of the leaves. Eventually, these spots will spread to older leaves and destroy them.
Molybdenum
When growing cannabis, it’s important to pay attention to nutrient deficiencies. They can quickly wreak havoc on your crops and affect their overall quality.
Molybdenum (Mo) is a micronutrient that your cannabis plants need in trace amounts. They use it to assist with nitrate reduction and assimilation, nitrogen metabolism, chlorophyll production, and oxygen reduction.
If your weed plants are suffering from a molybdenum deficiency, they’ll develop yellow, brittle, and dying foliage. It’ll be evident in older leaves in the base of the plant, and it’ll also show up on younger leaves that are closer to the centre of the canopy.
If you suspect a molybdenum deficiency, it’s crucial to flush your weed soil and adjust the pH levels. This will force your marijuana plants to utilize any nutrient reserves they have left, which will help them recover from the deficiency.
