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Black Flag Horticulture
  • Home
  • Bundle Deals
  • Growing Media
    • Coco Substrates
    • Soil Substrates
    • Rockwool & Jiffy Plugs
    • All Growing Media
  • Propagation
    • Propagators
    • Rockwool & Plugs
    • Rooting Agents
  • Environments
    • Propagation Grow Tents
    • Lighthouse Tents
    • Environments Accessories
  • Climate
    • Ducting & Accessories
    • Extraction & Filtering
    • Fans
    • Sheeting
    • Tapes
    • Temperature Control
    • Humidity Control
    • Odour Control
    • Metal Work
  • Lights
    • LED Grow Lights
    • Grow Lights
    • Grow Light Accessories
    • Shop All
  • Nutrients
    • Base Feeds
    • Root Development
    • Veg Boosters
    • Enzymes
    • Mag/Cal
    • Flowering Boosters
    • P.K
    • Plant Finishers
    • pH Regulators
    • Silicon
  • Organics
    • Organic Nutrients
    • Organic Growing Media
    • Organic Plant Additives
  • Irrigation
    • Connectors
    • Pipes
    • Chillers
  • Plant Health
    • Pest & Disease Control
    • Plant Health
  • Pots & Trays
    • Plant Pots
    • Fabric Plant Pots
    • Saucers
  • Tools
    • Tanks & Reservoirs
    • Measuring Tools
    • Plant Support
    • Magical Butter Machine
    • Harvesting
    • Metering & Timers
    • Spray Bottles & Pumpers
    • All Tools & Accessories
  • Catalogue
    • Shop All
    • Brands
    • All Collections
  • Information
    • About Us
    • Contact Us
    • New & Updates
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  • Intense Nutrients - Mag-Cal - Magnesium Calcium - 1 Litre Intense Nutrients - Mag/Cal (Magnesium & Calcium)

    Intense Nutrients - Mag/Cal (Magnesium & Calcium)

    Intense Nutrients - Mag/Cal (Magnesium & Calcium)

    Regular price From £2.50 GBP
    Regular price Sale price From £2.50 GBP
  • Shogun - CalMag - Calcium & Magnesium Shogun - CalMag - Calcium & Magnesium

    Shogun - CalMag - Calcium & Magnesium

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    Shogun - CalMag - Calcium & Magnesium

    Regular price From £2.50 GBP
    Regular price £95.00 GBP Sale price From £2.50 GBP
    Sale
  • Canna - CalMag Agent - Water Enhancement - 1 Litre Canna CalMag Agent for Balanced Calcium and Magnesium Supplementation

    Canna CalMag Agent for Balanced Calcium and Magnesium Supplementation

    Sale

    Canna CalMag Agent for Balanced Calcium and Magnesium Supplementation

    Regular price From £2.50 GBP
    Regular price £19.43 GBP Sale price From £2.50 GBP
    Sale
  • BioBizz - Bio Heaven - 1 Litre Biobizz - CalMag (Calcium and Magnesium)

    Biobizz - CalMag (Calcium and Magnesium)

    Biobizz - CalMag (Calcium and Magnesium)

    Regular price From £2.60 GBP
    Regular price Sale price From £2.60 GBP
  • Plant Magic - Magne-Cal+ - 1 Litre Plant Magic - Magne-Cal+ (Magnesium & Calcium)

    Plant Magic - Magne-Cal+ (Magnesium & Calcium)

    Plant Magic - Magne-Cal+ (Magnesium & Calcium)

    Regular price From £18.95 GBP
    Regular price Sale price From £18.95 GBP
  • Emerald Harvest - CalMag (CALCIUM-MAGNESIUM SUPPLEMENT)

    Emerald Harvest - CalMag (CALCIUM-MAGNESIUM SUPPLEMENT)

    Sold out

    Emerald Harvest - CalMag (CALCIUM-MAGNESIUM SUPPLEMENT)

    Regular price £19.99 GBP
    Regular price Sale price £19.99 GBP
    Sold out
  • ESSENTIALS PLUS - CALMAG - (Calcium & Magnesium)

    ESSENTIALS PLUS - CALMAG - (Calcium & Magnesium)

    ESSENTIALS PLUS - CALMAG - (Calcium & Magnesium)

    Regular price £7.20 GBP
    Regular price Sale price £7.20 GBP
  • Advanced Nutrients - OG Organics™ Sensi Cal Mag Xtra® (MagCal)

    Advanced Nutrients - OG Organics™ Sensi Cal Mag Xtra® (MagCal)

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    Advanced Nutrients - OG Organics™ Sensi Cal Mag Xtra® (MagCal)

    Regular price £39.99 GBP
    Regular price £44.99 GBP Sale price £39.99 GBP
    Sold out
  • British Minerals - CalMag (Calcium Magnesium Supplement) British Minerals - CalMag (Calcium Magnesium Supplement)

    British Minerals - CalMag (Calcium Magnesium Supplement)

    Sold out

    British Minerals - CalMag (Calcium Magnesium Supplement)

    Regular price £15.00 GBP
    Regular price Sale price £15.00 GBP
    Sold out
  • Athena Nutrients CaMg, Horticultural Supllies Coventry, Calcium Magnesium, Plant Care

    Athena Nutrients - CaMg

    Sale

    Athena Nutrients - CaMg

    Regular price £20.99 GBP
    Regular price £28.99 GBP Sale price £20.99 GBP
    Sale

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