Emerald Harvest Cali Pro Bloom A 3-0-3 | 15gal

Part A of a Two-Bottle Bloom-Phase Base Nutrient System, 15gal

The bloom and fruiting phase calls for a different nutrient balance than vegetative growth, and Emerald Harvest carries the same two-bottle format it uses for Cali Pro Grow into this stage. Cali Pro Bloom A 3-0-3 is the first half of that bloom-phase pair, paired with Cali Pro Bloom B 1-4-6 to deliver complete base nutrition through flowering and fruiting.

The 15gal size is built for commercial-scale bloom-phase feeding, cutting down on how often Bloom A needs restocking across a large crop.

Key Features & Benefits

• Two-bottle bloom system — Bloom A is one half of a matched pair with Bloom B rather than a complete standalone feed.
• 3-0-3 nutrient profile — supplies part of the bloom-phase macronutrient balance, kept separate from Bloom B until diluted.
• Bloom and fruiting focus — formulated for the flowering and fruiting stage rather than vegetative growth.
• Pairs with Cali Pro Bloom B 1-4-6 — together the two bottles deliver complete bloom-phase base nutrition.
• Scalable sizing — available from a 32oz trial size up to a 15gal commercial size.

Who Should Use Cali Pro Bloom A 3-0-3

This half of the pair fits growers already running Emerald Harvest's Cali Pro Grow system who are transitioning plants into the flowering and fruiting phase.

About Emerald Harvest

Emerald Harvest, a Santa Rosa, California company founded in 2015, extended its two-part Cali Pro system into the flowering phase with Bloom A and Bloom B, giving growers already using Cali Pro Grow a matching bloom-phase pair.

Frequently Asked Questions

Do I need Cali Pro Bloom B along with this product?

Yes, Bloom A supplies only part of the bloom-phase nutrient profile; Bloom B 1-4-6 provides the rest. The two bottles are formulated to be used together rather than as standalone feeds.

When do I switch from Cali Pro Grow to Cali Pro Bloom?

Switch when plants transition from vegetative growth into the flowering and fruiting phase, following the Emerald Harvest feed chart for specific timing. Growers running the two-bottle system move from the Grow A/Grow B pair to the Bloom A/Bloom B pair at that point rather than mixing the two pairs.

What does the 3-0-3 ratio provide compared to Bloom B?

The 3-0-3 ratio supplies nitrogen and potassium while leaving phosphorus to Bloom B's 1-4-6 profile, splitting the bloom-phase macronutrients across the two bottles the same way Grow A and Grow B split vegetative nutrition. That separation is part of why the system uses two bottles instead of one.

Why does Bloom A come in sizes up to 15 gallons?

The size range from 32oz up to 15gal is meant to scale from a home grower trialing the bloom-phase pair up to a commercial operation feeding a large flowering crop. The formula itself is identical across every size.

Can I use Cali Pro Bloom A with a different brand's Part B nutrient?

It's formulated specifically to pair with Emerald Harvest's own Cali Pro Bloom B 1-4-6, and the two are balanced against each other as a matched set. Substituting a different manufacturer's second-bottle nutrient isn't something Emerald Harvest's feed chart accounts for.