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🌿 Unlock your garden’s secret weapon for lush growth & vibrant blooms!
Humboldts Secret CalMag & Iron is a premium liquid fertilizer delivering calcium, magnesium, and chelated iron in a fast-absorbing formula. Designed for hydroponic, soil, coco, and RO water systems, it prevents nutrient deficiencies, strengthens stems, enhances leaf color, and supports vigorous vegetative and flowering growth. Ideal for both indoor and outdoor gardens, this 1-gallon concentrate ensures maximum nutrient uptake and helps prevent common issues like blossom end rot, making it a must-have for professional and hobbyist growers alike.
| ASIN | B01GB23TD0 |
| Best Sellers Rank | #14,341 in Patio, Lawn & Garden ( See Top 100 in Patio, Lawn & Garden ) #531 in Garden Fertilizers |
| Brand Name | Humboldts Secret |
| Coverage | Medium |
| Customer Reviews | 4.6 4.6 out of 5 stars (2,037) |
| Global Trade Identification Number | 00648260730406 |
| Item Form | Liquid |
| Liquid Volume | 128 Fluid Ounces |
| Manufacturer | Humboldts Secret |
| Mixing Ratio | 2-5 ml/gallon |
| Model Number | CalMag & Iron |
| Specific Uses For Product | Hydroponic |
| Target Species | flowering plants |
| UPC | 648260730406 |
| Unit Count | 128 Fluid Ounces |
J**7
This stuff WORKS!!
This stuff is great! My pepper plants were turning yellow and had blossom end rot so they were getting a lottlw rotten hole before they were even ready to pick. I read online that several ppl recommended this for that problem. It was like a miracle, I used it twice and my plants turned green again and the peppers started growing perfectly! I kept using them as recommended and got so many beautiful peppers from my plant all summer! Life saver! Plus it is so concentrated, you only use about a cap full with a gallon of water so it will last FOREVER!
T**N
Humboldts
Very nice quantity & quality
E**E
Works well
My tomatoes are doing much better. No ugly black spots on the bottom.
S**E
Great product as always
Great product works well
K**O
Quickly shows improvement to my house plants. Good company
Had some confusing instructions but their customer service got back to me quickly and cleared confusion. The jug arrived with no leak, has no order and my house plants are happy to get the dose of this fertilizer, especially my old lemon tree which goes out in summer and come in for winter. I notice when plants are healthy not many bugs appear. as it takes very little per gallon of water, it's a good value for the price.
L**�
As advertised
Perfect!
S**N
I must need product
Great product works wonderful and to be honest it kinda looks like it works miracles. But I recommend everyone to at least try. You have a one shot and I guarantee you won’t be let down happy growing
A**R
Works as intended
Works like a charm
Trustpilot
1 month ago
3 weeks ago