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FloraPro™ PK+
FloraPro™ PK+
FloraPro™ PK+
FloraPro™ PK+
FloraPro™ PK+

Bloom Booster

FloraPro™ PK+

PK+ is a zero-nitrogen Phosphorus, Potassium, and Sulfur supplement used to bulk and ripen crops. The benefit of PK+ is realized at the system level: by transitioning application rates away from the Bloom base and toward PK+ in flower, you effectively remove Nitrogen delivery while keeping P, K, and S in the target range for critical flower formation and bulking. This shift facilitates a Nitrogen-tapering signal to amplify senescence and color change.

 

FloraPro PK+ (0-4-6) is a zero-nitrogen formula designed to help bulk and ripen plants by supplementing Phosphorus, Potassium, and Sulfur levels through flowering and finish. This boost is designed to regulate the on-set signal of senescence, which allows the plant to shift energy from leaf growth toward ripening.

This product is intended for use in continuous liquid feed programs for hydroponic use only. Normal feeding range is up to 10 mL/gal, depending on the growth stage. Consult FloraPro feed programs for additional information. 

Application rates (in mL per gallon) based on the FloraPro Liquid Feed Program:

Early Flower (Weeks 1–3): 2 mL
Mid Flower (Weeks 4–6): 4 mL
Late Flower (Weeks 7–8): 5 mL
Finish (Week 9): 7 mL 

Note: Adjustments may be needed based upon environmental conditions, water quality, individual grow structure and use of additional products. Feed programs are recommendations and a starting point, actual results may vary.

By transitioning application rates away from the Bloom base and toward PK+ during the flowering stage, you reduce Nitrogen delivery. This shift maintains Phosphorus (P), Potassium (K), and Sulfur (S) within the target range required for critical flower formation and bulking. This precision steering triggers natural senescence signals, facilitating a clean finish and heavy generative weight without the interference of excess Nitrogen.

Product guide

How to use this product

Review usage guidance, compatibility notes, and grower tips for this product.

Zero-Nitrogen Flower Support

FloraPro PK+ delivers phosphorus, potassium, and sulfur without adding nitrogen. This makes it a useful tool for supporting flower development while the FloraPro Liquid Program tapers nitrogen through late flower and finish.

Supports Bulking and Ripening

PK+ is used throughout flowering to support the generative phase. Application rates increase as the crop moves from early flower into mid flower, late flower, and finish, helping support flower formation and ripening.

Works with Bloom A & B

PK+ is designed to work with FloraPro Bloom A and Bloom B. As Bloom base rates decrease, PK+ helps maintain P, K, and S delivery so the program can continue supporting flower formation, bulking, ripening, and finish quality.

Support

Frequently Asked Questions

What is the guaranteed analysis of FloraPro™ PK+ and what secondary minerals does it deliver?

FloraPro PK+ is a concentrated liquid plant nutrient supplement with a guaranteed analysis of 0-4-6. It is specifically engineered to deliver high levels of Phosphorus and Potassium alongside Sulfur, providing essential generative elements directly to the rootzone during key stages of flower development.

What is the primary objective of PK+ in the FloraPro Liquid Feed Program?

The primary objective of PK+ is to act as a generative shift and ripening tool. Shifting your application rates away from the nitrogen-containing Bloom base and toward PK+ during flowering allows you to taper off Nitrogen delivery while maintaining optimal, targeted levels of Phosphorus, Potassium, and Sulfur required for prolific flower formation, heavy bulking, and ripening.

How does PK+ physiologically steer the plant to stop vegetative growth and focus on bud production?

Shifting your nutrient ratios away from the Bloom base and toward zero-nitrogen PK+ weakens the plant’s vegetative "leaf growth" signals. This precision steering regulates the onset signal of senescence, forcing the plant to shift its cellular energy away from foliage growth and redirect it entirely toward flower swelling, ripening, and mature generative weight.

What are the precise application rates of PK+ under the standard liquid feed schedule?

Under the continuous liquid feed program, PK+ is applied throughout the flowering cycle at the following graduated rates:

  • Early Flower (Weeks 1–3): 2 mL per gallon
  • Mid Flower (Weeks 4–6): 4 mL per gallon
  • Late Flower (Weeks 7–8): 5 mL per gallon
  • Finish (Week 9): 7 mL per gallon (Note: While these standard rates provide optimum steering, PK+ has a highly versatile normal feeding range that can scale up to 10 mL per gallon depending on environmental conditions, water quality, and specific crop response.
Can PK+ be used with FloraPro Powders or other base nutrient brands?

Yes, PK+ features universal versatility. While it is a core component of the FloraPro Liquid program, its zero-nitrogen formulation makes it a highly versatile, quality-reinforcing supplement that functions effectively within the FloraPro Powder program or alongside any existing base nutrient program on the market.

Is PK+ safe to run through automated fertigation panels and drip line networks?

Yes. FloraPro PK+ is a highly soluble, professional finishing part formulated specifically for commercial-scale use. It is fully compatible with fertilizer injectors, day tanks, and drip irrigation setups, and will dissolve rapidly in water with zero risk of clogging drip emitters or irrigation lines. To maintain overall system hygiene when running the complete liquid program, running TrueFlo™ alongside your feed is recommended to automate line maintenance.

Why is utilizing PK+ for Nitrogen Steering superior to using standard bloom boosters or a late-stage chloride "flush"?

Many competitor programs use heavy chloride salts to "force" a color fade at the end of a grow, which causes osmotic stress ("chemical sunburn") and results in muted, "cardboard" terpene profiles. Shifting to zero-nitrogen PK+ allows for a clean ripening phase without starving the plant of other essential minerals or exposing it to chloride-induced salt stress. By steering with precision, the plant's natural senescence and secondary metabolite pathways remain fully functional, ensuring unmasked terpene and flavonoid development.

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