--- product_id: 48892108 title: "Professional Grade Ultra Pure Cal-Mag Growing Fertilizer,Gallon (128 oz)" brand: "bloom city" price: "€ 116.18" currency: EUR in_stock: true reviews_count: 8 category: "Bloom City" url: https://www.desertcart.hr/products/48892108-professional-grade-ultra-pure-cal-mag-growing-fertilizer-gallon-128 store_origin: HR region: Croatia --- # Compatible with soil & hydroponics 128 oz ultra-pure liquid formula Balanced Ca & Mg for nutrient synergy Professional Grade Ultra Pure Cal-Mag Growing Fertilizer,Gallon (128 oz) **Brand:** bloom city **Price:** € 116.18 **Availability:** ✅ In Stock ## Summary > 🌿 Elevate your garden game with Bloom City’s pure Cal-Mag power! ## Quick Answers - **What is this?** Professional Grade Ultra Pure Cal-Mag Growing Fertilizer,Gallon (128 oz) by bloom city - **How much does it cost?** € 116.18 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.hr](https://www.desertcart.hr/products/48892108-professional-grade-ultra-pure-cal-mag-growing-fertilizer-gallon-128) ## 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 - • **Made in the USA:** Crafted with care domestically, ensuring premium quality and reliability. - • **Pure Power Boost:** Ultra-pure Cal-Mag formula fuels vigorous plant growth and resilience. - • **Dual Nutrient Synergy:** Calcium and magnesium work together to strengthen stems and optimize photosynthesis. - • **Effortless Application:** Ready-to-use liquid form mixes easily—no powders, no hassle, just pour and grow. - • **Versatile Growth Partner:** Perfectly formulated for both soil gardens and cutting-edge hydroponic setups. ## Overview Bloom City Professional Grade Ultra Pure Cal-Mag Fertilizer delivers a potent 128 oz liquid formula designed to correct calcium and magnesium deficiencies, supporting robust plant structure and enhanced nutrient uptake. Ideal for both soil and hydroponic systems, this USA-made fertilizer ensures steady, healthy growth for all plant stages with easy, no-fuss application. ## Description Product description Multiple applications for pots, garden beds and foliar spray. Use in watering can for precision nutrition. Mix 2-4 mL per gallon of water during grow phase, mix 3-5 mL per gallon of water during bloom phase. Use with every watering. Use with hose end sprayer for larger areas. Use a mixing ratio of 1:100 or 1:200, apply 1-2 times monthly. Use as a foliar spray for rapid nutrient uptake. Mix with water at 4-8 tsp. per gallon for all stages of growth, apply once weekly. Bloom City Values Bloom City gives the power of clean, regenerative gardening to the home grower with full-spectrum plant nutrition for bountiful yields in any growing environment. Our emphasis on environmentally responsible production methods with natural & sustainable input sourcing makes for more bio-available nutrient outputs & safer, cleaner gardens. Bloom City's nutrient systems are everything you need to grow lush, beautiful gardens without harsh chemical fertilizers. Harness the power of regenerative growing practices to create living soil & vibrant plants. Review: Best plant fertilizer - I’ve been using the Bloom City Professional Grade Ultra Pure Cal-Mag (32 oz) for my plants, and I’m very impressed with the results. It’s made a noticeable difference in overall plant health—especially with preventing calcium and magnesium deficiencies that can show up as yellowing leaves or weak growth. The formula is clean and easy to mix, and a little goes a long way. I’ve used it with both soil and hydro setups, and it works great across the board. My plants look greener, stronger, and more vibrant since adding this to my routine. Another big plus is that it doesn’t cause buildup or clogging in my system, which I’ve had issues with in the past when using other brands. If you’re growing vegetables, houseplants, or anything that needs that extra nutrient boost, this is definitely worth trying. Reliable quality and consistent results. I'll be buying again! Review: Great for correcting nutrient deficiencies - This is the only general micronutrient supplement I ever buy. I first got it when my younger plants started showing signs of nutrient deficiencies outside of NPK nutrients. My plants showed signs of recovery after one watering and a few foliar applications. Some people might not need it, especially if they are growing in properly enriched soil, but I have water that's softened at a municipal level. As a result, some minerals have been removed from my water; this product helps restore those and add others that are good for all plant growth stages, from new plants to blooming plants. Use is simple. Just measure out however much I want to add to my 2-gallon can, dump it in, add water, and water my plants as usual. No worrying about presoaking anything or lots of stirring to mix in powders. (for simplicity, I use a different fertilizer bottle's cap to measure out ~8ml when filling my watering can) The bottle cap/lid and recommended measurements have changed from the previous bottle I bought. The ingredients list is the same, as well as the concentration percentages of the minerals. They also separate the use guidelines/directions differently between them. I'll only mention the amount differences. New: watering can: 1tsp (2.5-5ml)/gallon Hose end sprayer: 1tsp (5ml) approx 1:750 ratio Foliar spray: 2-4tsp (10-20ml)/gallon Old: Grow phase: 2-4ml/gallon Bloom phase: 3-5ml/gallon Sprayer instructions: 20-40ml/gallon Not sure why they changed the amounts, but it's helpful to know the ratio for using with a hose end sprayer. Overall, great value for money in my opinion. ## 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 | #1,347 in Patio, Lawn & Garden ( See Top 100 in Patio, Lawn & Garden ) #68 in Garden Fertilizers | | Brand | Bloom City | | Brand Name | Bloom City | | Coverage | Full | | Customer Reviews | 4.6 out of 5 stars 6,833 Reviews | | Item Form | Liquid | | Item Weight | 128 Ounces | | 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 | | Number of Packs | 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 - **Item Weight:** 128 Ounces - **Liquid Volume:** 1 Gallons - **Number of Packs:** 1 ## Images ![Professional Grade Ultra Pure Cal-Mag Growing Fertilizer,Gallon (128 oz) - Image 1](https://m.media-amazon.com/images/I/61BOCBiCtuL.jpg) ![Professional Grade Ultra Pure Cal-Mag Growing Fertilizer,Gallon (128 oz) - Image 2](https://m.media-amazon.com/images/I/819b51Y6x6L.jpg) ![Professional Grade Ultra Pure Cal-Mag Growing Fertilizer,Gallon (128 oz) - Image 3](https://m.media-amazon.com/images/I/81FASSzoi9L.jpg) ![Professional Grade Ultra Pure Cal-Mag Growing Fertilizer,Gallon (128 oz) - Image 4](https://m.media-amazon.com/images/I/816+CxuUnIL.jpg) ![Professional Grade Ultra Pure Cal-Mag Growing Fertilizer,Gallon (128 oz) - Image 5](https://m.media-amazon.com/images/I/812lYWScaDL.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 ## Customer Reviews ### ⭐⭐⭐⭐⭐ Best plant fertilizer *by J***W on March 26, 2026* I’ve been using the Bloom City Professional Grade Ultra Pure Cal-Mag (32 oz) for my plants, and I’m very impressed with the results. It’s made a noticeable difference in overall plant health—especially with preventing calcium and magnesium deficiencies that can show up as yellowing leaves or weak growth. The formula is clean and easy to mix, and a little goes a long way. I’ve used it with both soil and hydro setups, and it works great across the board. My plants look greener, stronger, and more vibrant since adding this to my routine. Another big plus is that it doesn’t cause buildup or clogging in my system, which I’ve had issues with in the past when using other brands. If you’re growing vegetables, houseplants, or anything that needs that extra nutrient boost, this is definitely worth trying. Reliable quality and consistent results. I'll be buying again! ### ⭐⭐⭐⭐⭐ Great for correcting nutrient deficiencies *by G***E on June 12, 2025* This is the only general micronutrient supplement I ever buy. I first got it when my younger plants started showing signs of nutrient deficiencies outside of NPK nutrients. My plants showed signs of recovery after one watering and a few foliar applications. Some people might not need it, especially if they are growing in properly enriched soil, but I have water that's softened at a municipal level. As a result, some minerals have been removed from my water; this product helps restore those and add others that are good for all plant growth stages, from new plants to blooming plants. Use is simple. Just measure out however much I want to add to my 2-gallon can, dump it in, add water, and water my plants as usual. No worrying about presoaking anything or lots of stirring to mix in powders. (for simplicity, I use a different fertilizer bottle's cap to measure out ~8ml when filling my watering can) The bottle cap/lid and recommended measurements have changed from the previous bottle I bought. The ingredients list is the same, as well as the concentration percentages of the minerals. They also separate the use guidelines/directions differently between them. I'll only mention the amount differences. New: watering can: 1tsp (2.5-5ml)/gallon Hose end sprayer: 1tsp (5ml) approx 1:750 ratio Foliar spray: 2-4tsp (10-20ml)/gallon Old: Grow phase: 2-4ml/gallon Bloom phase: 3-5ml/gallon Sprayer instructions: 20-40ml/gallon Not sure why they changed the amounts, but it's helpful to know the ratio for using with a hose end sprayer. Overall, great value for money in my opinion. ### ⭐⭐⭐⭐⭐ Calcium magnesium fertilizer *by M***Y on September 18, 2025* I grow bell peppers and other types of peppers in my garden. Sometimes they need calcium and magnesium to fertilize them or they start getting the source fights on them. I decided to try this one to see if it would work. I use this and within a week, my plants perked up really well. The pepper started looking very nice and green and healthy. I’m very satisfied with this product. I would suggest this for anybody this fertilizer is good quality it’s effective and being organic makes it even better. ## Frequently Bought Together - Bloom City Professional Grade Ultra Pure Cal-Mag Growing Fertilizer,Gallon (128 oz) - Bloom City Organic Liquid Seaweed and Kelp Fertilizer Supplement (128 oz) Concentrated Makes 750 Gallons - Bloom City Liquid Silica Boost Fertilizer and Supplement, Gallon (128 oz) Concentrated Makes 750 Gallons --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.hr/products/48892108-professional-grade-ultra-pure-cal-mag-growing-fertilizer-gallon-128](https://www.desertcart.hr/products/48892108-professional-grade-ultra-pure-cal-mag-growing-fertilizer-gallon-128) --- *Product available on Desertcart Croatia* *Store origin: HR* *Last updated: 2026-06-09*