Roots Organics HPK 0-4-3, 1 gal

Phosphate Rock & Langbeinite Bloom Booster, 0-4-3, 1gal

Phosphorus and potassium both climb in importance once a plant shifts into bloom, and Roots Organics HPK pairs two mineral sources built for that shift: phosphate rock for available natural phosphorus, and langbeinite, a potassium source mined from ancient sea beds, for potassium. The result is a 0-4-3 liquid bloom booster that keeps both ingredients minimally processed to preserve their natural qualities.

This 1gal size suits regular indoor growers running HPK as a standard part of their bloom-stage program.

Key Features & Benefits

• Phosphate rock — an available natural phosphorus source central to the formula
• Langbeinite potassium source — mined from ancient sea beds in the American Southwest deserts
• 0-4-3 NPK ratio — targets phosphorus and potassium supplementation without adding nitrogen
• Minimal processing — preserves the natural qualities of both mineral ingredients

Who Should Use Roots Organics HPK

Home and professional gardeners who want a liquid bloom booster combining two natural mineral sources, rather than a synthetic P-K blend, are the fit for HPK.

About Roots Organics

HPK sits alongside HP2 in the mineral-derived side of the Roots Organics lineup, a catalog Aurora Innovations has built from Eugene, Oregon since 2000 around natural, minimally processed ingredient sourcing.

Frequently Asked Questions

What is the NPK of HPK?

HPK carries an NPK of 0-4-3, supplying phosphorus and potassium without nitrogen. That ratio is built for the bloom stage, when P and K demand rises relative to nitrogen.

What is HPK made from?

It combines phosphate rock, a natural source of available phosphorus, with langbeinite, a mined potassium source. Both are kept minimally processed to retain their natural nutrient qualities.

What is langbeinite?

Langbeinite is a naturally occurring potassium mineral mined from ancient sea beds in the American Southwest. It's used across the fertilizer industry as an unrefined source of potassium, sulfur, and magnesium.

How is it different from HP2?

HP2 is a phosphorus-only 0-4-0 formula, while HPK adds langbeinite for a 0-4-3 phosphorus-and-potassium blend. Growers who want potassium alongside their phosphorus boost use HPK; those who want phosphorus alone use HP2.