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Any first-year gardener can tell you that plants can be a mystery. Learning to grow healthy cannabis plants from seed to flower is no exception. To be a successful grower, you must know about pests, soil, light, and hydration levels. But one of the hardest things to overcome initially is nutrient deficiencies. This article will discuss a few nutrient deficiencies and how to conquer them.

Calcium (chemical symbol “Ca”) Deficiency

Calcium deficiency is a common problem in cannabis plants; you’ll notice plants with a calcium deficiency often have malformed leaf tips or parachute-shaped leaves; they will usually be yellow at the edges or show dark brown spots. Calcium is an essential component of cell walls and cell membranes, so this affects the plant’s root tips and leaves. A Calcium deficiency can therefore result in warped structure/lack of structure to new growth. Calcium also helps the flow of Nitrogen and sugars through the plant.

With calcium, typically, it’s an environmental issue; ensuring your grow space has airflow, the soil is warm enough, and your plants are getting the correct amount of water can help with their calcium absorption. If you’ve adjusted all these things and your plants are still deficient, you can try adding calcium products to the soil, such as a bone meal.

Iron (chemical symbol “Fe”) Deficiency

Iron is a semi-mobile macronutrient. It is necessary for the use of nitrates (Nitrogen containing) and sulfates (Sulphur containing) compounds. Iron is also required to produce chlorophyll. Iron deficiencies can occur if pH is out of range. It can also be caused by excess Manganese or Copper. All of these can interfere with Iron uptake. Iron is an important mineral for processes involved in general metabolic and energy-forming processes.

Symptoms of Iron deficiency can initially appear in new plant growth. Interveinal chlorosis can appear at the base of new leaves. After this, the same symptoms can be seen through the leaves and older growth. Overall, yellowing between the leaf veins is a good indicator of Iron deficiency.

Nitrogen (chemical symbol “N”) Deficiency

Nitrogen is essential for healthy cannabis plants; cannabis plants with nitrogen deficiencies often have large leaves that turn pale and even white, they can acquire purple stripes on the stems, and vegetation bursts into forced flowering. Often leaves will curl and shed and yield volumes decrease considerably. Fixing a Nitrogen deficiency is pretty simple; you can begin by working organic matter into your soil, such as bone meal, compost, animal manure, or fish meal.

Copper (chemical symbol “Cu”) Deficiency

Copper helps the plant utilize Nitrogen in addition to assisting in the metabolism of carbohydrates. It’s unusual to see genuine cases of copper deficiency, most grow mediums and feeds have sufficient Copper for the plant requirements. Growers often miss Copper deficiency. It’s commonly recognized when leaves turn dark blue or have especially purple undertones. The tips and edges of the leaves turn bright or white, and sometimes leaves even seem to have a metallic sheen. A problematic symptom is buds that do not ripen. Copper deficiency is most common in the leaves closest to the light source. Some stains will be affected most in the flowering stage and can be identified by leaves showcasing a purple or reddish hue. Growers can correct the copper deficiency by adjusting the soil pH to the correct range, hydrating plants with tap water, and avoiding overwatering.

Magnesium (chemical symbol “Mg”) Deficiency

Magnesium is essential for photosynthesis and is used to make the vital chlorophyll pigment. Without Magnesium, chlorophyll and photosynthesis simply can’t happen. When plants are dealing with a magnesium deficiency, you might notice that the leaf tips or edges die; they will look burnt or turn brown. When your plant is deficient in magnesium, the symptoms often start in the lower leaves and work their way up to the middle and upper parts of the plant. You can use garden lime or worm castings to treat magnesium deficiency, although some growers prefer to use magnesium sulfate directly. If left untreated, the plant shoots will turn white instead of the usual pale green, and the stems will turn purple.

Boron (chemical symbol “B”) Deficiency

Boron is used with Calcium to ensure healthy cell walls and effective cell division. Boron is an immobile macronutrient. It is required in small amounts, so it is one of the less common cannabis nutrient deficiencies to see. Most good quality soils/compost contain sufficient Boron.

A Boron deficiency can manifest in several ways, most commonly with abnormal leaf tips. This can look like thick leaf tips, rough or hollow stems, or yellowing of the leaves. Boron deficiency can be a significant problem as Boron contributes to cell growth, so you’ll see this effect on your plant, most commonly at the roots and shoots.

Plants with Boron deficiency often experience stunting, distortion, and brittle foliage. If you find your plant deficient in Boron, it’s best to start by examining the soil. Using high-quality soil that includes Boron is a great place to start. Other treatments involve adjusting the soil’s pH, stopping reverse osmosis water use, or using a humidifier in the grow room.

Working With a Quality Lab

Getting your plants tested at a reputable lab can inform you about possible nutrient deficiencies in your plants and help you make informed decisions about your growing process. LUX Leaf is an agile lab that has invested heavily in equipment, software, processes, and a nationwide courier network to enable our personnel to deliver results quickly for our clients. Our Goal is to have every lab test that matters to you while providing the highest quality results, because speed is just a number without quality. With LUX, you can expect your results to return quickly and accurately.

We want to be your partner and not just your lab. Your success is our success, so let’s grow your business together.

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