Proper light management is crucial for every greenhouse grower. Natural light intensity can fluctuate throughout the day and change seasonally. This makes it important to ensure that your plants are getting the light they need throughout the year. So how do you keep track of the amount of light your crop is receiving? One effective strategy is to manage your Daily Light Integral.

Daily light integral, referred to as DLI, is the amount of photosynthetically active radiation (PAR) received each day as a function of light intensity and duration. It is expressed in terms of moles of light per square meter per day, or mol/(m²·d). This metric is important to measure since the amount of light your plants get in a day relates directly to plant growth, development, yield, and crop quality.

Besides light intensity, there are several other factors that go into determining your DLI. Latitude, time of year, and length of day will all affect your DLI. Throughout the year, outdoor DLI ranges from 5 to 60 mol/(m²·d). However, in the greenhouse, values seldom exceed 25 mol/(m²·d) due to glazing material, structure shading, seasonality, cloud cover, day length, and other greenhouse obstructions.

Managing DLI is especially important for growers in northern latitudes where the majority of crops are propagated from December to March when naturally occurring outdoor DLI values may range between 5 to 30 mol/(m²·d). Inside the greenhouse these values can drop as much as 20% to 70%, with DLIs averaging as low as 1 to 5 mol/(m²·d)! Even during the spring and summer months DLI can vary widely depending on the weather and can often fail to meet ideal lighting conditions for your crops. Growers who monitor their DLI have the benefit of easily determining when to deploy lighting strategies such as supplemental lighting or retractable shade curtains.

Korczynski, Pamela C.; Logan, Joanne; Faust, James E. (2002-01-01). “Mapping Monthly Distribution of Daily Light Integrals across the Contiguous United States”. HortTechnology. 12 (1): 12–16.

Above is a DLI map of the United States developed by researchers from Clemson University (ref. below). The map shows estimated outdoor DLI by region for each month. To estimate the DLI inside your greenhouse, you can multiply the outdoor DLI from this map by your glazing transmittance rate.

For the most accurate results, there are also monitors that can be used to measure the DLI that your crops are receiving. We recommended a quantum light sensor connected to a data logger to record the instantaneous light intensity, which can then be used to calculate DLI. Knowing your specific ambient DLI (the amount of sunlight within your greenhouse) allows you to determine how much supplemental light is needed to meet your crops’ DLI targets.

Calculating your ambient or supplemental DLI is easy using the following equation:

Of course, here at LumiGrow we recommend some of our smart technology to help make your life easier. Take a look!

Resources:

Want to get in touch with LumiGrow? They can be reached via the following methods:

1. Website: https://www.lumigrow.com/
2. Phone: 800-514-0487
3. Email: info@lumigrow.com

Ever wonder how microbes eat? The core scientific team at Growcentia has conducted years of research to best understand how enzymes function to support plant growth. We’ve studied how enzymes produced by bacteria and fungi influence soil function and plant production in a range of ecosystems ranging from grasslands to the Arctic, and in a variety of agricultural systems.

Enzymes are the tools that soil microbes use to make nutrients available for microbial and plant uptake. Plants don’t have mouths, and they can only take up nutrients by absorbing them through their cell wall. Enzymes are critical components to support plant growth because most of the organic material in soils and soilless media are too big and insoluble for plants to take up. Therefore, nutrients must first be broken into smaller molecules that the plants can use. To accomplish this, microbes produce enzymes – specialized proteins that catalyze the breakdown of large molecules into smaller molecules – and release them into the environment to break down nutrients into smaller forms that plants can uptake!

Editor’s Note: Enzymes can perform many other functions too. They catalyze most of the reactions that occur in living organisms in a process known as metabolism.

Carbon is the currency of all life on Earth, and plants get their carbon from the CO₂ in the air. However, plants draw all other essential nutrients required for growth from the soil. Soil microbes produce the enzymes that cycle nitrogen, phosphorus and other nutrients to feed plants. Concurrently, plants feed the microbes using a variety of carbon-rich compounds that leak from plant roots, called exudates, as well as dead root cells. Microbes rely on their extracellular enzymes to break down different forms of carbon, which fuel their activity and growth, and enable them to cycle important macro and micro nutrients for both microbial and plant uptake.

Microbes tend to invest in producing enzymes to meet environmental nutritional needs. Depending on the relative availability of different elements, they focus on producing enzymes that release the nutrients that are most limiting. For example, to acquire phosphorus, microbes produce phosphatase enzymes. To acquire nitrogen, they produce enzymes like chitinases and proteases to break down nitrogen-rich organic compounds.

Beneficial bacteria support plant growth by acting like mini enzyme factories. By continuously producing enzymes, microbes ensure that nutrients are efficiently recycled and delivered to plants, and that waste products don’t accumulate in the soil and soilless media. For growers, it’s important to recognize that when enzyme-producing microbes are present, plants partner with them to efficiently cycle the nutrients in their environment. Additionally, beneficial bacteria help maintain the proper ratio of nutrients by shifting enzyme production to meet plant nutrient demands.

Using beneficial microbes will maximize plant nutrient uptake, development, quality and yield! In our research, we discovered that plant species influence microbial production of enzymes. For example, plants seem to influence microbes to produce nitrogen degrading enzymes, or phosphorus degrading enzymes so that plants can acquire the right amounts of each nutrient that they need to grow. Microbes help plants get the nutrients they need!

1. Wallenstein, M. D. and R. G. Burns. 2011. Ecology of extracellular enzyme activities and organic matter degradation in soil: A complex community-driven process. Methods of soil enzymology. SSSA Book Ser 9:35-56.
2. Bell, C. W., B. E. Fricks, J. D. Rocca, J. M. Steinweg, S. K. McMahon, and M. D. Wallenstein. 2013. High-throughput fluorometric measurement of potential soil extracellular enzyme activities. Journal of Visualized Experiments. doi 10:50961.
3. Bell, C., Y. Carrillo, C. M. Boot, J. D. Rocca, E. Pendall, and M. D. Wallenstein. 2014. Rhizosphere stoichiometry: are C: N: P ratios of plants, soils, and enzymes conserved at the plant species‐level? New Phytologist 201:505-517.

1. Arnosti, C., C. Bell, D. Moorhead, R. Sinsabaugh, A. Steen, M. Stromberger, M. Wallenstein, and M. Weintraub. 2014. Extracellular enzymes in terrestrial, freshwater, and marine environments: perspectives on system variability and common research needs. Biogeochemistry 117:5-21.
2. Bell, C., M. Stromberger, and M. Wallenstein. 2014. New insights into enzymes in the environment. Biogeochemistry 117:1-4.
3. Burns, R. G., J. L. DeForest, J. Marxsen, R. L. Sinsabaugh, M. E. Stromberger, M. D. Wallenstein, M. N. Weintraub, and A. Zoppini. 2013. Soil enzymes in a changing environment: current knowledge and future directions. Soil Biology and Biochemistry 58:216-234.
4. Nannipieri P, Kandeler E, and Ruggiero P. 2002. Enzyme activities and microbiological and biochemical processes in soil. Enzymes in the environment Marcel Dekker, New York:1-33.
5. Sinsabaugh RL, Carreiro MM, and Alvarez S. 2002. Enzyme and microbial dynamics of litter decomposition. Enzymes in the Environment, Activity, Ecology, and Applications Marcel Dekker, New York, Basel:249-265.
6. Sinsabaugh, R. L., C. L. Lauber, M. N. Weintraub, B. Ahmed, S. D. Allison, C. Crenshaw, A. R. Contosta, D. Cusack, S. Frey, and M. E. Gallo. 2008. Stoichiometry of soil enzyme activity at global scale. Ecology Letters 11:1252-1264.
7. Wallenstein, M. D. and M. N. Weintraub. 2008. Emerging tools for measuring and modeling the in situ activity of soil extracellular enzymes. Soil Biology and Biochemistry 40:2098-2106.
8. Wallenstein, M. D., M. L. Haddix, D. D. Lee, R. T. Conant, and E. A. Paul. 2011. A litter-slurry technique elucidates the key role of enzyme production and microbial dynamics in temperature sensitivity of organic matter decomposition. Soil Biology and Biochemistry.
9. Wallenstein, M. D., S. K. Mcmahon, and J. P. Schimel. 2009. Seasonal variation in enzyme activities and temperature sensitivities in Arctic tundra soils. Global Change Biology 15:1631-1639.
10. Wallenstein, M., S. D. Allison, J. Ernakovich, J. M. Steinweg, and R. Sinsabaugh. 2011. Controls on the temperature sensitivity of soil enzymes: a key driver of in situ enzyme activity rates. Soil Enzymology:245-258.

Resources:

Want to get in touch with Mammoth Microbes? They can be reached via the following methods:

1. Website: https://mammothmicrobes.com/
2. Email: info@growcentia.com
3. Phone: (970) 818-3321

We have known that light is responsible for driving plant growth via photosynthesis for many years; however, the influence of light on plant development has only become well understood in the last century. The color of light is not only an important variable for photosynthesis, but also acts as a packet of information to signal light mediated developmental responses in plants, such as: seed germination, stem elongation, and flowering. The term used to describe these responses in plants is photomorphogenesis. Plant morphology is extremely important in controlled environment agriculture where vertical or horizontal growing space may be limited. Depending on the plant architecture you desire, there may be other aspects of horticulture lighting systems to consider beyond providing a source of photosynthetic light.

Photosynthetically active radiation (400 – 700 nm) is mainly used for photosynthesis, however, plants can sense wavelengths ranging all the way from UV-C (260 nm) to far-red (730 nm) using separate photoreceptors that are not utilized for photosynthesis. These photoreceptors direct an adaptive response in plants under changing environmental conditions to regulate key stages of plant development which depend strongly on the spectrum of light, and in some cases timing, periodicity, and the overall exposure. The latter is usually called fluence, and is measured in micromoles of photons per square meter of surface. There are very low, low, and high fluence responses, with the corresponding sufficient light levels ranging from those of star light (for very low light levels) to direct sunlight (for high light levels). The purpose of this article is to describe photomorphogenic responses in plants.

VYPRx PLUS with PhysioSpec Greenhouse compared to a typical high pressure sodium (HPS) grow light.

There are long-day plants (which require short nights to flower), short-day plants (requiring long nights), and day-neutral plants which have no specific requirement for the photoperiod. This dependence on the photoperiod is referred to as photoperiodism. However, it is the length of the dark period (scotoperiod) that regulates flowering of photoperiodic plant species. In the absence of light, P_fr slowly converts to P_r, and as the scotoperiod increases, so does the relative amount of P_r. Long day plants (which have a short scotoperiod) will not flower if P_fr converts to P_r during the scotoperiod, while short day plants (which have a long scotoperiod) will only flower if P_fr converts to P_r during the scotoperiod. Photoperiodic phytochrome responses occur in the low fluence range (as low as 1 µmol/m²), so it can only take a short flash of R light to during a scotoperiod to revert P_r back to P_fr. For example, flowering of a long-day plant may be induced by night interruption, using a series of short flashes of red light with photon flux levels as low as a few µmoles/m²s. Conversely, short-day plants may be induced to flower by a single flash with pure FR light at the very beginning of the dark photoperiod, after turning off all other lights. This effectively adds a couple of hours to the dark period for the purpose of flowering, which can be used to extend the light period for growth and optimize plant yields as a result. Switching the above methods for plants with opposite photoperiod requirements would delay flowering, which may also be desired sometimes (e.g. to provide the best quality flowers on schedule for certain holidays).

A good energy-saving (and thus, cost-saving) strategy is to use one set of lights for growth and another for photoperiod control when necessary. Since phytochrome response is in the low fluence range, the number of fixtures needed for photoperiod control may be much smaller than that of fixtures needed for growth. In addition, the operating time needed for photoperiod control can be much shorter, such as only minutes at a time. Since FR light is only partially photosynthetically active, its use in horticulture lighting is often limited for reasons of energy efficiency.

VYPRx PLUS with PhysioSpec Greenhouse compared to a typical “purple” LED grow light.

Another important R and FR photomorphogenic response important to horticultural lighting systems is called the shade avoidance response. Far-red light is transmitted through leaf tissue more so than red light, which causes an enrichment of far-red light, relative to red light, for plants grown under canopies. When a low R:FR ratio is perceived by phytochrome pigments, a shade avoidance response is activated to elongate hypocotyls or stems in an attempt to out-compete neighboring plants. This is very important when it comes to the spectral light quality of horticultural lighting systems. Photoperiodic lights that provide a low R:FR ratio to promote flowing may also induce a shade avoidance response in plants, which may result in an undesirable growth habit, especially if a compact growth habit is preferred.

Resources:

Want to get in touch with Fluence? They can be reached via the following methods:

1. Website: https://fluence.science/
2. Email: info@fluencebioengineering.com
3. Phone: 512-212-4544

There’s a lot to concentrate on if you’re to keep your plants healthy and reap the best harvests: The right light, proper humidity, correct temperatures for their growth stage, preventing powdery mildew… and providing dissolved oxygen to your plants’ roots.

Water is made up of hydrogen and oxygen atoms bound together. However, there’s a different form of oxygen hanging out between those water molecules: Molecular oxygen (O₂). Molecular oxygen, also known as dissolved oxygen or DO, is used by plant roots for growth.

Editor’s Note: Water is an excellent solvent because it is a polar molecule.

Most water sources naturally contain some DO; the amount contained in outdoor bodies of water varies depending on pollution, water temperature, water aeration (moving streams contain more DO than still lakes) and other factors. Even ordinary tap water contains some DO (usually 5 to 7 parts per million, or PPM) at room temperature. In most grow rooms, you’ll be controlling the amount of DO in the water you use, usually ranging from about 7 to 10 PPM.

The plants in your grow room’s hydroponic system need dissolved oxygen (DO) in their water if they are to thrive and provide the best yields. Plant root systems use oxygen for aerobic respiration, and with a hydroponic system, most oxygen used in root uptake is in the nutrient solution. If plant roots don’t get enough oxygen, they become less permeable, take in less water, and can no longer absorb nutrients properly. Toxins also begin to build up. If oxygen deprivation continues, plants begin to “starve” from lack of nutrition. Roots begin to die, and plant growth is stunted. Ultimately, pathogens can take over and finish off the weakened plant.

Standard tap water usually contains other elements, like chlorine, which reduce the amount of oxygen tap water can hold. Water’s salinity is also a factor: The higher the salinity, the less soluble the oxygen, resulting in lower DO levels. Normal nutrients you add to the water do the same thing. Contaminants like bacteria will also reduce the amount of DO available to plant roots.

Editor’s Note: Think of the potential dissolution capacity of water as a limited resource. Salts, bacteria, and nutrients will all consume some of the dissolution capacity, leaving less room for water to dissolve.

For all of those reasons, many growers opt for reverse osmosis filtered water, with just enough nutrient solids added to meet plants’ nutritional needs. Dehumidifier water can also provide a “free” and endlessly renewable supply of water that may be preferable to reverse osmosis filtered water.

Temperature also affects how much DO water can hold. The lower the water temperature, the more oxygen it can hold; the higher the temperature, the less it will hold. Water that is fully oxygenated or 100% “saturated” with DO at the grow room temperatures optimal for plant growth will be in the ~7 to 10 PPM range.

Editor’s Note: Water is better at dissolving solids when it is warm, and better at dissolving gases (such as oxygen and carbon dioxide) when it’s cold. There is a tradeoff to be made with water temperature.

Resources:

Want to get in touch with Quest Hydro? They can be reached via the following methods:

1. Website: https://questhydro.com/
2. Email: info@questhydro.com
3. Phone: 877-420-1330

Mother plants, sometimes called stock plants, are used for plant cloning. Cuttings are taken from a mother plant to produce a plant with identical genes to the mother. Mother plants and clones are great for growers because some strains have desirable characteristics they want to replicate. Mother plants also save money on seeds.

Once a cutting is taken from the mother plant it needs time to develop roots. After all, a cutting is essentially a rootless plant. Without any roots, cuttings rely on water and carbohydrates already stored in their stems and leaves to help fuel new root growth. That’s where nutrients specific to mother plants can help.

Related Article: We discuss why cuttings are placed into cloning domes in our article on VPD for Cannabis Cultivation!

Mother plants have different nutritional requirements than more traditional plants in the vegetative state. Where a plant in veg needs nitrogen for growth, a mother plant may not produce healthy clones if it’s fed a nitrogen-rich nutrient. Too much nitrogen in a mother plant’s diet results in soft tissues with low carbohydrate levels. While the excess nitrogen will result in quick plant growth, it does not help provide the fuel that clones need to produce healthy, new root growth. Clones need sturdy, carbohydrate-rich fuel.

When a plant is fed nitrogen, it will use up to 25 to 30% of its energy to convert those nitrates into a form of nitrogen that plants can use for vegetative growth. Using the plant’s energy for growth results in fewer sugars, or carbohydrates, in the stems and leaves. This reduces the potential fuel for the clones to create new root growth, leaving them prone to failure.

Mother plants fed a diet specific to them will produce healthy clones. A good mother plant nutrient should always be formulated to improve the plant’s health, and not strictly focused on growth like nitrogen-rich nutrients are. Areas that mother plant nutrients should focus are things such as:

Clones taken from plants with thin cell walls tend to be more fragile and prone to wilting and infections. A fertilizer created for mother plants should help to strengthen cell walls, resulting in stronger clones.

Calcium is important for mother plants as it helps to bind cell walls together. A mother plant that is calcium-rich has stronger cells, and has improved water and nutrients uptake. In turn, this allows more carbohydrates to be stored in the leaves and stems.

Once a cutting is taken, both the mother plant and the cutting are under stress. A good mother plant fertilizer will provide the nutrients needed for stronger stress tolerance in the mother plant and the cutting.

One of the biggest indicators that a mother plant nutrient is formulated to focus on these areas is the inclusion of bio-organics. Bio-organics can improve calcium uptake and increase stress and disease resistance.

Editor’s Note: There are many methods to reduce stress in plants, including VPD control. Check out our article on Vapor Pressure Deficit.

Overall, a healthy mother plant needs a specific diet to provide fuel that the cuttings need to successfully take root. A good mother plant fertilizer will provide lower nitrogen levels than a typical fertilizer, so the plant can focus on storing energy, instead of converting the excess nitrogen into new growth. A grower that wants to continue the genetics of their favorite strain will benefit from providing the mother plant with nutrients geared towards producing healthy cuttings.

Resources:

>Want to get in touch with Hydrodynamics International? They can be reached via the following methods:

1. Website: https://www.hydrodynamicsintl.com/
2. Phone: 517-887-2007
3. Email: info@hydrodynamicsintl.com

Hi Guys, Dr. NPK here. I warned you that I was going to have my pun game on point. Anyway, time to finish up our conversation about the micronutrients: specifically, what each element does, and what signs indicate that there is a deficiency in the aforementioned element. (Check out Part 1 here) As a quick refresher, here is the list of micronutrients used in cannabis hydroponics:

Manganese (Mn)	Boron (B)
Copper (Cu)	Zinc (Zn)
Molybdenum (Mo)	Cobalt (Co)

Some say iron as well. I classify it as a secondary nutrient, separate post on iron coming up soon.

Real quickly, just want to make sure you understand, Manganese (Mn) is different than Magnesium (Mg). Despite being different, both manganese (a micronutrient) and magnesium (a secondary nutrient) are both involved in photosynthesis. Magnesium is incorporated into the chlorophyll molecule, whereas manganese helps with the photosynthetic process. Manganese is essential in starch development (aka carbohydrate); in chemistry, Manganese is an excellent oxidizer/reducer, so it can move electrons around efficiently. The ability to move electrons around helps it in the electron transport chain in the plant. (Mousavi et al. Aust. J. Basic & Appl. Sci. 2011, 5, 1799–1803). Manganese is also an important part in the activation of a variety of enzymes. The right amount of manganese means higher yields because photosynthesis efficiency improves.

Symptoms of manganese deficiencies are like magnesium deficiencies, because it affects the photosynthetic process, primarily yellowing the leaves (interveinal chlorosis). Manganese is less mobile than magnesium, so young leaves are affected more than older ones. One major reason that your plants may be short on manganese may be due to higher pH (Basic water interferes with manganese uptake), or the presence of a significant amount of organic matter (which outcompetes the manganese molecules in uptake). Remember to use chelated manganese products!

I like copper the most of the micronutrients. My main reason for liking this micro so much is due to its benefits. Copper is a vital micro for setting up your plants for great lateral growth, as well as excellent disease resistance (notice how many fungicides contain copper?). Lignin biosynthesis needs appropriate levels of copper; lignin is a special macropolymer (say that ten times fast) that is used to support cell wall strength (Alaru et al. Field Crops Research 2011, 124, 332–339). Copper is also important in other enzymatic processes (it is a great electron transport agent, like manganese), but I really think the take-home message here is that copper means enhanced lateral growth.

Symptoms of copper deficiency are difficult to diagnose, as they are not quite as clear as other micronutrient deficiencies, but leaf wilting and stunted growth are good signs that you’re short on copper. Be careful! Copper toxicity is a real thing, so don’t go crazy and overcorrect with copper. Check to make sure your copper source is a chelated copper. I haven’t had much success with copper sulfate, it tends to get tied up by other ions in solution.

Yes, ‘tis true, 0.0008% is a calculated number. Molybdenum is a nasty heavy metal that can affect human health in high concentrations. Most plant-friendly molybdenum sources are supplied as the “molybdate” (IE “sodium molybdate”). The molybdate form of molybdenum is just negatively charged (think of like magnesium sulfate, where the magnesium is positively charged and the sulfate is negatively charged -- time to bust out your chemistry textbooks!). Molybdenum is a funny micro because it is more of a “support element.” Molybdenum is a vital element in the formation of the enzymes nitrate reductase and sulfite oxidase (Kaiser et al. Annals of Botany 2005, 96, 745–754). The key one here is “nitrate reductase” – molybdenum is required to support nitrogen processing in your plant. Appropriate molybdenum means nitrogen absorption which means green plants and growth!

Molybdenum deficiencies are very rare (a little goes a long way!), but the main reason is due to nutrient lockout resulting from low pH. The easiest way to tell if you have a molybdenum problem is if your plant is exhibiting what seems like nitrogen deficiencies but you’re sure your plants are getting enough nitrogen. Without molybdenum, that nitrogen can’t be processed.

Boron has a special place in my heart: my Ph.D. dissertation was centered around this element. Boron is extremely important in plant nutrition, and is one of the most common micronutrient deficiencies in crop nutrition today (Shorrocks, V. M. Plant and Soil 1997, 193, 121–148).

Thankfully, boron deficiency is rare in cannabis growing. Boron is one of the few micros that is not supplied in a chelated form. One of boron’s most important roles is in sugar translocation: it’s all great that photosynthesis creates energy and sugar, but just like any manufacturing location, product must be moved off the floor! Boron is one of the elements that helps facilitate this (Mitchell et al. Science 1960, 132, 898–899). Boron means more efficient photosynthesis, which means better yields!

Boron deficiencies tend to coincide with the symptoms of other macro deficiencies; leaf spotting and weak stems (boron is associated to the cell wall). Foliar sprays of boron are one option, but make sure you have the proper pH and ensure the nutes you are working with contain boron.

Side note: I know that some people use borax (sodium borate), but I would encourage you not to use this material because sodium is detrimental to cannabis in high quantities.

Cobalt is up there with molybdenum in terms of being small players in the micronutrient realm. Despite being needed in small quantities, cobalt plays an important role in stem growth and elongation (Grover et al. Plant. Physiol. 1976, 57, 886–889). Cobalt is also an important support nutrient for nitrogen and potassium uptake. Cobalt therefore means better stem elongation and better yields!

Cobalt deficiencies, as previously mentioned, are rare, especially because cobalt doesn’t need to be chelated, so it’s hard to lock it out. Symptoms of this rare deficiency have to do with stem elongation and growth – if you are experiencing improper spacing and growth, cobalt may be the culprit. However, I’d check macros and secondaries first before pointing the finger at cobalt.

We have arrived at our last micronutrient, zinc! Zinc is an important micronutrient from a growth perspective. In small quantities it’s needed to ensure appropriate growth and prevent chlorosis. Like many of the other micronutrients, zinc should be in a chelated form (Zn EDTA for example). Zinc means improved yield and healthy intermodal spacing.

Being an immobile element, zinc deficiencies tend to manifest in the newer/younger leaves. These leaves will not only exhibit chlorosis, but also will be wilted and look generally unhealthy. Zinc, like cobalt and molybdenum, is required in small amounts. Zinc toxicity is a real possibility!

Dude, that was a lot of elements to discuss. The take-home message here is this: keep your pH at an appropriate level, and buy a micronutrient product that can really supply all the micros that you need. Elite Base Nutrient A and B provide all the micros that you need to help avoid the micronutrient deficiencies listed. Consolidation is always a nice thing!

Resources:

Want to get in touch with Elite Garden Wholesale? They can be reached via the following methods:

1. Website: https://www.elitegardenwholesale.com/
2. Email: info@elitegardenwholesale.com

More and more cannabis enthusiasts are educating themselves on what fantastic finished product looks and smells like. The true indicator of superior cannabis is in the cure. Cannabis connoisseurs know this.

With an increase of legal cultivators flooding into new markets, these growers must produce exceptional product to appeal to the most discerning tastes.

The cannabis world is learning quickly that the true secret to fuller, more potent, and more enjoyable buds is all in the cure. As legal cannabis cultivation has expanded, curing has advanced to keep up with demand.

The curing process begins even before the harvest. For the cultivator who harvests product with care, a solid humidity control strategy is the way to go. Throughout the cultivation process, humidity in the air must be kept as consistent as possible to produce the highest quality flowers.

As a cannabis grower, you can control the environment if you’re adaptable. Choose the best grow operation based on your climate (and local laws, of course), such as:

1. Outdoor
2. Greenhouse
3. Hydroponic

Many growers prefer a hydroponic system, which lets you easily adjust the humidity level indoors. Other cultivators prefer a greenhouse setting where natural light can shine in while moisture levels can be contained. Either way, it’s a lot of work to regulate an internal environment every day. The best cultivators strive for perfection in every possible area of grow.

It doesn’t matter if it’s grown indoors or outdoors; the flavors and aromas of professionally grown cannabis exist thanks to modern humidity control. The finished product in your jar has been through a long and painstaking journey! Growing cannabis is more than simply planting seeds and waiting for them to grow.

Several vital steps don’t take place until after the harvest, such as:

1. Cutting and hanging plant limbs to dry
2. Trimming old growth off of the flowers
3. Curing, which dries and prepares the flower for packaging, retail and eventually consumption

Perhaps the most important and overlooked part of cultivation is knowing when to harvest the plants. Here’s where things get tricky for cultivators: Harvesting too early could negatively affect the potency of your finished flower; letting the flowers sit too long on the plant could cause them to prematurely dry out. Know the growing cycle by heart -- it’s the sign of a truly skilled grower.

After harvest, cannabis flower should be dried for three to seven days in a humidity-controlled environment. You want the moisture to evaporate slowly, so the buds don’t become too dry. After this initial drying process, flower should always be cured in special airtight containers (which we recommend including Boveda packs with).

Grain and produce growers go to great lengths to keep their harvests fresh long after they reach their final destination. The same should be true for high-grade cannabis flowers. Odds are, freshly cured cannabis isn’t consumed right away. En route to a retail space, buds must be properly stored until they are purchased. The loss of flavors and aromas, quality and potency, and even the valuable weight of cannabis buds are most frequent in post-harvest storage.

The easiest way to get the product from Point A to Point B isn’t necessarily the best way.

1. Product should never be carelessly stored in plastic bags or jars without proper humidity control.
2. To maintain freshness, prevent moisture damage, and eliminate over drying, store cannabis in containers that have dark, airtight closures (which we again recommend Boveda packs for).

No matter how long it’s been since the harvest, a solid cure will ensure a quality product that leaves your consumer wanting more.

Resources:

Want to get in touch with Boveda? They can be reached via the following methods:

1. Website: https://bovedainc.com/
2. Email: dan.cleveland@bovedainc.com

One of the most crucial factors influencing cannabis growth is temperature. Temperature plays a vital role in a plant’s growth processes such as photosynthesis and transpiration, which are responsible for the plant's physical development and nutrient uptake. Temperature is also crucial in the production of a cannabis plant's resins and terpenes. This impacts the quantity, quality, and composition of the final product. Growers in closed growing spaces need to maintain temperatures within optimal ranges for ideal growth.

Generally, optimal temperatures for cannabis growth are approximately 25-30°C (77-86°F) during daytime hours. Ideal night time temperatures are around 17-18°C (63-64.5°F). A temperature difference (DIF) between day and night is important in order to stimulate proper growth.

Temperatures that are too high can elevate susceptibility to many problems, including root rot, spider mites, nutrient burning, and wilting. High temperatures combined with high humidities can result in outbursts of fungal diseases like powdery mildew. Heat damage can also cause damage to leaves and buds, resulting in a yield reduction.

Editor’s Note: Leaf temperatures greatly affect the ability of fungal pathogens to grow. The specific temperatures that are optimal to prevent pathogenesis depend on the pathogen in question. In mammals, it is believed that our body temperature of 98-99 Fahrenheit is ideal for preventing most fungal infections.

If temperatures are too low, plant processes are significantly slowed and will result in an underdeveloped, smaller plant, or even result in plant death. Colder temperatures also make plants more susceptible to certain detrimental plant diseases.

Several factors impact indoor temperatures and should be taken into consideration by the grower. These include:

1. Outside air temperature: The temperature of the air outside of a growing facility impacts the amount of heat being absorbed by the structure and radiated inside. Heat energy will always move from hotter to colder conditions, so the difference between outside and inside temperatures will cause heat to be lost or gained in the growing facility.
2. Insulation: Heat exchange through the walls of a structure vary depending on the amount of insulation the walls are equipped with. This directly impacts the amount of energy needed to maintain target temperatures within the growing facility. Different materials have different insulation capacities: polycarbonate can retain more heat than glass, and glass can retain more heat than polyethylene. Insulation can be improved with the addition of thermal screens indoors. It is also improved when a facility is sealed off. Open doors, windows, holes, or leaks will lower the insulation capacity of facilities and should be checked regularly.
3. Soil: Heat energy entering the facility also gets absorbed into the soil. Throughout the day, soil heats up, and, at night, the heat is released into the growing facility.
4. Machinery: The energy utilized by any machinery within the greenhouse remains inside of the greenhouse. According to the law of conservation of energy, any electricity not used by the machine gets converted into heat energy. In most cases, the most influential addition of energy often comes from HID grow lights. The type of lamp and amount of heat it gives off, its distance from plants, and its dimming settings can all impact temperature in the grow space. LED lights give off significantly less heat and are more energy-efficient than their hotter counterparts such as HPS lamps.

Growers have a number of tools they can use to control temperatures in enclosed growing spaces:

1. Ventilation: Ventilation brings air from the outside environment into the grow space and moves the inside air outside. This can be done by opening and closing the growing facility's doors and windows, or with fans pushing air in and out of the structure and circulating air within. Outside air temperatures will impact the temperature change that ventilation will affect; air will move naturally based on the temperature gradient.
2. Cooling systems: A variety of options are available for cooling greenhouse spaces. Evaporative cooling systems utilize the physical properties of water changing phases from liquid to gas to cool the environment. Examples include misting and wet pad-and-fan systems. Air conditioning is another option, where air is cooled as it passes over refrigerated coils that have been chilled.
3. Heating systems: Heating systems are largely divided into two types: hot water or hot air. In heated water systems, a boiler heats water that runs into pipes or tubes distributed throughout the growing space and heat is given off via conduction or convection. Hot air systems heat the air, typically utilizing a gas burner. The hot air is then distributed to the structure by fan via perforated ducts. Since hot air rises, the location of the pipes or ducts influences the heat distribution and air circulation.
4. HVAC systems: These are integrated systems that can be used to both cool and heat enclosed spaces. They involve a series of components which heat, cool, disperse, and ventilate indoor air. They require a substantial amount of infrastructure and electricity, but are more versatile in their abilities.

Many components play a role in temperature regulation around the growing facility. Growers must learn how best to integrate all of these elements in their facility in order to ensure optimal growth and quality. In future topics, we’ll dive deeper into the different types of heating and cooling options that a grower can choose from to create the best conditions.

Resources:

Want to get in touch with DryGair? They can be reached via the following methods:

1. Website: https://www.drygair.com
2. Phone: +972-9-7730980
3. Email: info@drygair.com