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What are PK boosters, how do they work and which ones you should use

Updated: Nov 18, 2021

Why Use a PK Booster?

PK Boosters are often used to push a plant to flower earlier than it naturally would. They also help the plant to produce larger fruit and flowers, so increasing the yield from the plant. They are also used to improve the taste of the end product.

What is a PK Booster?

As we all know by now there are three key nutrients essential to growing a healthy plant, nitrogen (N), phosphorus (P) and potassium (K), also known as NPK. A PK booster focuses on phosphorus and potassium (PK). Nitrogen is most essential to the plant during the vegetative stage of growth, whereas phosphorus and potassium are needed more by the plant in the bloom stage of growth, they allow the plant to maximise its bloom and flowering potential.

Most base nutrients have an NPK profile, so adding PK to the plant earlier on and helping the plant to move to its fruiting/flowering stage sooner. A PK Booster can also do this. Phosphorus is often used to speed a plant towards maturity. Now many growers say that too much nitrogen in the later flowering stages has a negative effect on the size of flowers and fruit, so it is taken out of PK boosters

What does a PK Booster do?

What a PK Booster does best is to stimulate a natural change in the plant’s chemicals, forcing the plant to focus growth into fruits and flowers.

Now plants are excellent at regulating their nutrient uptake naturally, and the levels of nutrients in the plant determine the stage of growth the plant is in. They build up their levels of PK through the veg cycle as they mature, until they reach a set threshold, which triggers the plant to move into the flowering phase.

By adding a PK during the flower stage, you then force the already quickly matured plant to direct its growth efforts to flowers and fruits as you have given them a longer time to mature. So, when you add a PK Booster to your feeding regime around weeks 3 and 4, its already using the good work done by the PK in your base nutrient, and taking advantage of the extra flowering time to help the plant reach its full potential.

Not only does a PK booster help with bigger fruit and flowers, it also helps with root development to feed those ever-growing flowers.

What should you use?

At Biogreen we have developed a range of PK Boosters to cover the needs of the individual grower.

PK13/14 is our basic PK booster designed to give an early flower boost, fed to the plant from week 3 of flower, this PK boost can see you right the way through to week 8/9.

Flower Boost is our late flower PK booster and PK finisher in a powder form. Designed specifically to accelerate late flower development and terpene production, we have carefully added amino acids to aid the plants absorption of the nutrients. On top of this a mix of kieserite has been added which acts as a fast-acting fertiliser and a source of magnesium and sulphur. With a high PK ratio of 31/21, this PK booster should be used weeks 6-8/9 to finish the plants full flowering development.

Finally, we have one of the crowns of the Biogreen range, X-Blast. This hugely popular premium late flowering PK booster maximises the plants flowering performance, pushing it to its full potential. X-Blast provides all the essential building blocks to produce large, high quality, dense fruits. It increases sugar production, improves the natural taste and aroma, as well as the quality of the fruit. We have added Iron and copper to aid photosynthesis, boron to develop the fruit to maturity and seaweed to continuously stimulate plant growth and to increase the resistance to stress. Working perfectly in any medium, it has become many growers PK Booster of choice

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