Nutrient deficiency is the issue.
Without much more info it can be hard to help. Age of plant? Photo or auto? Nutrient type?
Since you’re new to this, I’ll help to explain what I see:
1 Yellowing Leaves (Chlorosis):
2 Widespread yellowing, starting from the leaf edges and tips, indicates a nutrient deficiency, likely nitrogen or magnesium.-The older leaves are more affected, suggesting a mobile nutrient deficiency (these nutrients can move from older leaves to new growth).
3 Brown Leaf Tips and Edges (Necrosis/Burnt Tips):-This often points to nutrient burn or an excess of salts in the root zone (common in hydroponics if EC/PPM is too high).
4 Leaf Curling and Damage:-Some leaf edges are curling down or showing twisted growth. This can indicate pH imbalances or environmental stress (e.g., heat stress, low humidity)
.Possible Causes:
-pH Imbalance: If the pH of the nutrient solution is outside the ideal range (5.5–6.2 for hydro), nutrient uptake is impaired.
-Nutrient Deficiency: Insufficient nitrogen, magnesium, or iron could cause chlorosis and necrosis.
-Nutrient Toxicity: Overfeeding or nutrient salt buildup can burn leaf edges. (Probably not this because your EC is too low for a plant this far into veg)*
-Root Health: Poor root aeration or root rot can cause similar leaf symptoms.
*Just as a side-note….With an EC this low, the chlorosis and necrosis symptoms are likely due to nutrient deficiencies rather than toxicity. Even though 0.7–0.8 EC is typically suitable for very young seedlings, this plant looks a bit further along and would need higher nutrient strength.
What’s Happening:
-Nitrogen deficiency: Lower leaves turning yellow (mobile nutrient).
-Magnesium deficiency: Interveinal chlorosis seen in older leaves (also a mobile nutrient).
-Possible Potassium deficiency: The burnt edges on older leaves can be a sign of K deficiency as well​
Recommendations:
Check pH: Ensure the nutrient solution is between 5.5–6.2.
Check EC/PPM: For young plants or stressed plants, keep EC around 0.8–1.2 mS/cm (400–600 PPM).
Flush and Reset: If there’s a salt buildup, flush the system with pH-balanced water and reintroduce a balanced nutrient solution.
Check Environmental Conditions: Ensure proper light intensity, temperature (22–28°C), and RH (50–65%).
Inspect Roots: Check for healthy white roots. If roots are brown or slimy, root rot may be present.
Recommendations for Correction:
Increase EC gradually: Raise to around 1.0–1.2 mS/cm (500–600 PPM) to provide a more complete nutrient profile.
Use a balanced veg nutrient: Ensure the solution includes Mg, Ca, and micronutrients.
Keep an eye on new growth: If new leaves come out green and healthy after adjusting EC, you’ve corrected the deficiency.
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