Leafy herbs hydroponic nutrients: ppm, EC & pH by stage
Leafy herbs wants roughly 140 ppm nitrogen and an EC around 1.4–1.8 mS/cm in veg — here's the full per-stage target table (N, P, K, calcium, magnesium, EC and pH) you dose your reservoir to.
Leafy herbs nutrient schedule (ppm, EC, pH by stage)
| Stage | N | P | K | Ca | Mg | S | Fe | EC | pH |
|---|---|---|---|---|---|---|---|---|---|
| Vegetative | 140 | 40 | 170 | 140 | 40 | 60 | 3 | 1.4–1.8 | 5.5–6.0 |
ppm by element; EC in mS/cm. – = general line rate.
Hitting these numbers
Dose any complete hydroponic fertilizer to the EC above, then check that your N and calcium land near these ppm — leafy herbs is most sensitive to those. Adjust pH into the listed band after mixing, since nutrient uptake falls off outside it. Reservoir EC creeps up as plants drink water faster than nutrients; top up with plain pH-adjusted water and re-check.
FAQ
What EC and ppm does hydroponic leafy herbs need?
In vegetative growth, leafy herbs targets about 140 ppm nitrogen at an EC of 1.4–1.8 mS/cm, with the full N/P/K/Ca/Mg spread and pH shown in the table. Seedlings run lighter; fruiting stages (where relevant) shift toward more potassium.
What pH for hydroponic leafy herbs?
Keep the reservoir in the pH band listed per stage (typically 5.5–6.2 for leafy herbs); outside it, iron and phosphorus uptake drop off even when the ppm are correct.
Can I use one nutrient mix for leafy herbs all the way through?
You can, but you'll get better results shifting the ratio and EC by stage as the table shows — lighter and lower-EC for seedlings, fuller in veg, and more potassium if it fruits.
Nutrients to hit these numbers
Any complete hydroponic line hits these targets — you just dose to the EC and adjust for your crop stage.
- A 3-part line like General Hydroponics Flora trio lets you shift the N-P-K ratio between veg and fruiting.
- MasterBlend 4-18-38 + calcium nitrate + Epsom salt is the cheap DIY route that hits the same ppm.
- You can't dose by eye — a calibrated EC/ppm + pH meter is what turns these targets into a real reservoir.
Some links above are affiliate links — if you buy through them, Moon Dog may earn a small commission at no extra cost to you. We only point to gear we'd actually use.
Sources
Targets are typical published values; your water's starting EC and alkalinity shift the final dose. Targets per Penn State Extension — modified Sonneveld leafy-herb recipe.