What are Rockwool Grow Cubes?

Rockwool cubes are a type of growing medium made from recycled paper pulp. They have been used since the 19th century in various forms such as wallpaper, upholstery, carpets and many other products. Some types of rockwools are natural (such as those found in trees) while others are manufactured or synthetic materials. Natural rockwool grows at temperatures ranging from 0°C to 40°C. Synthetic rockwool is usually produced using petroleum based solvents. Its temperature range ranges from -20°C to 60°C.

How do they work?

The primary function of rockwool cubes is to provide a stable environment for plants. These cubes allow plants to grow without the need for direct sunlight or even artificial lighting.

They also act as a protective barrier between the roots and the outside world. This prevents pests and diseases from entering the cube. If these cubes were not present, then plants would be exposed to extreme conditions such as high temperatures, strong winds, floods and so forth.

When to Use Rockwool Grow Cubes?

Rockwool can be used in a wide range of situations. These include:

These cubes come in a number of different sizes to suit different purposes. For instance, young plants such as seedlings are usually placed in smaller size cubes while large plants are kept in larger ones.

Advantages of Rockwool Grow Cubes

There are a number of advantages to using rockwool over other growing mediums. These benefits are as follows:

It’s a cheap medium. Just about anyone can afford to use it. It’s also easy to come by. You don’t need special equipment such as a hydroponic system or a growing tent in order to use it.

It is mostly sterile and disease resistant. This prevents the growth of weeds, pests and diseases within the cube itself. It has excellent water retention capabilities. This means your plants will not dry out easily. It prevents the growth of algae. Because your plants won’t be exposed to direct sunlight, they won’t require the additional energy in order to photosynthesize. This will increase their lifespans.

Disadvantages of Rockwool

Just like every other product, rockwool also has its share of disadvantages. They are:

It is not biodegradable. It takes hundreds of years for rockwool to break down. Its material is extracted from ancient forests, which are being destroyed in order to make way for more rockwool fields. These cubes do not allow the flow of oxygen to the roots of your plants.

This can lead to the rotting of vital parts of the plant. It also increases the risk of root rot and other fungal diseases. Rockwool is rarely pH neutral. It often makes the surrounding soil more acidic. This can be harmful to your plants, especially if you are growing edible plants. It is not an organic growing medium and does not allow the free flow of air to the roots of your plants. The plant may suffer from a lack of oxygen if it is grown in an enclosed rockwool cube for an extended period of time.

How to Use Rockwool Cubes

The basic procedure for using rockwool cubes is very simple. You simply follow this three step guideline:

First, you need to know what type of plants you want to grow. Second, determine the number of rockwool cubes required for your plants. Finally, you need to know the correct method of watering.

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Types of Plants

There are three different types of plants that can be grown using rockwool cubes:

Seedlings – These are young plants that have sprouted from seeds. They haven’t yet started flowering. These plants require the least amount of attention and can last the shortest amount of time in rockwool before they need to be transplanted into the ground or another growing medium. If grown in rockwool, they are often transferred into soil or another medium after they reach four inches in height.

Cuttings – These are pieces of plants that can be planted and grown into an entirely new plant. They require even less attention than seedlings and can last in rockwool for a very short period of time. Transplants – These are mature plants that have already been growing in another growing medium. They can be transferred into rockwool and will continue to grow as if they were in their original growing medium. This is the preferred method for growing plants because rockwool can help them grow faster and stronger.

Number of Rockwool Cubes Needed

The number of rockwool cubes your plant needs varies depending upon the type of plant you are growing. Follow these guidelines:

Seedlings – One rockwool cube per seedling. Cuttings – Two rockwool cubes per cutting. Transplants – One rockwool cube per transplant.


Follow this three step process in order to water your plants:

First, you need to have a well-balanced watering can that is made of plastic or some other lightweight material. Using heavy duty containers to water your plants will actually do more damage than good. Second, you need to check the soil for dampness. There are two types of growers: watchers and testers.

Watchers will simply eye the soil and predict whether or not it is wet. They will also tend to their plants needs by feeling if the plant itself is wet.

Need I say more?

Gardeners who are testers will stick their fingers in the soil to see if it’s wet. Most serious gardeners own a cheap garden probe that can tell them exactly how wet (or dry) the soil is. This is the preferred method of most gardeners and you should invest in one. Third, if your soil is damp then you do not need to water your plants today. If the soil is dry, then fill your can with the appropriate amount of water and water your plant. Use the water that runs out of the pot as a measurement tool. If you are a watcher, then wait until the running water has slowed to a trickle before watering again. That means your soil is now moist. If you are a tester, then wait until the soil has sucked up all the water that you just poured into it before watering again. If you water your plant daily, this process should take no longer than five minutes the first few weeks. After that, it will only take about a minute as your plants will be able to sustain themselves for longer periods of time between waterings.

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And that’s it! You’ve just grown your first cannabis plants from seed to adulthood. Congrats!

Next we’ll go over the ins and outs of plant management.

How much will this plant grow? How tall will it get? How much will it weigh? When will it be ready for harvest?

All these questions and more will be answered.


Marijuana plants are often transplanted. This means they begin life in one container and then moved to another be it bigger or smaller. Cannabis plants can be transplanted multiple times during their lifetimes. The goal of transplanting is to give the plant the best chance at survival so that it may thrive and grow to its fullest potential.

There are several factors to consider when transplanting and they are:

The age of the plant.

The size or height of the plant.

The amount of root mass or the size of the roots.

Location, location, location!

The age of the plant dictates whether or not it should be transplanted at all. Seedlings should never be transplanted as they are still establishing a root system for themselves. This is crucial in their early lifetimes and any transplant will almost certainly kill them. Younger plants can be transplanted but this is only done if you want to put them into a bigger container.

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If this is the case then transplant when the plant is between 5 and 10cm in height. This is usually when the plant is ready to flower anyway. Just as with seedlings, any transplant at this age could prove fatal.

When dealing with older plants, height becomes a factor. Anything under 50cm can be easily transplanted without much worry of failure. At this point the plant has a good root system and can handle being transplanted into a bigger container. Just make sure the new container has enriched soil with fertilizer already in it.

If you are transplanting a taller plant however (anything over 50cm) then you run the risk of shocking the plant and this often leads to failed transplants and death. You can still transplant these large plants but take extra care when doing it. Slowly get the plant used to the new container first; this can be as simple as dipping the roots in water and then touching the containers together before finally making the big step.

When dealing with the root mass you can transplant larger plants but you’ll need to take extra care. Large plants have a massive root system developed over time. As such, it is very important that you do not damage any of these roots during the transplanting process. Large plants are also heavy and this can lead to another issue.

The weight of the plant will, naturally, leave an impression in the soil where it has been standing for some time. This means if you need to move it you will have to lift the container and with a heavy container full of wet soil (which always weighs more than you think) this can be dangerous as well as damaging to your back! To avoid these issues take the time to gradually expose the roots to dry air. Filling the container with dry water can knock the plants out temporarily so you can work without it complaining too much. Just drain out all the water before you lift the container.

Finally we should talk about location because this is very important indeed. If you want to move a plant to a different location then you must take care. Decide where you want the plant to be and dig a hole there first. Next, get someone to help you lift the container (without the plant in it!

This is very important) and move it over the new hole. Now you can very carefully lower the container down into the hole or if you prefer, your helper can do the lifting while you slowly let out the rope. Once it is in position gently put the plant inside and fill in around it. If you are particularly worried about its stability then take a piece of wood and prop up one side of the container, this will stop it from falling over as the weight of the soil pulls against it.

You must wait at least a week before you introduce a flowering trigger to large plants as they need time to recover from transplanting before being force into bloom.


If the leaves begin to show signs of brown tips then you are over-watering the plant, if the leaves begin to show signs of yellow edges then you are under-watering it.

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–Optional: Cross-Pollination–

Now we’re going to talk about a slightly advanced technique which can be used to create new and unique plants. This is cross-pollination and is quite simple, at least on paper. The concept is that you take the pollen of one plant and get it onto the pistils of a different plant. This causes a fertilization effect and can double your yield if done right.

As you can probably guess this means you’ll need two separate plants to get things started. The easiest way is to take a cutting from one plant and do a little work on it to create a second plant. Once you have both of these you can then cross-pollinate them.

The first thing you’ll need to do is take the pollen from the male part of one of your plants and apply it to the pistils of your second plant. Note that this will cause the male part of your second plant die off soon after so it is recommended that you only perform this technique on a plant if you know you do not want to keep the male parts anymore.

Once you have successfully pollinated one of your plants it will soon begin to show signs of producing a larger yield than a single plant could produce. Of course this does not come without costs. The larger yield that is produced can cause the quality to be lowered as well as the plants are more prone to disease and infestation. In addition, you will soon find seeds beginning to form on your plant and these will need to be removed by hand before they ruin the taste and feel of the product.

You may want to wait until after the plant has fully matured before you harvest it, if you are concerned about the quality of the product.

–The Law–

Plant growing and use is not illegal, but it also is not looked highly upon by the kingdom. This means that there aren’t usually guards at your local garden store asking people for their papers, but it also means that the Zalan Empire might as well be saying “We can get to it if we want to” with a side order of “Don’t even think about getting funny ideas”.

If you get caught selling drugs, making drugs or doing drugs in Zalan territory there is a very good chance you’ll end up dangling from a rope. If the crime is serious enough a “merciful” hanging will be carried out and you’ll be decapitated prior to hanging.

If it’s a minor crime you’ll still be hanged, but just left to strangle to death for your crimes.

Long story short: Don’t get caught.

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–Illegal Drugs–

Now that my lecture is over it’s time to get to the fun stuff! Bare in mind that these are NOT the only drugs out there, these are just some of the more common ones that you are likely to run into in your travels.

Also bare in mind that this is explicitly for INDOOR use at the moment. While I’ll mention the effects for out of combat, realize that most of these won’t work too well in a real fight.

Common “Restorative” Drugs

Name: Blue Dream

Effect: Euphoric, Pain Reduction, Relaxation

Origin: Zalan Empire

Common: Yes (Though has a very faint blue color)

Quantity: As much as you can carry!

Defense Against Physicians: Sadly Physicians now receive training on how to deal with this menace. So if you are using this right now, you might want to stop, because the standard “tourniquet technique” is now being used even more frequently and effectively than before. This is a special kind of rope that severs the arm of person caught in it so that they may not escape and then drops them for capture. It has a high success rate, especially since Blue Dream causes an intense feeling of pain, which makes it hard to move sometimes, let alone escape.

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This drug has been nicknamed Blue Dream due to people often dreaming when under its influence. These dreams do not occur in the normal dream state however. The drug causes you to fall into a deep sleep where you can experience your dreams. The “Real World” and “Dream World” begin to blur as you constantly visit it.

Some claim the drug opens a gateway to another dimension, where these dreams take place, though this is complete nonsense. The drug causes physical damage due to the user’s body being in a constant state of REM sleep and organs begin to fail after prolonged use.

There are rumors of a stronger version of this drug, which causes the user to not wake up after falling asleep. Regardless of whether this is true or not, the “normal” version causes physical dependence. This means if you use it a lot, your body gets used to having it, and starts to malfunction without it.

If you don’t consume more Blue Dream once this happens, you’ll die.

Name: Yellow Devil

Effect: Hallucinations, Delusions, Euphoria, Severe Muscle Relaxation

Origin: Ignan Kingdom

Common: Rare

Quantity: As much as you can carry!

Sources & references used in this article:

Effect of hydrogen peroxide on algal growth, cucumber seedlings and the reproduction of shore flies (Scatella stagnalis) in rockwool by I Vänninen, H Koskula – Crop Protection, 1998 – Elsevier

Rockwool as a substrate for greenhouse crops by C Sonneveld – High-Tech and Micropropagation I, 1991 – Springer

Fusarium equiseti GF191 as an effective biocontrol agent against Fusarium crown and root rot of tomato in rock wool systems by H Horinouchi, A Muslim, T Suzuki, M Hyakumachi – Crop Protection, 2007 – Elsevier

Effects of calcium and magnesium on growth, fruit yield and quality in a fall greenhouse tomato crop grown on rockwool by AP Papadopoulos – Canadian Journal of Plant Science, 2003 – NRC Research Press

Concept for Sustained Plant Production on ISS Using VEGGIE Capillary Mat Rooting System. by G Stutte, R Wheeler, R Morrow… – … on Environmental Systems, 2011 – arc.aiaa.org

A study on the biological control of Fusarium oxysporum using Trichoderma spp., on soil and rockwool substrates in controlled environment by RM Giurgiu, A DUMITRAȘ, G Morar… – Notulae Botanicae …, 2018 – notulaebotanicae.ro

Irrigation method of nutrient solution affect growth and yield of paprika’Veyron’grown in rockwool and phenolic foam slabs. by KS Kim, YB Lee, SJ Hwang, BR Jeong… – Korean Journal of …, 2013 – cabdirect.org

Effects of pH value and Mn application on yield and nutrient absorption with rockwool grown gerbera (refereed) by C Sonneveld, W Voogt – … Symposium Growing Media and Plant …, 1996 – actahort.org

Use of pellet or cube-type phenolic foam as an artificial medium for production of tomato plug seedlings by HM Kim, KO No, SJ Hwang – Horticultural Science & Technology, 2016 – koreascience.or.kr



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