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1Repair Windows errors before they cause bigger problems2Fix the driver behind crashes, sound loss and screen glitches3Clear out junk files and repair common Windows errorsNo. Epsom salt supplies magnesium, not calcium, so it does not treat tomato blossom-end rot. Focus instead on steady soil moisture, protecting roots, and avoiding excess fertilizer. Add calcium or adjust soil pH only when a soil test and local guidance indicate it is appropriate.
What blossom-end rot looks like—and what causes it
Blossom-end rot is a physiological disorder, not a contagious fungal or bacterial infection. It usually starts at the end of the fruit opposite the stem as a water-soaked or pale brown spot, then becomes a sunken, leathery brown or black lesion. Other microbes may colonize the damaged tissue, but that does not make the original problem infectious.
The disorder is associated with too little calcium reaching developing fruit. That does not necessarily mean the soil lacks calcium: inconsistent water, impaired roots, rapid growth, and nutrient imbalances can interfere with calcium uptake or transport.
Why Epsom salt is the wrong treatment
Epsom salt is magnesium sulfate. It supplies magnesium, not calcium, and therefore does not correct blossom-end rot. Adding it for this purpose is unwarranted; excess magnesium can also compete with calcium uptake. Do not apply Epsom salt to prevent or treat the disorder.
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- SHIPMENT CONTAINS: One 3-pound resealable bag of fragrance free epsom salt for relaxing baths and soaks
- RELAXING SOAK: Dissolves easily in warm water to create a soothing bath experience that helps relax muscles and reduce tension
- VERSATILE USES: Perfect for full baths, foot soaks, and gardening applications to provide magnesium to plants
- EASY APPLICATION: For a relaxing bath, generously pour into warm running water; for foot soaks, dissolve in a small basin and soak for 15-20 minutes
- PURE FORMULA: Contains pure magnesium sulfate with no added fragrances, dyes, or fillers for a natural soaking experience
What to do for later fruit
Keep moisture even
Water regularly so the root zone stays consistently moist, not saturated. Avoid letting the soil dry out completely and then flooding it. Adjust watering for rainfall, heat, soil texture, drainage, container size, and plant growth.
As general guidance rather than a universal prescription, UConn Extension gives a target of 1 to 2 inches of water per week in its June 15, 2025 article. Iowa State University Extension and Outreach advises about 1 to 1.5 inches weekly during the growing season; that guidance was last reviewed in January 2022. Local conditions determine what your plants need.
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- Magnesium Support for Plants – Formulated to supply magnesium and sulfur for healthy plant growth.
- Supports Leaf Color & Plant Vitality – Helps encourage vibrant foliage and balanced plant development.
- Liquid Formula for Easy Feeding – Designed for simple mixing and efficient nutrient absorption.
- Ideal for Indoor & Outdoor Use – Suitable for gardens, houseplants, and container plantings.
- Made in USA
Mulch and protect roots
Once the soil has warmed, apply organic mulch to reduce evaporation and help keep moisture more uniform. Avoid cultivating close to tomato plants, where you could damage roots and interfere with water and nutrient uptake.
Avoid excessive fertilizer
Do not overfertilize, particularly in ways that encourage lush growth or create high nutrient concentrations around roots. More fertilizer is not a reliable remedy for a calcium-transport problem.
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Rank #3
- Magnesium Support for Plants – Formulated to supply magnesium and sulfur for healthy plant growth.
- Supports Leaf Color & Plant Vitality – Helps encourage vibrant foliage and balanced plant development.
- Liquid Formula for Easy Feeding – Designed for simple mixing and efficient nutrient absorption.
- Ideal for Indoor & Outdoor Use – Suitable for gardens, houseplants, and container plantings.
- Made in USA
Test before adding calcium or changing pH
Do not add calcium or change soil pH simply because affected fruit appeared. Soil may already contain sufficient calcium, and indiscriminate calcium additions are generally ineffective, according to Iowa State Extension. Use a soil test and local extension guidance to decide whether a calcium or pH amendment is warranted.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.What to do with affected tomatoes
A fruit with blossom-end rot will not recover. Remove it if you wish, then concentrate on growing conditions for fruit that develops later. If the symptoms do not match the characteristic lesion or the diagnosis is uncertain, contact a local plant diagnostic service rather than assuming it is a nutrient disorder.
Quick Recap
Best Value
- AGRICULTURAL GRADE EPSOM SALT (MAGNESIUM SULFATE): High-quality magnesium sulfate designed for outdoor use to support healthy plant growth and soil balance.
- SUPPORTS PLANT GROWTH & GREENING: Helps promote vibrant color, stronger roots, and improved nutrient uptake in gardens, lawns, and potted plants.
- VERSATILE FOR GARDENS & LAWNS: Ideal for vegetables, flowers, shrubs, trees, and grass—use in soil, as a foliar spray, or when planting.
- RESEALABLE 18 LB BULK BAG: Large, easy-to-store bag designed for repeated use across your yard, garden beds, or landscaping projects.
- MADE IN THE USA: Manufactured in the USA with consistent quality for reliable performance season after season.
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- PREMIUM QUALITY INGREDIENTS – Cz Garden Magnesium Sulfate is a water soluble, high purity fertilizer designed to boost the healthy development of all your indoor flowers, lawn, and garden vegetables.
- 100% WATER SOLUBLE - GREENHOUSE GRADE – High Purity, Premium Quality fertilizer. Beware of lower grade Agricultural Grade Calcium Nitrate that leaves oily skim on your solution, irrigation equipment, and plant roots.
- 10% MAGNESIUM + 13% COMBINED SULFUR FERTILIZER promotes green leafy growth and hardy plants. Get lush vegetation in your home garden with our high-efficiency Magnesium Sulfate Fertilizer
- 321 FEEDING SCHEDULE - Perfect for Hydroponics, Drip Irrigation Flood & Drain, NFT, DWC, Soil, Coco, Earthbox, Tower Gardens, etc.
- RESEALABLE, EASY POUR PACKAGING: Cz Garden Magnesium Sulfate fertilizer comes sealed in a 5LB heavy duty resealable pouch. Pour the necessary quantity with ease and store the rest for future use.
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