Green Planet Pro-Cal — 1Ltr

Green Planet Pro-Cal — 1Ltr

Pro-Cal is Green Planet's calcium-magnesium supplement — provides the supplemental Ca and Mg that most base nutrients don't carry in sufficient quantities, particularly critical for coco coir grows where the media naturally locks out calcium. Essential for RO-water growers, soft-water areas, and any setup where CalMag deficiency (yellowing between leaf veins, brown spots, weak stems) is a persistent problem. Works alongside any base nutrient from any brand.

Why growers choose Pro-Cal:

• Calcium + magnesium supplementation — the two most commonly deficient secondary nutrients
• Essential for coco grows — counteracts coco's natural calcium lockout
• Critical for RO water — replaces the Ca/Mg that reverse osmosis strips out
• Prevents deficiency symptoms — yellowing, brown spots, weak stems
• Works with any base nutrient — brand-agnostic, media-agnostic
• Available 1L through 23L — from hobby bottles to commercial drums

Who it's not for:

If you're growing in soil with hard tap water (above 0.4 EC from the tap), you likely already have enough calcium and magnesium — adding Pro-Cal on top can push EC too high. Check your water report first. Pro-Cal is a CalMag supplement, not a base nutrient — use alongside a complete feed. For comparison: equivalent to Canna CalMag Agent, Shogun CalMag, or VitaLink CalMag in function. Dose carefully; calcium excess locks out other nutrients just as surely as calcium deficiency does.

In stock now — ships same working day from our Staffordshire warehouse with free UK delivery over £100. Pick up in-store at our Stone shop (ST15 0SR) if you're local, or click & collect at checkout.