Beginner Nutrient Schedule: EC/pH Targets by Stage

New growers usually mix nutrients by “feel” and then fight pH swings, weak growth, burnt roots or deficiencies. Instead, use this simple stage-by-stage guide. You’ll know exactly what EC and pH to target for each phase of growth, no matter what brand of nutrients you use.

Step 1 Understand EC and pH

EC tells you how strong your nutrient mix is. pH controls how well roots absorb those nutrients. Nail both and 90% of beginners’ problems disappear.

• EC low: pale, slow growth.
• EC high: leaf burn, droop, tip burn.
• pH outside range: nutrients present, but locked out.

Here are the safe beginner ranges before jumping into the schedule:

Step 2 Set EC & pH by growth stage

Use this simple schedule for NFT, DWC, coco/perlite, Kratky or any recirculating hydroponic system.

Germination (days 1–7)

Typical duration: about 3–7 days until the first true leaves appear.

• EC: 0.2–0.4
• pH: 5.5–5.8
• Why: Seeds don’t need nutrients; avoid burning the taproot.

Early Seedling (week 2)

Typical duration: about 7–14 days after germination while roots are establishing.

• EC: 0.5–0.8
• pH: 5.6–6.0
• Why: Roots begin absorbing nitrogen; still very sensitive to salts.

Vegetative Growth

Typical duration: 2–4 weeks for leafy greens and herbs; 3–6 weeks for taller fruiting crops.

• Leafy greens EC: 1.0–1.4
• Herbs EC: 1.2–1.6
• Taller fruiting crops EC: 1.6–2.2
• pH: 5.7–6.1

Transition to Flower / Pre-fruit

Typical duration: 7–14 days while plants shift from vegetative growth into flowering.

• EC: +0.2–0.4 above your vegetative target.
• pH: 5.8–6.2

This is where most beginners underfeed fruiting crops.

Flowering / Fruiting

Typical duration: 4–8+ weeks depending on crop and variety.

• Tomato/pepper EC: 2.0–3.0
• Cucumber EC: 1.8–2.4
• Strawberries EC: 1.4–1.8
• pH: 5.8–6.3

Step 3 Adjust EC safely

Never jump EC up or down by more than 0.3–0.4 at once. Sudden changes shock roots.

• EC too high? Add plain water to the reservoir, mix and re-test.
• EC too low? Add nutrient stock a little at a time, mix thoroughly, then re-check.
• EC rising daily? Plants are drinking water faster than nutrients → top up with plain water.
• EC dropping daily? Plants are hungry → increase nutrient strength slightly.

Step 4 Keep pH in the safe zone

pH is stable only when the nutrient balance and root environment are stable.

• Always measure pH after mixing nutrients.
• Aim for slow, small adjustments with pH down or pH up.
• Let pH float naturally between 5.6–6.3 rather than “chasing” a perfect number.

Step 5 Beginner mistakes to avoid

• Mixing nutrients in the wrong order (follow A → B → additives → pH).
• Letting pH drift above 6.5 for too long → micronutrient lockout.
• Running vegetative EC on fruiting crops → weak yield, blossom drop.
• Treating “deficiencies” before checking EC and pH.