What pH Should Cannabis Soil Be? Target 6.0 to 7.0
Cannabis soil works at pH 6.0 to 7.0. Target 6.5. Below 6.0 and above 7.0, nutrient uptake drops and leaves show it.
Most cannabis pH Up and pH Down concentrates need roughly 1–3 mL per gallon (about 0.25–0.75 mL per liter) to shift a nutrient solution by half a pH point, and the only dose that counts is the one your meter confirms. Mix nutrients first, measure, add the adjuster a few drops at a time, stir, and re-check before adding more. Hitting the target range — about 5.5–6.5 in hydro and coco, 6.0–7.0 in soil — is what keeps calcium, magnesium, and phosphorus available instead of locked out.
Key Features
- Paired pH Up and pH Down bottles for two-way control of reservoir pH
- Highly concentrated formulas, so a small volume treats several gallons
- Works in hydroponic reservoirs, coco coir, peat mixes, and soil drenches
- Mineral pH Down (phosphoric acid) plus citric-acid options for organic runs
- Buffered blends that resist pH drift in soft, low-alkalinity water
- Graduated dropper or measuring cap for repeatable, drop-level dosing
- Reads cleanly on digital pH pens, drop kits, and continuous monitors
pH Up is typically potassium hydroxide or potassium carbonate, while pH Down is phosphoric acid or citric acid, both diluted to a working strength. Expect a pH around 1–2 for concentrated acid blends, which is why gloves and eye protection matter and why you always add adjuster to water rather than water to adjuster. Store bottles upright and tightly capped between 60–80°F, away from direct sun, and never mix Up and Down in the same container — they neutralize each other and can heat up.
Cannabis pH Problems and Yellow Leaves: Diagnosis and Fix Guide
Orders ship discreetly in plain packaging with sealed, leak-checked bottles, and cold weather triggers insulated packing so acids don't separate in transit. Unopened bottles can be returned within the standard window; keep the seal intact and check the label before storing for long periods.
How much pH Up or pH Down should I add per gallon?
Start with 1 mL per gallon, stir for 30 seconds, and re-measure. Most setups need 1–3 mL per gallon to move half a point, and soft water often needs far less than hard water.
how to adjust ph in cannabis water
Do I adjust pH before or after mixing nutrients?
Always after. Nutrients and supplements shift pH on their own, so adjusting first means adjusting twice — dose the full nutrient line, then correct pH as the last step before feeding.
Can I use pH adjusters in living soil?
Yes, but gently. Living soils buffer well, so use citric-acid pH Down in small amounts and check runoff rather than chasing an exact number in the input water.