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Green Planet Nutrients Pro-Cal, 4 Liter

Item #: PC04

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Green Planet Nutrients Pro-Cal, 4 Liter

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Pro-Cal is an excellent supplemental source of Calcium, Magnesium and Iron. Plants engaged in rapid growth can often come up short on these essential elements so supplementation is a great idea. The savvy grower makes Pro-Cal a must have in their arsenal of plant growing weapons.

How does it work?

Plants undergo a lot of stress and rapid assimilation of nutrients in their quest to build cell walls, produce chlorophyll, conduct photosynthesis, divide cells and other important functions. Calcium is an element that isn't very mobile within the plant and needs good flow of fluids throughout the plant to pull it to the areas to which it is needed and more importantly the calcium needs to be in a form that the plant can easily transport. It is of no use if there is an ample supply of calcium but that the plant can't uptake it. Pro-Cal has solved this issue so that our calcium source is readily available and married with extra magnesium and fully chelated iron.

Why it works? Pro-Cal works because it contains the following:

- Calcium is sourced from Calcium Nitrate. Calcium is an essential part of the plant's cell wall structure where it forms the glue (calcium pectate) that holds cells together making it essential for new growth, improves the absorption of other nutrients by the roots and their translocation within the plant. It activates a number of plant growth-regulating enzyme systems, helps convert nitrate-nitrogen into forms needed for protein formation and contributes to improved disease resistance.

Calcium is an intracellular messenger as well and can send a signal from one cell to another telling other cells how to react or interact. It also provides for the transport and retention of many other elements. Calcium, magnesium and potassium live in a delicate balance within plants. Too much of one will inhibit the other two. Finally, calcium is a co-factor in many enzymatic reactions. Its presence is needed to turn an enzyme on or off and allow it to catalyze a reaction.

Most growers incorporate higher levels of Pro-Cal (around 50 to 200ppm) during the first two weeks of bloom. This is when the plant takes up a higher concentration of calcium and magnesium to help facilitate the rapid division of cells, changing the plant from a vegetative state to a reproductive state. Also, during main flower set four to six weeks into the flowering process, additional Pro-Cal is required. It is a great idea to just make it part of your weekly regime.

- Magnesium is derived from Magnesium Nitrate providing a readily available source of both elements. Magnesium is part of the chlorophyll in all plants. Magnesium is the central core of the chlorophyll molecule in green plant tissue and essential for photosynthesis. Thus, if magnesium is deficient, the shortage of chlorophyll results in poor and stunted plant growth. Magnesium also helps to activate specific enzyme systems. Enzymes are complex substances that build, modify or break down compounds as part of a plant's normal metabolism. Enzymes are essential for every process in a plants life. Unless enzymes are active everything grinds to a halt.

Fe EDDHA - Fe EDDHA or Iron Ethylenediamine- N,N' - bis(hydroxyphenylacetic acid)
- Is a mouthful but is a very important substance. Iron is essential for chlorophyll production therefore goes hand in hand with Magnesium. The problem with Iron is that it is very reactive with other minerals and will lock up with other elements especially Phosphorous thus rendering it unavailable. Therefore Iron needs to be chelated or protected in a way that makes it available to the plant across a wide pH range.

Iron can be toxic at very low pH values and completely non available at high pH values, to get around this and to keep the plant happy we use a chelate called EDDHA which binds Iron and protects it from other elements and keeps it available for the plant in a pH range of 3.5 to 9.0. Very important if you are using fertilizers in soil where pH values can drift into the alkaline zone.

Fe EDTA - Fe EDTA or Iron Ethylenediaminetetraaceticacid
is also a chelate that is used to keep Iron available in a pH range below 7.5 which is ideal if you are using hydroponics. Pro-Cal utilizes different chelates to make sure that the elements are always in a useful form and are not wasted.

- Also known as Fulvic acid, plays a vital role as a chelater of essential minerals and organic compounds allowing them to pass through cell membranes much more efficiently. Fulvic acid stimulates enzyme production critical for plant functions. One of the most important functions of Fulvic acid within Pro-Cal is to keep the calcium fully chelated so that is more easily available for the building of new growth.

Key Points:

  • Thickens cell walls
  • Helps form Calcium Pectate
  • Fully chelated Iron
  • Important source of Magnesium
  • Noticeable size increase
  • Improved enzyme function
  • Coco Coir approved
  • Powerful formulation
  • Cost effective

How to use it?

Pro-Cal is the ultimate in calcium magnesium supplementation and should be used on a regular basis with your Green Planet Nutrient program. Pro-Cal is used throughout the vegetative and flowering stages, ceasing use in the last week of the flowering stage which is usually a flush week incorporating Finisher, Liquid W-8, Zyme and water.


Brand Green Planet Nutrients
Weight (lb.) 9
Free Shipping No
N-P-K 1.1-0-0
Nutrient Application Hydroponic and Soil Nutrient
Nutrient Type Organic Based
OMRI Certified No
Nutrient Material Type Liquid

Green Planet Nutrients Pro-Cal, 4 Liter Videos

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