Plants need 17 essential nutrients to grow. In hydroponics, you control every one of them. Understanding how they work, how they interact, and what goes wrong is the foundation of expert growing.

πŸ’ͺ Macronutrients (High Demand)

N β€” Nitrogen
Drives leaf and stem growth Β· Deficiency: yellowing lower leaves Β· Toxicity: dark green, delayed fruiting
P β€” Phosphorus
Root development and flowering Β· Deficiency: purple stems Β· Most available at pH 6.0–7.0
K β€” Potassium
Fruit quality and disease resistance Β· Deficiency: brown leaf edges Β· Critical in fruiting stage

πŸ”¬ Secondary Macronutrients

Ca β€” Calcium
Cell wall strength Β· Tip burn in lettuce Β· Must have adequate airflow and circulation
Mg β€” Magnesium
Core of chlorophyll molecule Β· Deficiency: interveinal chlorosis on older leaves
S β€” Sulfur
Enzyme function and protein synthesis Β· Deficiency: yellowing new leaves

βš—οΈ Key Micronutrients

Fe β€” Iron
Most commonly deficient micronutrient Β· Interveinal chlorosis on new leaves Β· Locked out above pH 7.0
Mn β€” Manganese
Enzyme activation Β· Deficiency similar to iron but on younger leaves
Zn, Cu, B, Mo, Cl, Ni
Trace elements β€” supplied by complete A+B nutrient solutions in correct ratios

πŸ“Š EC & Nutrient Reference Table

CropEC Range (mS/cm)pH RangeNotes
Lettuce1.2 – 2.06.0 – 7.0Reduce EC in high heat
Tomato2.0 – 4.05.5 – 6.5Increase EC in fruiting stage
Basil1.0 – 1.65.5 – 6.5Low EC for best flavour
Strawberry1.0 – 1.45.5 – 6.5Very sensitive to high EC
Cucumber1.7 – 2.55.5 – 6.0Consistent EC critical
Pepper/Chilli2.0 – 3.55.5 – 6.5Higher EC improves flavour intensity
Spinach1.8 – 2.36.0 – 7.0Sensitive to tip burn
Mint2.0 – 3.05.5 – 6.5Vigorous feeder

Source: General hydroponic agronomic data. Always verify with your specific nutrient manufacturer’s recommendations. EC and pH targets may vary by growth stage.


⚑ EC / pH Calculator πŸ” Diagnose Deficiency