• All our products are manufactured in California, USA
• Tested by independent third-party laboratories for quality assurance
• Registered with the California Department of Food and Agriculture (CDFA)
• Rigorously tested to ensure products are free from heavy metals

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• Biodegradable packaging
• Precise nutrient formulation to reduce runoff
• Support for eco-friendly farming methods

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Ferrous sulfate is a water-soluble iron fertilizer containing 20% iron in the Fe²⁺ form, which plants can readily absorb. Iron is essential for:

• Chlorophyll production: Iron is required for chlorophyll synthesis, giving plants their green color
• Photosynthesis: Acts as a catalyst in the photosynthetic process
• Enzyme function: Component of many enzymes involved in energy transfer and nitrogen fixation
• Respiration: Essential for cellular respiration and energy production

Without adequate iron, plants develop iron chlorosis - yellowing between leaf veins while veins remain green, starting with young leaves.

Iron deficiency symptoms are distinctive and include:

• Interveinal chlorosis: Young leaves turn yellow between veins while veins stay green
• Progression pattern: Starts with newest growth, older leaves may remain green
• Severe cases: Entire leaves turn white or yellow, then brown and die
• Stunted growth: Overall reduced plant vigor and size
• Poor fruit/flower production: Reduced yields and quality

Common in alkaline soils (pH above 7.0) where iron becomes locked up, waterlogged soils with poor aeration, and soils high in phosphorus or heavy metals that interfere with iron uptake.

Application method depends on your specific needs:

• Soil application: Work into soil around plants at 1/4-1 lb per 100 sq ft. Best for long-term correction and pH adjustment
• Foliar spray: 1-2 tbsp per gallon provides quick green-up within 3-7 days. Ideal for rapid correction
• Tree injection: For large trees, apply 1/2 cup per inch of trunk diameter under the drip line
• Timing: Apply in spring when growth begins or when deficiency symptoms appear

Important: Ferrous sulfate can stain concrete and stone surfaces. Sweep off hard surfaces immediately after application.

Ferrous sulfate acidifies soil through oxidation and hydrolysis reactions:

• When applied to soil, ferrous sulfate oxidizes to form sulfuric acid
• This releases hydrogen ions (H⁺) that lower soil pH
• More effective than elemental sulfur as it works faster
• Particularly useful for alkaline soils where iron availability is limited
• Dual benefit: provides iron while creating conditions for better iron uptake

Use our pH adjustment table to determine exact rates based on your soil type and current pH level.

Yes, ferrous sulfate is an effective, natural moss and algae control:

• Lawn moss: Apply 5 lbs per 1000 sq ft, moss turns black and dies within 7-10 days
• Roof/structure moss: Mix 3 oz per gallon water and spray. Rinse after 24 hours to prevent staining
• Algae in ponds: Disrupts photosynthesis, controlling algae growth naturally
• Benefits: Unlike chemical herbicides, also provides iron to grass and acidifies soil
• Caution: Will stain concrete, brick, and stone surfaces if not rinsed promptly

Best applied in cool, moist conditions for maximum effectiveness.