Grow More publishes its water-soluble powders as a numbered catalog, not as a feeding program, so matching an analysis to a growth stage falls to the grower. Four products carry a pepper crop from tray to ripe pod: 20-20-20 for seedlings, 30-10-10 for early vegetative growth, 10-52-10 into flower initiation, and 6-30-30 or the hydroponic 10-11-40 Pepper-Herb blend for fruit fill. This page works through the whole catalog, the mixing arithmetic and the tank chemistry. For the short version, read the Grow More quick guide.
The catalog as Grow More actually lists it
Two figures circulate on pepper forums that do not appear in the company's catalog. Grow More sells 10-52-10, not 10-55-10, and 5-10-30, not 5-10-40. The seaweed products carry the Sea Grow name and their own analyses. The micronutrient line runs on chelates and nitrates rather than on sulfate salts, so a grower reaching for magnesium sulfate is reaching outside the brand.
| Product | Stage it suits | Nutrient emphasis | Notes. |
| 20-20-20 | Seedling and transplant | Balanced | The default starter analysis in the powder line. |
| 15-15-15 | Seedling and transplant | Balanced, lower salt load | A gentler balanced option than 20-20-20. |
| 21-7-7 | Early vegetative | Acid-forming nitrogen | Suits alkaline irrigation water. |
| 30-10-10 | Early vegetative | High nitrogen | Pushes leaf area. Stop it at first bud. |
| 10-52-10 | Pre-bloom and flower initiation | High phosphorus | The correct code. 10-55-10 does not exist here. |
| 0-50-30 | Flowering and early fruit set | Phosphorus and potassium, no nitrogen | Strong. Alternate it with a nitrogen source. |
| 6-30-30 | Bloom support and early fruit | High phosphorus and potassium | Carries a little nitrogen, so it sustains the canopy. |
| 5-10-30 | Fruit fill and ripening | High potassium | The correct code. 5-10-40 does not exist here. |
| 10-11-40 Pepper-Herb | Fruit fill, hydroponics | Very high potassium | The one formula Grow More names for peppers. |
| Sea Grow 16-16-16 | All stages | Kelp extract with balanced N-P-K | Sold as All Purpose, not as a plain extract. |
| Sea Grow 4-26-26 | Flowering | Kelp extract with P and K | Sold as Flower and Bloom. |
| FOLIAR CAL | Fruit set | Calcium nitrate solution | Never in the same tank as a phosphate. |
| 13% Iron EDTA | As needed | Iron | Holds iron to about pH 6.5. |
| 6% Iron EDDHA | As needed | Iron | The chelate that survives alkaline water. |
| 6% Magnesium EDTA, MAG-NITE | As needed | Magnesium | The brand's magnesium, in place of Epsom salt. |
What the plant takes up, and when
A pepper plant runs on nitrogen while it builds leaf area, then shifts demand toward potassium and calcium as pods size up. New Mexico State University Extension puts the field version plainly: work from a soil test, place phosphorus before planting, and sidedress nitrogen about a week after flowering starts. NMSU also warns against overstimulating with nitrogen, which buys canopy at the cost of fruit. The same logic drives the switch from 30-10-10 to 10-52-10 and then to 5-10-30.
Mixing arithmetic that does not depend on a teaspoon
Teaspoon doses vary with how finely a powder is milled, so weigh instead. One gram of 20-20-20 dissolved in one liter delivers 200 ppm nitrogen, because 20 percent of one gram is 200 milligrams. Halve the weight for 100 ppm. UMass Extension puts constant feed for greenhouse crops at 150 to 250 ppm nitrogen, a floriculture figure rather than a pepper-specific one, so treat it as a ceiling to work down from. Dissolve powders completely in warm water before they reach the reservoir, and dilute foliar sprays to a quarter or half of soil strength.
Which products must never share a tank?
Calcium and phosphate form insoluble calcium phosphate, which drops out of solution and plugs emitters. Clemson Extension and the e-GRO group both put calcium nitrate on the list of fertilizers that need their own stock tank, away from phosphates and from sulfates. FOLIAR CAL therefore goes in tank A, and 10-52-10, 0-50-30 and 6-30-30 go in tank B. Magnesium belongs with the calcium side. Before any new combination goes into a working reservoir, run a jar test: mix at full stock concentration in a jar and watch it for 12 to 24 hours. Cloudiness, crystals or heat mean the mix has failed.
pH and salt, the two numbers that quietly cost yield
Hold a nutrient solution near 5.8 to 6.5, because iron and manganese availability falls off above that band. Soil is a different animal. NMSU Extension reports that chile peppers in New Mexico grow well in loam and sandy loam at pH 7.0 to 8.5, so the narrow band belongs to the reservoir, not to the ground. Growers on alkaline water should reach for 6% Iron EDDHA rather than the EDTA chelate, which loses its grip as pH climbs. Salt accumulation in containers shows up as a rising runoff EC before it shows up in the leaves, so flush with plain water every three to four weeks and read the runoff. More detail sits in nutrient lockout in peppers and dosing and diluting fertilizer.
How should feeding change by growing style?
Containers hold little buffer, so feed weaker and more often, and flush on a schedule. Greenhouse crops justify an EC meter and batch mixing, with powders pre-dissolved before they hit the reservoir. Field beds need water after feeding to move salts past the crown and off the foliage. Irrigation water chemistry matters more than most growers expect: hard water above pH 7.5 precipitates phosphate on its own, which is one reason the 21-7-7 acid-forming analysis exists. Send a water sample out once, then stop guessing. Soil testing answers the other half.
Does the analysis matter more than the brand?
No. A 5-10-30 from any reputable manufacturer feeds a ripening pod the same way, and the label ratio is what the roots respond to. What Grow More offers is a coherent set of analyses with EDTA-chelated micronutrients already in the powder, which removes one mixing step. Match the numbers, then buy on price and availability. Growers comparing brands can work from the fertilizer chart and the general fertilizer guide.
Species and variety notes
Feeding rates scale with plant size rather than with heat. A Rocoto, a large Capsicum pubescens that runs for years, takes far more total nutrition across a season than a Shishito in a five-gallon pot. Long-season C. chinense types such as Habanero hold fruit and foliage at the same time, so they tolerate a nitrogen floor through fruit fill that a determinate-looking Jalapeño does not need. Cut the rate, not the frequency, when a plant sulks.
Sources & Further Reading
- Grow More, Inc. Fertilizers and Micronutrients product listings.
- Walker, S., and P.W. Bosland. Growing Chile Peppers in New Mexico Gardens. New Mexico State University Extension, Guide H-240.
- Clemson University. Selecting Fertilizer Mixtures for Fertigation. Land-Grant Press.
- e-GRO. Three Methods to Check Fertilizer Compatibility.
- UMass Extension. Basic Fertilizer Programs for Containerized Greenhouse Crops.
- Priest, C.T., and D.J. Austin. The Chile Pepper Almanac. Harambe Publishing, 2026. Amazon
- WikiPepper. Micronutrients for Pepper Plant Growth.