Emerald Harvest Cal-Mag | 1gal

Chelated Calcium-Magnesium Supplement with Kelp Extract, 1gal

Coco coir and several other common growing media are prone to tying up calcium and magnesium even when a base nutrient program supplies adequate amounts, which is why cal-mag deficiencies show up more often in those media than in native soil. Emerald Harvest Cal-Mag adds chelated calcium and magnesium along with kelp extract, a natural source of nitrogen and other compounds, to help minimize that deficiency risk.

The 1gal size fits growers applying Cal-Mag regularly across more plants growing in coco coir or similar media.

Key Features & Benefits

• Chelated calcium and magnesium — stays plant-available in media, like coco coir, prone to tying up these nutrients.
• Kelp extract content — a natural source of nitrogen and other compounds alongside the cal-mag content.
• Deficiency-risk reduction — formulated specifically to minimize calcium and magnesium deficiency risk.
• Coco coir-focused formulation — addresses a media type especially prone to cal-mag lockout.
• Base-program compatible — layers onto any Emerald Harvest or other brand's base nutrient program.

Who Should Use Cal-Mag

This supplement fits growers using coco coir or other media prone to calcium and magnesium lockout who want a chelated cal-mag source layered onto their existing base nutrient program.

About Emerald Harvest

Cal-Mag is one of the additive-category products Emerald Harvest, founded in Santa Rosa, California in 2015, developed to address specific deficiency risks that can arise on top of its base nutrient lines.

Frequently Asked Questions

Why is Cal-Mag especially important for coco coir growers?

Coco coir naturally binds calcium and magnesium ions in exchange for the potassium and sodium in the coir itself, which can leave less calcium and magnesium available to roots than a base nutrient's guaranteed analysis would suggest. Supplementing with a chelated cal-mag source helps offset that lockout effect.

What does the kelp extract in this formula contribute?

Kelp extract is included as a natural source of nitrogen along with other plant compounds, adding a secondary benefit alongside the calcium and magnesium content. It's not the primary nutrient source in the product, which remains the chelated cal-mag.

Do I need this if I'm not growing in coco coir?

Calcium and magnesium deficiencies can occur in other media too, particularly with reverse osmosis or soft water sources that carry fewer dissolved minerals than tap water. Coco coir growers face a higher risk, but this supplement isn't limited to that media type.

How does chelation help calcium and magnesium stay available?

Chelation binds the mineral to an organic molecule that keeps it soluble and available to roots across a wider range of media pH than an unchelated mineral source. Without chelation, calcium and magnesium are more prone to binding with media and becoming unavailable.

Can I use Cal-Mag with any base nutrient brand?

It's formulated to layer onto any base nutrient program, not exclusively Emerald Harvest's own Cali Pro or Grow, Micro, Bloom lines. As with any additive, introduce it gradually when pairing it with an unfamiliar base feed.