A soil cannabis nutrient schedule starts with plain water for the first two weeks, shifts to a nitrogen-forward feed every other watering during vegetative growth, and moves to a phosphorus and potassium blend once flowering begins. Soil holds nutrients and buffers pH, so most growers feed at half the label rate at first and raise the dose only if the plants ask for more. Keep the root zone between pH 6.0 and 7.0 and water to slight runoff every few feeds to limit salt buildup.
best cannabis nutrient line schedule
What does a week-by-week soil feeding schedule look like?
Timelines shift with cultivar, pot size, and light intensity, but this outline fits most photoperiod and autoflower grows in potting soil.
- Weeks 1 to 2: plain water, no nutrients. Seedlings live on seed reserves and the soil charge.
- Weeks 3 to 4: quarter to half strength grow formula at every other watering.
- Weeks 5 to 8: half to full strength grow formula, plus calcium and magnesium if leaves show spotting.
- Flower weeks 1 to 2: transition feed, roughly a 50/50 blend of grow and bloom.
- Flower weeks 3 to 6: full strength bloom formula at every other watering.
- Flower weeks 7 to finish: taper to plain water for the last 7 to 14 days.
How much should you feed cannabis in soil?
Start at half the manufacturer's label strength and feed at every second or third watering. Watch the leaf tips: a light burn means the dose is high, while pale lower leaves point to a shortage.
When to Start a Cannabis Nutrients Schedule
Pre-charged soils, including many hot organic blends, can carry a plant for 3 to 5 weeks with no added nutrients. Read the bag before you pour.
best cannabis nutrient line schedule
What pH and runoff should soil growers target?
Soil grows do best between pH 6.0 and 7.0, with 6.3 to 6.8 covering most nutrient uptake. Check runoff pH and EC every few weeks; rising EC means salts are collecting and the pot needs a flush.
Do organic soil grows need a different schedule?
Organic soil feeds the microbes rather than the roots, so dry amendments go in every 2 to 3 weeks and compost teas supplement in between. Nutrient release depends on soil temperature and microbial activity, which makes the schedule slower and softer than bottled salt feeds. Organic grows need a heavy flush far less often because unused nutrients stay bound in the soil.
What are the signs of overfeeding or underfeeding?
Overfeeding shows as burnt leaf tips, dark clawing leaves, and a white salt crust on the surface of the soil. Underfeeding shows as pale yellow lower leaves, stalled growth, and thin stems.
Correct overfeeding with plain water and a runoff flush, then resume at a lower dose. Correct underfeeding with a modest bump in strength rather than a sudden jump.
When should you stop feeding before harvest?
Stop nutrient feeds 7 to 14 days before harvest and give plain water. This lets the plant draw on stored reserves and lowers residual salts in the dried flower.