MKP Monopotassium Phosphate 1 kg

The precision nutrient for the most critical stage of growing. Crystalline MKP (monopotassium phosphate), with a composition of 52% P / 34% K, combines two highly concentrated sources of phosphorus and potassium in a completely nitrogen-free formula – making it the ideal nutrient for fruit set and development, when excess nitrogen would be harmful.

It dissolves completely in water without residue and is compatible with any fertigation or hydroponic system. Sold in a 1 kg pack.

Technical Features

• Nutrient: MKP – crystalline monopotassium phosphate
• Composition: 52% P (phosphorus) / 34% K (potassium)
• Nitrogen: zero – no nitrogen in the formula
• Pack: 1 kg
• Vegetative stage dose: 235 g per 1000 litres
• Fruiting stage dose: 470 g per 1000 litres
• Form: crystalline – dissolves fully without residue

What does MKP do for plants?

MKP is unique among hydroponic nutrients for two reasons: its exceptionally high phosphorus concentration (52%) and its complete lack of nitrogen. This combination makes it indispensable at stages when plants need phosphorus and potassium without the vegetative push that nitrogen would cause:

• Fruit set – highly concentrated phosphorus stimulates fruit set and development after petal fall
• Quality ripening – potassium improves fruit colour, flavour and sugar content
• No nitrogen – does not trigger unwanted vegetative growth during fruiting
• Complete crystalline dissolution – leaves no residue and does not clog irrigation systems
• Final growing stage – ideal for tightly controlling nutrient supply in the last weeks before harvest
• Stimulates flowering – in the vegetative stage, the high phosphorus content favours the transition to flowering

How do you control these parameters?

Nutrient solution

The plant consumes the solution, and every day the volume in the tank drops. This volume should be topped up every day with water, not with nutrient solution. Plants absorb much more water than nutrients, and since the nutrient solution is saline, topping up with solution every day salinises it until the dissolved salts exceed what the roots can tolerate. If this happens, plants stop growing – not from a lack of nutrients, but because of an excessively high osmotic potential at the roots.

Control the pH of the nutrient solution

As they take up nutrients, plant roots change the pH of the nutrient solution. The pH indicates how acidic or alkaline the nutrient solution is. Plants develop best between pH 5.5 and 6.5, and as they grow they change the pH of the solution. That is why the pH should be measured every day after topping up the solution with water. If it is outside the 5.5–6.5 range, adjust it with acid if above 6.5, or with base if below 5.5.

Control the electrical conductivity of the nutrient solution

As plants grow, the nutrients in the solution are used up and the solution becomes depleted. Eventually the solution can no longer supply the nutrients the plants need. At that point the solution should be replaced. One of the biggest problems is knowing when to change it.

A solution containing salts (nutrients) can conduct electric current. The higher the concentration of dissolved salts, the greater this conductivity. So a drop in electrical conductivity tells you when the nutrient solution needs changing. The easiest way to know the nutrient concentration is to use a conductivity meter.

One of the main reasons growers choose water-culture systems is that growth and maturity are usually 15–25% faster. Growers can still reach the desired plant size with a short vegetative period. So to get optimal early production from these systems, using the right nutrient mix and having the right conditions matter far more.