At GrowGeneration, our staff is hand picked and tested for their grow expertise, and each is an expert in his or her own area of operation.  After years of experience, we’ve come to realize that our customers need more than just simple answers to FAQs.  Please see the menu of resources below for information we’ve gathered on a wide range of topics that come up most often when we talk to growers, from beginners to experts, every day.

Environmental Requirements

Whether you are cultivating on a commercial level or at home, there are certain requirements that must be met to create an environment that is conducive for whatever you are growing. The basic requirements necessary to cultivate almost anything would include proper lighting, soil or medium, water, air, and nutrients.

Once your environment is set up properly with these essentials, most will experience successful results right away. Further tweaking, or dialing in certain variables, will further results and provide more consistency. Let’s examine each component to determine what is necessary to get started.

Water Quality

To successfully grow amazing plants, good water quality is absolutely necessary. Depending on geographical location, water quality varies immensely. Doing a proper evaluation of the quality of your water source is essential before setting up. There are certain things to consider such as the amount of solids dissolved in your water supply. This can be measured by parts-per-million (PPM), Total dissolved solids (TDS), or Electro conductivity ( EC) . You will also want to test the initial PH of your water. Proper pH is essential for proper nutrient uptake, as the plants cannot absorb any nutrients given to it without the pH being in range. The pH scale is measured from 0 to 14 with a lower number being more acidic and a higher number being more alkaline or basic. 7.0 is neutral. For soil applications, the pH range is from 6.0 to 7.0, while in hydroponics the pH range is 5.5 to 6.5. You can adjust the pH of your solution with pH up and pH down adjusters. Sodium hydroxide (KOH), is used to adjust pH up, While phosphoric acid (H3PO4) is commonly used to adjust pH down. Use extreme care with these adjusters as they can cause chemical burns. Always wear protective clothing and equipment such as glasses and gloves.

Just like the Richter scale used to measure seismic activity, every full point change signifies a 10 fold increase or decrease in strength. For example, water with a pH of 5.0 is 10 times more acidic than water with a pH of 6.0, 100 times more acidic than water with a pH of 7.0 and 1000 times more acidic than water with a pH of 8.0. With such an intense change between each point, accurate measurement and control are essential to a healthy grow. There are several different ways to measure the pH of your water. You can use a continuous monitor which keeps the probes in your solution 24 hours a day giving you complete real-time monitoring of the pH, dissolved solids, and temperature of the solution. You can also get more portable PH and conductivity pens and probes to use as well. There are several brands out there, the most commonly used our Bluelab and Hannah. U can also purchase soil probes for testing soil and medium pH. Some other methods included adding an indicator to the water and measure the color change. It is effective, but not as accurate as quality instrumentation. It is always recommended to use as accurate methods as possible to avoid any detriment in your grow. Many growers choose to utilize reverse osmosis (RO) systems to eliminate the headache of poor water sources. RO water is free from almost, if not all, solids and contaminates such as chlorine and fluorine. By doing this, the grower is free to add whatever they choose to the water, offering complete control.


Proper lighting is absolutely critical to ensure terrific growth and flowering. Certain crops will allow you to use minimal lighting, such as sprouts, grasses, and leafy greens. Other crops, such as flowering and fruiting plants, will require more intense lighting to give a substantial harvest. There are various types of lights depending on situation.

First, there is high intensity discharge, or HID lighting. There are a few types of lights within this category. To start, there is metal halide or MH lighting. This is available in a variety of wattages and intensity and is usually used for vegetative growth since it provides a blue dominant spectrum, simulating a summer lighting when plants are usually growing vegetatively.

For flowering, most people will traditionally switch to high pressure sodium, or HPS lighting. This is more dominant in the red spectrum, simulating autumn lighting, when plants finish fruiting. Both types of lighting are commonly available in 250w, 400w, 600w, and 1000w versions. They are offered in several different styles depending on which application they are used.

Something worth noting is that many growers now choose to explore flowering or growing full-term (vegetative and flowering) using a ceramic metal halide (CMH). Even though this is a MH type of lamp, the ceramic component assists in emitting a higher red spectra, essential for flowering especially. These are commonly available in 315w and 630w versions. This also allows for more coverage using less electricity, making them highly efficient.

Another type of lighting that many growers are starting to use, and is becoming more popular, is LED lighting. These, too are offered in a variety of shapes and sizes depending on the growers’ needs. LED lights tend to be more expensive initially, but many experience lower operating costs such as cooling and electricity use. On a commercial basis, some states even offer substantial rebates for using LEDs. They are also able to be placed closer to the canopy of the garden for maximum light penetration. You are also able to run more lights for the same cost.

Lastly, many enlist in the use of T5 high output fluorescent lighting. These are not as strong as the other types of lighting previously mentioned, but provide substantial results in the earlier phases of growth, such as seedlings, cuttings, as well as juvenile and later vegetative growth. Other advantages for using this type of lighting includes lower electrical consumption and lower temperatures within the environment. They are used by both commercial and residential growers alike.

Results can be achieved with other types of light outside of these recommendations, but may not provide as substantial results as higher output lighting. Remember, you are trying to recreate the sun’s intensity!!

Airflow and Temperature

Just as having a powerful light and quality water is important, airflow is no exception. It is very important to maintain good air movement and circulation within the environment to control temperature and humidity, as well as provide an adequate supply of carbon dioxide (CO2). You do not need to create a powerful vortex or wind tunnel to achieve great results. Depending on the size and magnitude of the operation, anything from a simple fan in the room up to a powerful HVAC system is appropriate. Having fresh air come into the environment as used, old air is exhausted out is ideal. It is important to calculate the cubic footage within the environment to be able to get a system rated high enough to accommodate the given space. It is a simple calculation of Length X Width X Height = Cubic Footage. For example if I have a 10 x 10 room that gives me 100 ft.², and if the ceiling is 8 feet tall that gives me 800 ft.³. It is as simple as finding an exhaust fan rated with a high enough cubic feet per minute (CFM) to accommodate my environment. We recommend Can Fan brand, but there are many different brands to accommodate any situation and provide terrific results. Most plants prefer an environment between 70 and 80° with the humidity of 40 to 55%, depending on stage of growth and crops being grown. Other equipment used to keep the environment stable will be heating and cooling sources as well. Most of these variables can be controlled automatically as well as manually depending on the individual needs of each grower.

CO2 enrichment is desired by many growers because it allows the plans to keep photosynthesis up at a higher rate, especially if temperatures rise too much. It also allows gas exchange between the plants and the environment. Regularly exhausting the room and replenishing it with fresh air allows for transpiration to take place effectively. Transpiration is when water vapor escapes from pores under the leaves known as stomata. Evaporation will take place within the environment whether it be from a reservoir full of water in hydroponics applications or soil having water evaporate as well. A plant breathes by taking CO2 in through the opened stomata and releasing water and oxygen into the environment. The larger the plant, the more stomata it has to make this exchange. Carbon dioxide can be provided in a few ways. Most hobbyists and professional growers use CO2 tanks with regulators and timers to sync dispersal with exhaust cycles. CO2 is heavier than air, so it must be dispersed from above the canopy. To avoid having the fans exhaust the CO2 before the plants have a chance to use it, the fans will shut off for a brief duration to allow the plants to utilize the abundant CO2. Once this has occurred, the CO2 regulator will stop dispersing and the exhaust will come back on. This will continue to happen cyclically, depending on the grower and the crop being grown.

Humidity directly relates to temperature. Many flowering plants prefer a relative humidity of 40%- 60%. The lower range discourages pests and other problems. When humidity is high, water evaporates slower. This causes the stomata to close causing transpiration to slow down, along with plant growth. When the air is drier water evaporation is quick. This stimulates the stomata to open, and increasing transpiration and fluid flow as well as growth.

Soils and Medium

A medium is anything that you plant your plants into true provide a source of nutrients or simply just to provide stability for the plant, depending on application of soil grown or hydroponically grown crops. There are a variety of mediums to choose from, depending on what it is you wish to cultivate. Many folks will opt to grow in soil their first time for a couple of reasons. One is soil has more forgiveness to error than hydroponic applications. Hydro will definitely require more attention, but can provide grander yields.

Soil amendments are added to a mix to provide certain characteristics of the overall soil composition. Perlite is an amendment that works especially well for aerating soil. It provides excellent drainage during all phases of growth and does not promote salt buildup from fertilizers. It is an amorphous volcanic glass, meaning it does not have a crystalline structure. It crumbles like chalk in stead of breaking like glass. Another type of amendment is sand which is usually heavier and provides more weight to the overall soil. It tends to wash into soil pockets and will accumulate on the soil surface.

Light- weight expanded clay aggregate (LECA), is expanded clay pellets used to assist in drainage and provide oxygen within the medium. They are inert (No nutrient value) and are commonly used in hydroponics.

Vermiculite is another popular additive used to hold moisture. If used in larger quantities, It cannot be as cost-effective as other mediums. It holds water, nutrients and air and gives substance to high porosity soils. By itself, it will hold too much water, But works well when mixed with excellent draining medium. Peat is another commonly used amendment. It is relatively affordable and provides excellent texture to almost any application as it is lightweight and fluffy. It is similar to another popular medium called coco coir or coconut fiber. It holds so much water and air at the same time and many gardeners prefer to mix it with soil. Others prefer to use it straight. It is usually inert. This makes it excellent for hydroponics or soil used methods awake.

Soil is usually composed of Peat, perlite, and Coco. Another popular type of medium is Rockwool, which is created by heating molten rock to high temperatures and having steam or air blown into it. Other techniques will spin the molten rock in high-speed spinning machines, resulting in a product that is very porous and fibrous such as insulation or cotton candy and can be pressed into slabs, cubes, or pellets. There are still other amendments and products folks will use as medium such as gravel or styrofoam. The ones we have just reviewed are the most commonly used, as well as usually being readily available.

Nutrients and Additives

There are almost countless ways to provide nutrients to your crops. Whether you are using hydroponics or soil based cultivation, the nutrients will vary. If you are growing in the soil, many people choose between salt based fertilizers, organic-based fertilizers, or a hybrid system of both. This is usually dictated by style of gardening and The growers preference. We sell a variety of nutrients on both ends of the spectrum. Some people find growing with salt based nutrients when they start out provide very excellent results and gives them a chance to witness the physiology of whatever they are growing very easily. Organics require several different approaches and techniques to achieve results, but usually will provide more flavorful crops with less yield, but a cleaner product. Either way, there are certain nutrient requirements throughout various stages of growth and certain elements are required during these different stages. Let’s take a look at which elements the plants use the most.

First of all, we need to make the distinction that there are macronutrients and micronutrients that the plants will use.

Macro nutrients are what the plants consume in large quantities, and micro nutrients are what they consume in smaller quantities.

Macro nutrients are usually referred to as N-P-K. This indicates nitrogen, phosphorus, and potassium, respectfully. You will these ratios on the front of almost any fertilizer.

For example, a bottle that reads 20-6-15 has a higher ratio of nitrogen to the others. Likewise, a label that says 0-50-30 is a higher amount of phosphorus in it. The plants also use an incredible amount of calcium and magnesium as well. Micro nutrients will include silica, zinc, iron, manganese, boron, copper, molybdenum, chlorine, cobalt, nickel, slamming them, sulfur, and sodium. So what do all of these do? Nitrogen is responsible for leaf, stem, and vertical growth. Phosphorus fuels photosynthesis and flowering. Potassium helps produce and combine sugars, starches, and carbohydrates. This promotes cell division. Calcium contributes to strong cell walls, root walls, and root growth. Magnesium is the central atom in the chlorophyll molecule. Plants use a lot! Magnesium also aids in nutrient use and transport as well. Sulfur is the building blocks of proteins and hormones. Other elements are used for enzyme and protein synthesis, nitrogen fixation and transport, as well as photosynthesis.

Organic sources for these elements include, but are not limited to, cow and chicken manure, bat and seabird guano, worm castings, molasses, seaweed and kelp, and Azomite, which is a great source of trace minerals.

Salt based fertilizers are available in complete sets consisting of seven or eight main components. This will usually include a base nutrient system providing the NPKs and trace elements for the plants.

There’s also potassium silicate which is a supplement used to strengthen the cell walls in the stem of the plant allowing it to provide more support for fruits and flowers as well as build the outer layer of the stem helping with resistance to pests and diseases.

A Calcium magnesium supplement is used to aid in the development of strong cell walls and root growth.

A bloom booster is another essential part of the nutrients such as this provides an extra boost of mono potassium phosphate, a main source of phosphorus, to assist with flower and fruit development.

Sweeteners are usually another part of your nutrient arsenal as well. This provides sugars and carbohydrates which feed microbes within the root zone (rhizosphere) as well as giving the plant necessary sugars, starches, and carbohydrates to aid in photosynthesis.

Plant tonics are another beneficial additive growers will use to accelerate plant growth and well-being by feeding the plants humic acids that assist with nutrient uptake. They can usually include extra goodies such as vitamin B1 and other natural compounds. Humic acid’s act as a natural chelater to help with uptake of micronutrients more efficiently.

Microbial Inoculants

Although not specifically nutrients, microbial inoculants such as mycorrhizae and beneficial bacteria, which will aid in the development of the overall root system. This allows for more root surface area for nutrients to be absorbed at a higher rate. This contributes to overall crop development and production. As the saying goes, “The bigger the roots, the bigger the Fruits.

There are many brands and varieties available in today’s market. Deciding what goals are necessary within your own personal grow or operation will determine which type of nutrients you will be using. Getting with a Grow Generation Grow Pro to determine which works best for you is always a great choice.

Root Health

When it pertains to plant cultivation, sometimes it’s more of an art form rather than a science. One concept behind plant growth that is an essential component to learn about growing is the knowledge related to root health. Some would argue the roots of a plant are the most important part of a plant and yet, is easily one of the most damaged parts of a plant if not maintained. Roots help the plants stay anchored to the ground as well as allow uptake of water and nutrients that are needed to help growth. Therefore, having good healthy root zone is essential and beneficial for plant quality and quantity. There are several factors that should be considered to maintain a healthy root zone at optimum condition.

Having a healthy root zone is determined by a number of factors such as root oxygenation, root competition, root temperature, salinity, pathogens, microbial relationships and more. Oxygenation of the root zone, either with an air stone in a deep water culture hydroponics system, or a loose medium such as perlite in soil, will allow root health to improve and dramatically increase the speed of growth. Deprivation of oxygen will cause the roots to suffocate and not complete the aerobic respiration process.

As for root competition, some scientific studies have discovered that plants tend to produce more mass when growing next to a neighboring plant versus a plant growing alone. In some cases, companion planting of cover crops like a clover, the root zone will explode with life. The cover crop will have nitrogen fixing bacteria in the root zone contributing to the uptake of nitrogen by nearby plants that share this root zone.

Root temperature strongly affects shoot growth. It tends to play a more important role than the surrounding air temperature of a plant. If a plant is exposed to less than 30 minutes of root zone heat, the crop can be affected in many negative ways. Therefore, ensuring that the root temp remains temperate is essential. Cool root zone in nutrient solutions actually hold more dissolved oxygen for better oxygenation. Cooling the roots has other positive effects that play into the production of plant growth hormones as well.

Soil salinity can also be a serious issue regarding root health. Areas where salinity is extremely high tend to cause the root cells to lose moisture and die.

Lastly, microbial relationships can influence plant health and growth significantly. Basically, specific micro-organisms can be attracted to a plant by secretions released by root systems. This secretion is called root exudates. These exudates consist of amino acids, sugars, fatty acids, carbohydrates and proteins. They act as signals that form a symbiosis with microbes such as beneficial bacteria and mycorrhizae.

Mycorrhizae is a fungi that creates a symbiosis, or mutual relationship, with the plant’s roots. The plant allows the fungus to take the minimal amount of nutrients it needs to grow. As a return favor to the plant, the fungus becomes an extension of the root system, assisting in an even faster rate of nutrient absorption and uptake. Root exudates can even sense attack by pathogenic microbes and release phytoalexins as defense mechanisms. These phytoalexins are antimicrobial and antioxidant in nature, offering added immunity to pests and diseases.

When it comes to plant growth, root physiology is an aspect of plants every grower must consider when creating and orchestrating a system, soil or hydroponics.