FoxFarm Big Bloom Fertilizer 0-0.5-0.7 | 5gal - Concentrate - OMRI Listed

OMRI-Listed Bloom Booster with Bat Guano and Earthworm Castings, 5gal

FoxFarm Big Bloom is a low-rate liquid concentrate -- just 0-0.5-0.7 on the NPK scale -- built around bat guano and earthworm castings rather than a heavier synthetic nutrient load. It's OMRI Listed and CDFA registered, and unlike a feed timed narrowly to one growth stage, it's meant to run from seedling through harvest, with particular value during bloom and seed formation.

The 5gal container suits large-scale operations that go through Big Bloom steadily.

Key Features & Benefits

• 0-0.5-0.7 NPK — a deliberately light nutrient load, since the value here is in the organic inputs rather than raw macronutrient concentration.
• Bat guano and earthworm castings — supply trace nutrients and organic matter alongside the base NPK.
• OMRI Listed and CDFA Registered — eligible for certified organic growing programs.
• Runs the full growing cycle — can be applied from seedling through harvest rather than during one narrow stage.
• Pairs with Grow Big and Tiger Bloom — completes FoxFarm's core three-part soil liquid feeding program.

Who Should Use Big Bloom

Growers already feeding with FoxFarm's soil liquid program, or anyone wanting an OMRI-listed organic input that runs the whole season rather than one stage, are the fit for Big Bloom.

About Fox Farms

Big Bloom is one leg of the three-part liquid feeding program FoxFarm has offered since its 1984 founding in Humboldt County, California, built alongside Grow Big and Tiger Bloom.

Frequently Asked Questions

Is Big Bloom certified for organic growing?

Yes, it carries both OMRI Listing and CDFA registration, making it eligible for certified organic programs. That holds across all four package sizes, from the 32oz bottle up to the 5gal container.

Why is the NPK on Big Bloom so much lower than Grow Big or Tiger Bloom?

Big Bloom is built around bat guano and earthworm castings rather than a concentrated macronutrient load. Its role in the feeding program is to supply trace nutrients and organic matter alongside the other two products' heavier nitrogen or phosphorus concentrations.

Can I use Big Bloom the entire season, or just during bloom?

It's formulated to run from seedling through harvest, though many growers notice its biggest impact during the bloom and seed-formation stage. There's no need to hold off applying it early or stop once flowering ends.

How does Big Bloom fit with Grow Big and Tiger Bloom?

The three products form FoxFarm's core soil liquid feeding program, with Grow Big driving vegetative growth and Tiger Bloom driving the bloom-phase phosphorus load. Big Bloom runs underneath both as the organic-matter component for the full cycle.