The top pick for a cannabis nutrient feeding chart in soil is a three-part base nutrient schedule with a separate cal-mag supplement, split into seedling, vegetative, transition, early flower, and late flower weeks. I compare charts on five criteria: stage timing, soil pH range, EC or PPM progression, calcium and magnesium coverage, and whether bloom boosters stay separate from base feeds.
How to Prevent Nutrient Burn During Feeding
No chart fits every cultivar, water source, or bagged soil. Use the numbers as a starting range, then adjust with runoff EC, leaf color, and growth rate.
What Nutrients Do Cannabis Plants Need at Each Stage?
Top pick: stage-based three-part chart with cal-mag
A stage-based chart gives you different nitrogen, phosphorus, and potassium ratios as the plant moves from transplant to flip to mid-flower. The best version lists milliliters per gallon, target EC, and pH for each week, plus a cal-mag line that does not disappear in flower.
- Pros: clear stage changes; easy to track EC; separate cal-mag prevents common magnesium shortfalls in soil; works with hand watering.
- Cons: more bottles; cost rises with bloom boosters; requires a decent EC meter; charts can drift from your water profile.
Use case: pick this if you run a small soil garden, water by hand, and want a repeatable record of what changed each week. It is the safest default for photoperiod plants in a peat or coco-based soil mix.
What the chart should cover
A useful soil chart has more than a feeding table. It should show base feed, cal-mag, and any booster as separate columns. It should state the soil pH window, usually 6.0 to 7.0 with 6.2 to 6.8 as a working target for most mixes, and give EC targets by stage. It should also say when to water with plain water or reduce feed, and how to check runoff EC without treating it as a hard rule.
In soil, feed charts often fail because soil holds nutrients and water differently from coco. A chart built for drain-to-waste hydro can overfeed a peat mix. Look for a chart that names soil or peat as the medium.
Option 2: organic dry amendments and top-dress
Organic dry amendments rely on microbes to break down meals and minerals. The feeding chart is a top-dress schedule, not a weekly bottle dose. A common pattern is a base mix at potting, a vegetative top-dress, and a flower top-dress, with compost or worm castings as a carrier.
- Pros: fewer liquid feeds; forgiving if you miss a week; supports living soil; no EC meter needed for the base feed.
- Cons: slower to correct a deficiency; hard to measure exact NPK; needs a larger pot volume; microbial activity depends on moisture and temperature.
Use case: choose this if you grow in large fabric pots, keep a living soil bed, and prefer a slower schedule. It suits gardeners who top-dress every two to three weeks and water with compost tea or plain water.
Option 3: single-bottle all-in-one soil feed
An all-in-one liquid feed is the simplest chart to follow. You mix one product at a measured rate and water. The trade-off is less control over nitrogen during stretch and less ability to raise calcium without raising everything else.
- Pros: low bottle count; easy for one or two plants; fewer mixing mistakes; good for a first soil run.
- Cons: limited stage control; may need a separate cal-mag in soft water; bloom boosters can unbalance the base; hard to match a custom soil mix.
Use case: use this if you grow a few autoflowers on a patio, want one bottle, and will accept a simpler schedule. It is not the first choice for a long-flowering photoperiod plant in a heavy amended soil.
How to read EC and pH in soil
Feed charts list EC because milliliters alone do not tell you the strength of the mix. Start low in seedling and early veg, raise the dose as the root zone fills, and hold or lower it if runoff EC climbs while leaves show tip burn. Check pH after mixing, not before. For soil, a pH near 6.5 is a practical target, but your soil mix and water alkalinity can shift the number.
Use-case recommendation
For most home soil growers, the three-part base plus cal-mag chart is the top pick because it gives clear stage control and a paper trail. Use organic dry amendments if you want a slower top-dress system in large pots. Use an all-in-one bottle if simplicity matters more than fine control. Whichever chart you pick, keep a log of dose, pH, EC, and plant response, then adjust one variable at a time.