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PK-Boosts | Plant-Magic

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PK's, Boosts and PK Boosts

PKs, Boosters and PK Boosters

During flowering plants change how they use energy and therefore the nutrients that are needed.

The plant switches their focus from growing towards light, to creating fruits and flowers. The change in growth focus brings with it a switch in nutrient requirement. Changing the nutrients provided to the plant can dramatically improve quality and quantity of the yield of fruits or flowers.

There are several types of products that promise to improve your yield and give you the best results. The question is what actually are they, and do they work?


What is a ‘PK’ and is it different to a ‘Booster’?

A  PK is a fertiliser with  high levels of Phosphorus (P) and Potassium (K). Phosphorus  helps with the energy transfer processes helping the plant to focus its energy on growing and maturing fruit.

Potassium is responsible for yield and fruit maturity, as well as several chemical reactions the plant performs to create flowers and seeds.

Adding these elements can kick-start fruiting and flowering . By adding higher amounts of these two elements during the flowering stage, a higher yield can be achieved.

Note that a PK can help to improve yields, but without a healthy plant, at the right stage of maturity, in the right environment, an increase in yield can be difficult or even impossible.

In hydroponics, the two most common types of PK are an approximate 1:1 ratio (often a 13/14 type), and the 1:2 ratio (a 9/18 or 4-8 type).

The 13/14 fertiliser came from field trials to replace the phosphorus lost to leaching and forming of insoluble phosphorus in soil. These are rather simple pH neutral fertilisers.

The 9/18 fertiliser is a more modern approach specifically developed for hydroponic and recirculating systems because phosphorus availability is higher in these grow systems than in pots and soil or open ground, and therefore the ratio of potassium can be higher. The higher potassium levels can give higher yields), but require a more complex formulation to remain neutral and therefore they usually have a higher price than a 13/14.

A ‘Boost’ or ‘sugar stimulant’  can  trigger changes in the plant and increase metabolic rates (the rates of chemical reactions).

Unlike a PK, there’s no formal definition and so a variety of products are often described as a ‘Booster’. Most are derived from plant extracts which don’t need to be listed on the label, (unlike N P & K) so knowing what’s inside is almost impossible.

Synthetic Plant Growth Regulators (PGRs) which are used in some Boosters do need to be registered. These have been developed to stop vertical growth and encourage the plant to focus on producing more flowers.

There are many different types of Boosters with PGRs and they do not have a good reputation among some growers but it may be wrong to put them all into the same pot, as not everything out of a laboratory is bad. Just think of the advances in medicine due to synthetic chemistry!

Many boosts are based on plant extracts to amplify signals and trigger hormones that help the plant to produce more fruit. The most popular ones are based on seaweed, which for years has been used as a natural supplement, due to its blend of vitamins, hormones and trace elements.

Some products combine a PK with Booster ingredients to increase yield and metabolism. These are often referred to as PK boosters; however confusingly pure PK products are also often called PK boosters. Growers need to take care not to use two products that do the same thing and over-fertilising your plants which can lead to nutrient burn. Always check the label for an analysis of what’s inside. Avoid using two products at the same time that both contain high PK levels, unless instructed to do so by the manufacturer. You can use a PK and a Booster product together, so long as the PK levels on the Booster label are fairly low (less than 1% P or 1.5% K)

Should I use PKs and Booster?

Most hydroponic growers do use a PK because hydroponics has become focussed on growing the maximum crop yield possible.

The more important question is How should I use PKs and Boosters? PK products are often quite strong and should therefore be used carefully, ideally only when the plant is strong and healthy and following the manufacturer’s guidelines.

The variety of Booster products available is where it gets tricky. Some companies use synthetic PGRs in products without declaring it on the label, which is illegal. Depending on which PGR they’re using there may be risks to plant or human health.. There is no conclusive way to tell if the bottle you are holding has such chemicals without scientific analysis. However to help you choose the right products, pick products from companies that you trust. Secondly if you are unsure, conduct a side by side grow trial (e.g. one tank with your regular set-up and one tank with the new product). This will help you to see whether each new product is actually working for you, if something sounds too good to be true, it probably is. Lastly talk to other growers, retailers  and manufacturers.

Plant Magic Ignition

Ignition is a new pre-flowering booster from Plant Magic that has been formulated and tested to boost plant growth in a healthy and controlled way.

Using naturally derived substances only, Ignition gives you an alternative to other boost products and is suitable to be used alongside a PK. We only recommend using it at the right point in time which delivers much better value than any other boost product in the market. 

Our Blog: Hydroponic Tips & Tricks

Whether you are an expert who already has a thriving crop of healthy plants, or you are trying to grow your very first hydroponic yield, we can help you to grow the strong and healthy crops you have always wanted.

Here at Plant Magic Plus, our team of gardening experts work very hard behind the scenes to provide you with the high quality nutrients, additives and growing media that will help you to get the most out of your growing plants.

But we understand that successful horticulture is about more than just having good quality chemicals, nutrients or fetilisers, that's why we have written this blog to provide you with the insights, tips and techniques you will need to give your garden that extra magic touch.

From helpful advice about watering your plants in soil and a guide to magnesium nutrients, to top tips about growing hydroponic vegetables and a comprehensive overview of microbes, we’ve got everything covered.


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