This is under the FAQ at blackdog led, which so happens where I bought my light.. so I been hearing alot of people saying leds can cause a cal/mag deficiency so I'll paste this here and see what ya'll think.. correct me if I'm wrong I just don't see how light could give a difficiency , (soil obviously yes if your soil is low in nutrients) unless there is a proven scientific fact ya'll can let me know about. Knowledge is key..
No, LED lights do not cause any kind of nutrient deficiency.
A rumor was started that LED lights cause magnesium deficiency when people noticed that some plants develop purple petioles (leaf stalks) or streaks on the stems under LED lights, but not under HPS lights. While purple coloration on stems and petioles can be one of the signs of magnesium deficiency, it is also a sign that the plant is producing natural purple pigments (anthocyanin) in response to ultraviolet (UV) light. Many artificial lights (including HPS and most LEDs) don't give off UV light, so plants grown under these lights don't produce this natural pigmentation. Under these UV-lacking lights, purple coloration is often a sign of magnesium deficiency. However, when grown under UV-containing Black Dog LED lights or natural sunlight, plants will produce their full range of natural pigmentation-- it is not necessarily a sign of a nutrient deficiency.
The major symptom of magnesium deficiency is usually yellowing, blotchy-looking (chlorotic) leaves, accompanied by purple stems and petioles. When growing under Black Dog LED grow lights, unless the leaves are chlorotic, purple stems and petioles are not a sign of a magnesium deficiency-- they are a sign of a happy, healthy plant.
No, LED lights do not cause any kind of nutrient deficiency.
A rumor was started that LED lights cause magnesium deficiency when people noticed that some plants develop purple petioles (leaf stalks) or streaks on the stems under LED lights, but not under HPS lights. While purple coloration on stems and petioles can be one of the signs of magnesium deficiency, it is also a sign that the plant is producing natural purple pigments (anthocyanin) in response to ultraviolet (UV) light. Many artificial lights (including HPS and most LEDs) don't give off UV light, so plants grown under these lights don't produce this natural pigmentation. Under these UV-lacking lights, purple coloration is often a sign of magnesium deficiency. However, when grown under UV-containing Black Dog LED lights or natural sunlight, plants will produce their full range of natural pigmentation-- it is not necessarily a sign of a nutrient deficiency.
The major symptom of magnesium deficiency is usually yellowing, blotchy-looking (chlorotic) leaves, accompanied by purple stems and petioles. When growing under Black Dog LED grow lights, unless the leaves are chlorotic, purple stems and petioles are not a sign of a magnesium deficiency-- they are a sign of a happy, healthy plant.
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