---
product_id: 48892108
title: "Professional Grade Ultra Pure Cal-Mag Fertilizer, (1 Gallon) | Helps Reduce Blossom End Rot, Corrects Deficiencies, Boost Calcium Uptake, Made for Hydro & Soil, Supports Tomatoes & Peppers"
brand: "bloom city"
price: "$189.85"
currency: USD
in_stock: true
category: "Bloom City"
url: https://www.desertcart.us/products/48892108-professional-grade-ultra-pure-cal-mag-fertilizer-1-gallon-helps
store_origin: US
region: United States of America
---

# Optimized Cal-Mag ratio for vigorous growth Versatile for soil & hydroponic systems 128 oz ultra-pure liquid formula Professional Grade Ultra Pure Cal-Mag Fertilizer, (1 Gallon) | Helps Reduce Blossom End Rot, Corrects Deficiencies, Boost Calcium Uptake, Made for Hydro & Soil, Supports Tomatoes & Peppers

**Brand:** bloom city
**Price:** $189.85
**Availability:** ✅ In Stock

## Summary

> 🌿 Elevate your garden game with Bloom City’s Cal-Mag UltraPure!

## Quick Answers

- **What is this?** Professional Grade Ultra Pure Cal-Mag Fertilizer, (1 Gallon) | Helps Reduce Blossom End Rot, Corrects Deficiencies, Boost Calcium Uptake, Made for Hydro & Soil, Supports Tomatoes & Peppers by bloom city
- **How much does it cost?** $189.85 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.us](https://www.desertcart.us/products/48892108-professional-grade-ultra-pure-cal-mag-fertilizer-1-gallon-helps)

## Best For

- bloom city enthusiasts

## Why This Product

- Trusted bloom city brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Pure Power Boost:** Ultra-pure calcium and magnesium for peak plant vitality
- • **Proudly Made in USA:** Quality you can count on, grown with care and precision
- • **Growth You Can Trust:** Supports sturdy stems and lush foliage for professional-grade results
- • **All-in-One Versatility:** Perfectly formulated for indoor, outdoor, and hydroponic setups
- • **Maximized Nutrient Absorption:** Enhances uptake efficiency to supercharge your garden’s health

## Overview

Bloom City Professional Grade Ultra Pure Cal-Mag Fertilizer delivers a potent 128 oz liquid formula designed to supply essential calcium and magnesium for robust plant growth. Ideal for soil and hydroponic systems, it enhances nutrient uptake and supports strong plant structure, making it a top choice for indoor and outdoor gardening enthusiasts seeking professional results.

## Description

desertcart.com : Bloom City Professional Grade Ultra Pure Cal-Mag Growing Fertilizer,Gallon (128 oz) : Patio, Lawn & Garden

## Features

- Calcium & Magnesium Growing Support – Formulated to supply essential nutrients for active plant growth.
- Supports Plant Strength & Development – Helps encourage sturdy structure and steady growth.
- Improves Nutrient Uptake Efficiency – Supports balanced feeding and overall plant performance.
- Ideal for Soil & Hydroponic Systems – Suitable for indoor plants, gardens, and hydroponic growing.
- Made in USA

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B073ZP47ZN |
| Best Sellers Rank | #1,218 in Patio, Lawn & Garden ( See Top 100 in Patio, Lawn & Garden ) #65 in Garden Fertilizers |
| Brand Name | Bloom City |
| Coverage | Full |
| Customer Reviews | 4.6 4.6 out of 5 stars (6,839) |
| Item Form | Liquid |
| Liquid Volume | 1 Gallons |
| Manufacturer | Bloom City |
| Mixing Ratio | 2-4 mL per gallon (vegetative stage), 3-5 mL per gallon (bloom) |
| Model Number | Cal-Mag UltraPure | Plus Micros |
| Number of Items | 1 |
| Part Number | BCALMAG1G |
| Target Species | Houseplants, Greenhouse Plants, Edible Plants (fruits and veggies), Trees, Turf |
| UPC | 841401125158 |
| Unit Count | 128 Ounce |

## Product Details

- **Brand:** Bloom City
- **Item Form:** Liquid
- **Liquid Volume:** 1 Gallons
- **Manufacturer:** Bloom City
- **Number of Packs:** 1

## Images

![Professional Grade Ultra Pure Cal-Mag Fertilizer, (1 Gallon) | Helps Reduce Blossom End Rot, Corrects Deficiencies, Boost Calcium Uptake, Made for Hydro & Soil, Supports Tomatoes & Peppers - Image 1](https://m.media-amazon.com/images/I/61BOCBiCtuL.jpg)

## Available Options

This product comes in different **Size** options.

## Questions & Answers

**Q: Is there nitrogen in this?  It would be helpful for the seller to post the bottle back side label.**
A: Hey there, good idea on posting the labels, adding that to my to-do list!  To answer your question, yes there is Nitrogen.  Here is the guaranteed analysis of nutrient content on our Cal-Mag.  Total Nitrogen 2%, 2% Nitrate Nitrogen, Calcium 2%, Magnesium 0.6%, Boron .002%, Copper .003%, iron .004%, Manganese .004%, Zinc .004%.  Derived from: Calcium Nitrate, Magnesium Nitrate, Boric Acid, Copper Sulfate, Ferric Sulfate, Manganese Sulfate, Zinc Sulfate.

Hope that helps!

James - Bloom City Crew

**Q: Site says it is compatible with all  growth mediums, but bottle says for hydroponic use ONLY. Which is it?**
A: That terminology on the bottle is unfortunately a labeling requirement placed on us by regulators.  It is compatible with all growing mediums, including soil, cocoa coir, peat, hydroponic systems, etc.  

Thanks,
James - Bloom City Crew

**Q: Can this be mixed with epsom salt for additional magnesium as a foliar spray or added as a root drench?**
A: Hi, Great question.  It can be added to epsom salt in a water solution, however we suggest you try this Cal-Mag first on the plants - its probably more than enough magnesium.  We use highly bio-available mineral forms and add organic acids to the product to increase uptake.  Its also great as both a foliar spray and a root drench!  Let us know how the plants grow!

**Q: What would be the salt in ppm per dose added to ro or distilled water?**
A: Hi, thanks for the question!  The PPM added would be about 120 for the low dose of 2ml per gallon, and 240 for the high dose of 4ml per gallon.  Let us know if you have any other questions!

James - Bloom City Crew

## Frequently Bought Together

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*Product available on Desertcart United States of America*
*Store origin: US*
*Last updated: 2026-07-25*