Monopotassium Phosphate 0-52-34
- Regular Price
- $ 29.99
- Sale Price
- $ 29.99
- Regular Price
- $ 33.99
- Unit Price
- per
Monopotassium Phosphate (MKP) 0-52-34
A nitrogen-free, 100% water-soluble P-K fertilizer delivering 52% phosphorus and 34% potassium — purpose-built for flowering, fruiting, and quality enhancement in soil and hydroponic systems.
Ideal Applications
FEATURES
🚫 Zero Nitrogen Formula
MKP contains absolutely no nitrogen, preventing unwanted vegetative growth during critical flowering and fruiting stages when blooms and fruit quality take priority.
💎 52% Phosphorus (P₂O₅)
One of the highest phosphorus concentrations available in a water-soluble fertilizer, driving root development, flower bud initiation, and energy transfer throughout the plant.
⭐ 34% Potassium (K₂O)
High potassium improves fruit size, sweetness, color, and shelf life while strengthening disease resistance and drought tolerance across a wide range of crops.
💧 100% Water-Soluble
Dissolves completely and rapidly with no residue, making it ideal for drip irrigation, fertigation lines, foliar sprayers, and recirculating hydroponic systems without clogging emitters.
🧂 Low Salt Index
MKP's low salt index makes it safer for sensitive crops and seedlings compared to other high-phosphorus fertilizers, reducing the risk of fertilizer burn at recommended rates.
🍄 Powdery Mildew Suppression
Research shows MKP solutions can suppress powdery mildew in susceptible crops including grapes, cucumbers, melons, and roses when applied as a foliar spray during disease-prone periods.
🔬 Technical Grade Purity
Produced to technical grade standards with consistent crystalline form, superior solubility, and low heavy metal content — independently tested for heavy metal content and quality assurance.
⚖️ pH-Neutral in Solution
Unlike MAP or DAP, MKP does not acidify your growing medium or nutrient solution, making it compatible with a broader range of crops and growing media.
🌡️ Wide Crop Compatibility
CDFA-registered for use on fruits, vegetables, grains, turf, ornamentals, and hydroponic systems — one versatile P-K source across your entire operation.
🏭 Made in USA
Manufactured and packaged in California with strict quality controls, CDFA registration, and consistent nutrient analysis backed by third-party laboratory verification.
DERIVED FROM
Greenway Biotech MKP 0-52-34 is derived from a single, pure source compound. Technical grade ensures maximum solubility, purity, and consistency batch to batch.
Primary Source
Because MKP is a single-compound fertilizer, it contains no filler ingredients, binders, or added materials — what you see on the label is exactly what's in the bag.
SCIENCE BEHIND THE FORMULA
0-52-34: The Pure P-K Combination
MKP's formula is derived entirely from one compound — potassium dihydrogen phosphate (KH₂PO₄). With zero nitrogen, it delivers maximum phosphorus and potassium exactly when plants need them most: during bloom initiation, flowering, and fruit development.
🌿 Nitrogen — 0% (Intentionally Absent)
No nitrogen means no stimulus for vegetative leaf growth during bloom. This is the key advantage of MKP over MAP or DAP: it won't delay flowering, extend the vegetative phase, or dilute fruit quality with excess canopy growth.
🌸 Phosphorus — 52% (Bloom & Root Power)
Phosphorus drives ATP energy production, root cell division, and flower bud initiation. At 52% P₂O₅, MKP delivers a concentrated dose precisely when phosphorus demand peaks — from bud break through early fruit set.
⭐ Potassium — 34% (Quality & Resilience)
Potassium regulates stomatal opening, sugar translocation into fruit, and enzyme activation. Higher potassium during ripening is directly linked to improved Brix (sugar content), firmer fruit, better color development, and longer post-harvest shelf life.
Why MKP Outperforms Other P-K Sources
🆚 MKP vs. MAP (12-61-0)
MAP contains 11–12% nitrogen and no potassium. MKP has zero nitrogen and adds 34% potassium — making it the better choice for late bloom and fruit development when nitrogen suppression and quality enhancement are the goals.
🧪 Single-Salt Purity
As a single-compound fertilizer, MKP has no incompatible components within itself. Its pH-neutral behavior in dilute solution prevents the acidification issues associated with ammonium-based phosphates like MAP and DAP.
🍄 Plant Immunity Boost
The phosphorus-potassium combination in MKP strengthens plant cell walls and supports secondary metabolite production, which research associates with improved resistance to powdery mildew and other fungal pathogens.
APPLICATION RATES & DIRECTIONS
Foliar Application
| Crop Type | Rate per Acre | Rate per 1,000 sq ft | Timing |
|---|---|---|---|
| Deciduous Fruits (Apples, Pears, Stone Fruits) | 5–10 lbs | 2–4 oz | Pre-bloom & post-bloom |
| Tomatoes, Peppers | 5–10 lbs | 2–4 oz | Prior to full bloom; repeat 2–3× at 2–3 week intervals |
| Grapes | 3–10 lbs | 2–4 oz | Pre-bloom, post-bloom, 30 days before harvest |
| Strawberries | 3–10 lbs | 2–4 oz | After first blooms appear |
| Melons, Cucumbers, Cucurbits | 5–10 lbs | 2–4 oz | Just prior to bloom; repeat 2+ times |
| Potatoes | 5–10 lbs | 2–4 oz | At initial tuber formation |
| Root Vegetables (Carrots, Beets) | 5–10 lbs | 2–4 oz | Mid-season applications |
| Leafy Vegetables, Cole Crops | 1–2 lbs | 0.5–1 oz | Every 10–14 days |
| Small Grains (Wheat, Barley) | 2–6 lbs | 1–2 oz | At tillering, before boot stage |
| Almonds, Walnuts, Pistachios | 5–10 lbs | 2–4 oz | 3–4 applications: petal fall through hull split |
Fertigation & Hydroponic Rates
| Application Method | Concentration | Frequency |
|---|---|---|
| Drip Irrigation / Fertigation | 1–2 lbs per 100 gallons | Weekly during bloom/fruiting |
| Hydroponics — Bloom Phase | 100–200 ppm | Continuous in nutrient solution |
| Soil Drench (home garden) | 1 tbsp per gallon water | Every 2 weeks |
| Field Fertigation | 25–500 lbs per acre | Per crop program |
Turf & Ornamental Rates
| Application | Rate | Timing |
|---|---|---|
| Cool Season Grasses (Bentgrass, Fescue, Bluegrass) | 2–4 oz per 1,000 sq ft | Spring & fall; up to weekly |
| Warm Season Grasses (Bermuda) | 2–4 oz per 1,000 sq ft | Late spring to early fall |
| Trees, Shrubs, Roses, Bedding Plants | 1 lb per 10 gallons water | At bloom, spring push, or after transplanting |
Coverage Guide by Package Size
| Bag Size | Foliar Coverage (at 3 lbs/100 gal) | Fertigation Coverage (at 1 lb/100 gal) |
|---|---|---|
| 1 lb | ~33 gallons spray solution | ~100 gallons drip solution |
| 5 lbs | ~165 gallons spray solution | ~500 gallons drip solution |
| 25 lbs | ~830 gallons spray solution | ~2,500 gallons drip solution |
| 50 lbs | ~1,650 gallons spray solution | ~5,000 gallons drip solution |
HOW TO USE
Foliar Spray
- Dissolve MKP in a small amount of warm water first, then add to tank with remaining water while agitating.
- Fill tank to approximately half volume, add MKP, then top off with remaining water.
- If adding pesticides, add MKP first, then pesticides last.
- Check temperature — do not spray if air temperature is above 84°F (rising) or below 90°F (falling).
- Apply in the early morning or evening to minimize evaporation and leaf stress.
- Allow minimum 7 days between foliar applications.
Fertigation & Drip Irrigation
- Dissolve MKP completely in water before introducing into the irrigation line — it dissolves readily at room temperature.
- Apply at 1–2 lbs per 100 gallons of irrigation water during bloom and fruiting phases.
- Do not tank mix with calcium fertilizers (calcium nitrate, gypsum, etc.) in the same solution — apply calcium on a separate fertigation cycle.
- Flush lines briefly with plain water after application to prevent any residue buildup.
Hydroponics — Bloom Phase
- Add MKP to your nutrient reservoir to achieve 100–200 ppm additional phosphorus during the bloom phase.
- Check and adjust EC and pH after addition — MKP has minimal pH impact but verify readings.
- Do not add MKP to a reservoir that already contains calcium — mix separately and introduce to reservoir with circulation running.
- Monitor plant response over 7–10 days and adjust rate as needed.
Soil Drench (Home Garden)
- Dissolve 1 tablespoon of MKP per gallon of water.
- Apply around the base of plants, avoiding direct contact with stem tissue.
- Water in lightly after application.
- Repeat every 2 weeks during flowering and fruiting.
Pro Tip: Time Your MKP Applications to the Bloom Window
For maximum impact on fruit quality and yield, apply MKP foliar at 3–5 lbs per 100 gallons starting 7–10 days before anticipated first bloom, again at full bloom, and once more at early fruit set. This three-application window aligns with peak phosphorus demand for flower development and early cell division in the fruit. Commercial growers in the Central Valley commonly add a fourth application 30 days before harvest to drive final Brix increase in grapes and tree fruits.
When MKP Is the Right Choice
- During flowering and fruiting when you need P and K but want zero nitrogen influence
- In hydroponic bloom-phase programs where nitrogen ratios are already dialed in
- As a late-season quality booster to improve Brix, color, and fruit firmness
- For powdery mildew suppression programs on grapes, cucumbers, and roses
- When drip or foliar precision application is required and complete dissolution is critical
When to Consider Other Options
- Early vegetative growth stage — consider MAP 12-61-0 when nitrogen is also needed alongside phosphorus
- When you need calcium and phosphorus together — use Calcium Nitrate 15.5-0-0 on separate fertigation cycles (never mix calcium and phosphate in the same tank)
- When a balanced macro program is needed — a full hydroponic bundle provides a more complete starting foundation than MKP alone
MKP 0-52-34 CALCULATOR
SAFETY & HANDLING
Personal Protective Equipment (PPE)
- Wear chemical-resistant gloves when handling concentrated MKP powder or strong solutions
- Wear safety glasses or goggles — fine powder can cause eye irritation
- Use a dust mask (N95 or equivalent) when working with powder in enclosed or dusty conditions
- Wash hands thoroughly with soap and water after handling
Storage Guidelines
- Store in a cool, dry location in the original sealed container
- Keep away from direct sunlight and heat sources — MKP is hygroscopic and will absorb moisture if left open
- Reseal bags tightly after each use to prevent caking
- Keep out of reach of children and pets
- Do not store near calcium-containing fertilizers or strong oxidizing agents
Application Precautions
- Never mix MKP in the same tank as calcium fertilizers (calcium nitrate, calcium chloride, gypsum solutions) — a calcium phosphate precipitate will form and clog equipment
- Perform a jar test before tank mixing MKP with unfamiliar pesticides or adjuvants
- Do not apply foliar sprays above 84°F (rising temperature) to avoid leaf burn
- Do not apply to drought-stressed, diseased, or pest-damaged plants
- Avoid direct contact with seeds at high concentrations — MKP has a low but nonzero salt index
- Avoid spraying on young or dwarf trees at maximum labeled rates
First Aid
- Eye contact: Flush with clean running water for at least 15 minutes, holding eyelids open. Seek medical attention if irritation or redness persists
- Skin contact: Wash the affected area thoroughly with soap and water. Remove and launder contaminated clothing before reuse
- Ingestion: Do not induce vomiting. Rinse mouth with water. Contact Poison Control (1-800-222-1222) or seek medical attention
- Inhalation: Move to fresh air immediately. Seek medical attention if coughing or respiratory discomfort persists
Refer to the Safety Data Sheet (SDS) for complete emergency and handling information.
COMPLETE YOUR SYSTEM
MKP delivers pure P and K with zero nitrogen. Pair it with these products to build a complete fertility program for every growth stage.
Calcium Nitrate 15.5-0-0
Provides nitrogen and calcium — two nutrients absent in MKP. Apply on separate fertigation days to avoid calcium-phosphate precipitation.
Ammonium Sulfate 21-0-0
21% nitrogen plus sulfur for vigorous vegetative growth phases. Use before switching to MKP at bloom transition.
Epsom Salt (Magnesium Sulfate)
Supplies magnesium for chlorophyll production and sulfur for enzyme function. Compatible with MKP in the same tank.
Chelated Iron EDTA 13%
Corrects iron deficiency in bloom-stage crops without interfering with MKP's P-K delivery. EDTA chelation keeps iron plant-available across a wide pH range.
FREQUENTLY ASKED QUESTIONS
Why can't I mix MKP with calcium nitrate in the same tank?
Phosphate ions (from MKP) and calcium ions react to form calcium phosphate, an insoluble compound that precipitates out of solution. The resulting white sludge can clog drip emitters, spray nozzles, and pump filters. Always apply MKP and calcium fertilizers on separate fertigation cycles — a 24-hour gap between applications is sufficient for most systems.
What's the difference between MKP 0-52-34 and MAP 12-61-0?
MAP (monoammonium phosphate) contains 11–12% nitrogen alongside high phosphorus and no potassium. MKP contains zero nitrogen and adds 34% potassium. Choose MKP when you are at the flowering or fruiting stage and need to boost P and K without stimulating new vegetative growth. Choose MAP 12-61-0 when you need phosphorus along with some nitrogen during early growth or root establishment.
Can MKP help suppress powdery mildew?
Research suggests that MKP solutions applied as a foliar spray may help suppress powdery mildew on susceptible crops including grapes, cucumbers, melons, and roses. The phosphorus-potassium combination can strengthen plant cell walls and support immune response. MKP is often used alongside systemic fungicides to potentially improve overall program efficiency — though results vary by crop, environment, and disease pressure.
How do I avoid leaf burn when applying MKP as a foliar spray?
Follow the temperature guidelines strictly: stop foliar spraying when air temperature reaches 84°F on a rising curve (typically mid-morning), or wait until temperatures fall to 90°F on a falling curve (late afternoon). Always maintain a minimum 7 days between foliar applications and never spray stressed plants. Using sufficient water volume — targeting 350 gallons per acre for dilute sprays — helps prevent excessive concentration on leaf surfaces. Adding a non-ionic surfactant can also improve coverage and reduce localized concentration.
When is the best time in the growth cycle to use MKP?
MKP is typically most valuable from bud break through early fruit set — specifically the 2-week window before first bloom, during active flowering, and at fruit set when phosphorus demand is highest. For quality enhancement, a final application 30 days before harvest can help increase Brix and improve color in grapes and stone fruits. MKP is generally less useful during the purely vegetative stage when nitrogen and micronutrients take priority over P-K loading.
Is MKP compatible with pesticides and other fertilizers?
MKP is compatible with most water-soluble fertilizers (except calcium sources), micronutrient chelates, most fungicides, and many insecticides. Its slightly acidic character in concentrated solution can actually enhance the efficacy of some pH-sensitive pesticides. Always perform a jar test before full-scale tank mixing: combine small amounts of each product, wait 15 minutes, and check for precipitation, gelling, color change, or heat generation before scaling up.
GROW WITH CONFIDENCE
Product Quality Guaranteed
- Manufactured and packaged in California, USA
- CDFA-registered fertilizer with guaranteed nutrient analysis
- Independently tested for heavy metal content and purity
- Technical grade production standards for consistent solubility and crystalline form
90-Day Money-Back Guarantee
If you're not completely satisfied with your purchase, return the unused portion in its original packaging within 90 days for a full refund. No questions asked. See our Returns & Shipping page for details.
Environmental Responsibility
- Precision nutrient formulation reduces fertilizer runoff compared to broadcast granular applications
- 100% water-soluble formula means no insoluble residues remain in soil or irrigation systems
- Concentrated product reduces packaging waste per unit of active nutrient delivered
- Ongoing research into sustainable packaging alternatives for future product lines
Giving Back
1% of all profits support the Greenway Foundation, focused on improving educational opportunities for children. Learn more at greenway.foundation.
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