Tag Archives: contaminate

Tips for Finding the Perfect Cannabis Packaging Partner for Your Business

By Danielle Antos
1 Comment

Whether your cannabis business is a start-up in its infancy, or established with a loyal customer following, the product packaging you use is essential to building and maintaining your brand. The packaging is the first thing a potential customer sees, and it creates that critical first impression. While the primary function is to contain, protect, and market your products, your packaging is a reflection of your company to the customer. In many ways, the package is the product. Partnering with a quality plastic packaging manufacturer for your cannabis products will increase your success.

Bottles made of high-density polyethylene (HDPE), low density polyethylene (LDPE), polypropylene (PP), and polyethylene terephthalate (PET) have become widely-accepted packaging options within the cannabis industry. There are many plastic bottle manufacturers, but how do you find the right one? In short, seek a manufacturer who makes quality products that are unlikely to present downstream problems for your company, provides services and options that align with things you feel are important, and wants to build a long-term relationship with you so both of your businesses grow faster through strategic partnership.

What to Look for in a Plastic Bottle Manufacturer

Excess Bottom Flash creates a poor printing surface.

As you search for a packaging partner for your cannabis business, here are a few key things to look for:

Bottles That Visually Support Your Brand

It’s essential to partner with a manufacturer who understands the importance of defect-free plastic bottles. Does everything about your packaging convey a sense of trust for your customers? Defects in plastic bottles typically occur during the manufacturing process.

Excessive Side Taper results in uneven, wrinkled labels.

For instance, excessive side taper on the bottles can result in uneven, wrinkled labels that are hard to read and make your product look unprofessional. If flashing on the bottle bottom is not removed, it creates a poor printing surface and results in a poor brand impression.

Partnering with a manufacturer who understands that plastic bottle defects diminish brand presence and who continually strives to remove defect-producing problems out of their manufacturing process is of utmost importance. This avoids many downstream quality problems and helps to keep the focus on growth and off of damage control.

Bottles That Minimize Risk and Waste

Product recalls or safety concerns can be a result of cloudy bottles or material trapped in the resin that makes the plastic packaging look dirty or contaminated. These situations can erode consumer confidence in your brand or expose the customer to risk.

Foreign material trapped in the resin results in reduced customer confidence.

Sub-par plastic bottles can lead to inefficiencies on your filling lines, lost production time, and product that cannot be sold. These situations lead to reduced profitability and negatively impact your bottom line. It’s never good when filled packaging or product has to be thrown away because problems are identified on the filling line.

Uneven Sealing Surface results in poor closure seal and increased risk of product spoilage or contamination.

Worse yet is when your product reaches the point of sale and the problems are identified at the dispensary or by a consumer. For example, over time, an improper seal between the plastic bottle and cap can cause flower to be excessively dry. In turn, when this flower is dispensed to the consumer it can lead to overfilling to make up for weight loss. And some consumers just don’t like their flower to be too dry, resulting in lost sales. Does the defective product get shipped back or trashed at the point of sale location? In either case, this results in the dilemma of wasted product that can’t be used and extra costs that eat into your profitability. 

Closures That Work With The Bottle

The closures for the bottles are also an important part of your cannabis packaging. Can your packaging partner manufacture and supply plastic closures that assure complete functionality to protect your product? Closures produced by the same manufacturer as the bottles ensures that the closure and bottle function correctly together. A one-stop-shop approach will save you time and money.

The cannabis industry is growing quickly and faces many complex regulatory challenges, including regulations for child-resistant packaging. Many states have their own unique cannabis packaging requirements which must be strictly adhered to. Are their bottle and closure pairings compliant with current regulations and those that are under legislation for the future? 

Customization for Your Brand

Can the cannabis packaging manufacturer customize their products to your exact design and specifications? Your product is unique, and your packaging should reflect that. Make sure your brand stands out with the exact image you want to project. There should be “depth” in your supplier: can they do more than just sell you packaging that already exists?

A Safe Resin Source

Another important aspect of safety is country of origin. Plastic bottles and closures manufactured overseas may have impurities in the resin or colorant that could leach or bleed into your products. They may not have documentation of origin or comply with FDA regulations. Your plastic packaging partner should be able to provide this documentation so you can rest assured that your bottles are manufactured under strict guidelines for the safety of your consumers and that your product won’t be affected.

Commitment to Sustainability

To many consumers, packaging made from recycled materials is important. Does your packaging supplier have a strong commitment to environmental sustainability? There is strong market support for carbon-friendly alternatives. Progressive plastic packaging manufacturers are actively working to provide alternatives to plastics made from fossil fuels and instead, using resins produced from renewable resources (i.e. sugarcane). By partnering with a supplier that provides alternative and recycled materials, you enhance your brand by appealing to a growing segment of environmentally concerned consumers.the best cannabis packaging suppliers understand that consistency in the manufacturing process is essential.

Scalable Growth

As your business grows, can your packaging partner grow with you? It’s important that they are able to keep up with the demand for your product and that their supply chain can match your manufacturing needs. As you add to your product line, are they capable of continuing to offer new and innovative packaging? A manufacturer that has a strong business model for growth will benefit you now and for the future.

A Real Cannabis Packaging Partner

Your cannabis business should develop a true partnership with your packaging supplier. They should invest in your success and care about your business. Businesses depend on one another for continued growth – look for a knowledgeable partner that is responsive, courteous and dependable now and for years to come. The best suppliers realize that there is more to a relationship than just the financial transaction of buying packaging.

Additionally, the best cannabis packaging suppliers understand that consistency in the manufacturing process is essential. Using virtually perfect bottles time after time not only reduces waste but helps build consumers’ trust in your brand. Consistency saves you three precious commodities – time, hassle and money.

Remember, a brand consists of more than just a logo and company name. It identifies who you are, what your company stands for and the integrity of your product. Quality cannabis packaging will reinforce your company standards and attract consumers to your product – consistently defining you as a quality provider with integrity in the marketplace. Improving your bottom line and meeting your company’s financial goals is at stake. Is your cannabis packaging partner going to help you grow?

Food processing and sanitation

Sanitation Starting Points: More Than Sweeping the Floors and Wiping Down the Table

By Ellice Ogle
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Food processing and sanitation

Sanitation is not just sweeping the floors and wiping down the table – sanitation has a wide-ranging function in a cannabis food manufacturing facility. For example, sanitation covers the employees (and unwanted pests), food-contact equipment (and non-food-contact equipment), trash disposal (including sewage), and more. Ultimately, sanitation systems maintain a clean environment to prevent foodborne illness from affecting human health. Fortunately, there are resources and tools to ease into establishing a robust sanitation program.

Overall, the main goal of sanitation is to produce safe food, to keep consumers healthy and safe from foodborne illness. With the cannabis industry growing and gaining legalization, cannabis reaches a larger, wider audience. This population includes consumers most vulnerable to foodborne illness such as people with immunocompromised systems, the elderly, the pregnant, or the young. These consumers, and all consumers, need and deserve safe cannabis products every experience.

FDAlogoTo produce safe food, food manufacturing facilities in the United States must at least follow the Food and Drug Administration (FDA)’s Code of Federal Regulations Title 21 Chapter I Subchapter B Part 117, current good manufacturing practice, hazard analysis, and risk-based preventive controls for human food. Although cannabis is currently not federally regulated, these regulations are still relevant for a cannabis food manufacturing facility since the same basic principles still apply. Also, these regulations are a good resource to simplify a comprehensive sanitation program into more manageable components, between sanitary operations and sanitary facilities. With more manageable components, the transition is smoother to then identify the appropriate tools that will achieve a thorough sanitation program.

Sanitary operations

1) General maintenance of the facilities: The buildings and fixtures of the food manufacturing facility cover a lot of ground – hiring a maintenance team will divide the responsibility, ensuring the entire facility can be maintained in a clean and sanitary condition. Furthermore, a team can build out a tool like a preventative maintenance program to restrict issues from ever becoming issues.

Figure 1: Dirty Cloth Towel in Dirty “Sanitizer” Solution
Dirty Cloth Towel in Dirty “Sanitizer” Solution (an example of what NOT to do)

2) Control of the chemicals used for cleaning and sanitizing: Not all chemicals are equal – select the appropriate cleaning and sanitizing chemicals from reputable suppliers. Obtain the right knowledge and training on proper use, storage, and proper protective equipment (PPE). This ensures the safe and effective application of the chemicals in minimizing the risk of foodborne illness.

3) Pest control: Understand the environment within the facility and outside the facility. This will aid in identifying the most common or likely pests, in order to focus the pest control efforts. Keep in mind that internal pest management programs can be just as successful as hiring external pest control services.

4) Procedures for sanitation of both food-contact and non-food-contact surfaces: Developing sanitation standard operating procedures (SSOPs) provides guidance to employees on appropriate cleaning and sanitizing practices, to balance effective and efficient operations. A master sanitation schedule can control the frequency of indicated sanitation procedures.

5) Storage and handling of cleaned portable equipment and utensils: Cross contamination in storage can be minimized with tools such as controlled traffic flow, signage, training, color coding, and more.

Sanitary facilities

6) Water supply, plumbing, and sewage disposal: Routine inspections of plumbing, floor drainage, and sewage systems prevent unintended water flow and damage.

7) Toilet facilities: Clearly defining standards for the toilet facilities and setting accountability to everyone who uses them will ensure that the toilet facilities are not a source of contamination for the food products.

Food processing and sanitation
PPE for all employees at every stage of processing is essential

8) Hand-washing facilities: Good manufacturing practices (GMPs) include proper hand washing and proper hand washing starts with suitable hand-washing facilities. For example, frequent checks on running water, hand soap, and single use towels ensure that all hands are clean and ready to produce safe food.

9) Trash disposal: While trash can be a source of cross contamination, trash can also attract and harbor pests. Scheduling regular trash disposal and controlling traffic flow of waste are two ways to minimize the risk of cross contamination from trash.

Bonus

Even after meeting these requirements, sanitation programs can be more sophisticated. An example is to institute an environmental monitoring program to verify and validate that the sanitation program is effective. Another example is in identifying and measuring key performance indicators (KPIs) within the sanitation program that can improve not just the sanitation processes, but the operations as a whole. Principally, sanitation is cleanliness on the most basic level, but waste management can encompass sanitation and grow into a larger discussion on sustainability. All in all, sanitation programs must reshape and evolve alongside the company growth.

Sanitation is interwoven throughout the food manufacturing process; sanitation is not a single task to be carried out by a sole individual. As such, it is beneficial to incorporate sanitation practices into cannabis food manufacturing processes from the beginning. Protect your brand from product rework or recalls and, most importantly, protect your consumers from foodborne illness, by practicing proper sanitation.

autoclave

10 Treatment Methods to Reduce Mold in Cannabis

By Ketch DeGabrielle
6 Comments
autoclave

As the operations manager at Los Sueños Farms, the largest outdoor cannabis farm in the country, I was tasked with the challenge of finding a yeast and mold remediation treatment method that would ensure safe and healthy cannabis for all of our customers while complying with stringent regulations.

While outdoor cannabis is not inherently moldy, outdoor farms are vulnerable to changing weather conditions. Wind transports spores, which can cause mold. Each spore is a colony forming unit if plated at a lab, even if not germinated in the final product. In other words, perfectly good cannabis can easily fail microbial testing with the presence of benign spores.

Fun Fact: one square centimeter of mold can produce over 2,065,000,000 spores.

If all of those landed on cannabis it would be enough to cause over 450 pounds of cannabis to fail testing, even if those spores remained ungerminated.

Photo credit: Steep Hill- a petri dish of mold growth from tested cannabis

It should also be known that almost every food item purchased in a store goes through some type of remediation method to be considered safe for sale. Cannabis is finally becoming a legitimized industry and we will see regulations that make cannabis production look more like food production each year.

Regulations in Colorado (as well as Nevada and Canada) require cannabis to have a total yeast and mold count (TYMC) of ≤ 10,000 colony forming units per gram. We needed a TYMC treatment method that was safe, reliable, efficient and suitable for a large-scale operation. Our main problem was the presence of fungal spores, not living, growing mold.

Below is a short list of the pros and cons of each treatment method I compiled after two years of research:

Autoclave: This is the same technology used to sterilize tattoo needles and medical equipment. Autoclave uses heat and pressure to kill living things. While extremely effective, readily available and fiscally reasonable, this method is time-consuming and cannot treat large batches. It also utilizes moisture, which increases mold risk. The final product may experience decarboxylation and a change in color, taste and smell.

Dry Heat: Placing cannabis in dry heat is a very inexpensive method that is effective at reducing mold and yeast. However, it totally ruins product unless you plan to extract it.

autoclave
An autoclave
Image: Tom Beatty, Flickr

Gamma Ray Radiation: By applying gamma ray radiation, microbial growth is reduced in plants without affecting potency. This is a very effective, fast and scalable method that doesn’t cause terpene loss or decarboxylation. However, it uses ionizing radiation that can create new chemical compounds not present before, some of which can be cancer-causing. The Department of Homeland Security will never allow U.S. cannabis farmers to use this method, as it relies on a radioactive isotope to create the gamma rays.

Gas Treatment: (Ozone, Propylene Oxide, Ethylene Oxide, Sulfur Dioxide) Treatment with gas is inexpensive, readily available and treats the entire product. Gas treatment is time consuming and must be handled carefully, as all of these gases are toxic to humans. Ozone is challenging to scale while PPO, EO and SO2 are very scalable. Gases require special facilities to apply and it’s important to note that gases such as PPO and EO are carcinogenic. These methods introduce chemicals to cannabis and can affect the end product by reducing terpenes, aroma and flavor.

Hydrogen Peroxide: Spraying cannabis plants with a hydrogen peroxide mixture can reduce yeast and mold. However, moisture is increased, which can cause otherwise benign spores to germinate. This method only treats the surface level of the plant and is not an effective remediation treatment. It also causes extreme oxidation, burning the cannabis and removing terpenes.

Microwave: This method is readily available for small-scale use and is non-chemical based and non-ionizing. However, it causes uneven heating, burning product, which is damaging to terpenes and greatly reduces quality. This method can also result in a loss of moisture. Microwave treatment is difficult to scale and is not optimal for large cultivators.

Radio Frequency: This method is organic, non-toxic, non-ionizing and non-chemical based. It is also scalable and effective; treatment time is very fast and it treats the entire product at once. There is no decarboxylation or potency loss with radio frequency treatment. Minimal moisture loss and terpene loss may result. This method has been proven by a decade of use in the food industry and will probably become the standard in large-scale treatment facilities.

Steam Treatment: Water vapor treatment is effective in other industries, scalable, organic and readily available. This method wets cannabis, introducing further mold risk, and only treats the product surface. It also uses heat, which can cause decarboxylation, and takes a long time to implement. This is not an effective method to reduce TYMC in cannabis, even though it works very well for other agricultural products

extraction equipment
Extraction can be an effective form of remediating contaminated cannabis

Extraction: Using supercritical gas such as butane, heptane, carbon dioxide or hexane in the cannabis extraction process is the only method of remediation approved by the Colorado Marijuana Enforcement Division and is guaranteed to kill almost everything. It’s also readily available and easy to access. However, this time-consuming method will change your final product into a concentrate instead of flower and usually constitutes a high profit loss.

UV Light: This is an inexpensive and readily available method that is limited in efficacy. UV light is only effective on certain organisms and does not work well for killing mold spores. It also only kills what the light is touching, unless ozone is captured from photolysis of oxygen near the UV lamp. It is time consuming and very difficult to scale.

After exhaustively testing and researching all treatment methods, we settled on radio frequency treatment as the best option. APEX, a radio frequency treatment machine created by Ziel, allowed us to treat 100 pounds of cannabis in an hour – a critical factor when harvesting 36,000 plants during the October harvest.

photo of outdoor grow operation

How to Reduce Mold & Contaminants in Indoor, Greenhouse and Outdoor Grows

By Ketch DeGabrielle
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photo of outdoor grow operation

Controlling your grow environment doesn’t start when you germinate your first seeds, it starts before you build your grow. There are steps you can take that will have a significant impact on mold growth and contamination, and these will vary based on the grow environment you choose.

Below is a roadmap to where each grow environment stands in terms of mold and contamination risk, and simple steps you can take to mitigate these factors.

Outdoor

The benefits of an outdoor grow are significant – using natural sunlight to grow plants is both inexpensive and environmentally sound. However, it allows the least amount of control and makes plants susceptible to weather conditions and outdoor contaminants including dust, wind, rain and insects. Depending on humidity and precipitation levels, mold can be a big issue as well.

Outdoor growing has obvious benefits, such as natural sunlight, but may also require extra steps to prevent contamination

When selecting an outdoor area for a cannabis farm, there are two important factors to consider: location and neighboring farmland. Geographical environments and sub-climates vary and once you have purchased land, you are committed, so be sure to consider these factors prior to purchase.

While arid desert climates have abundant sunlight and long growing seasons, flat, dry lands are subject to dust-storms, flash floods and exceedingly high winds that can damage crops. Conversely, more protected areas often have high humidity and rainfall late in the season, which can create huge issues with bud rot and mold. Neighboring farms also have an impact on your grow, so be sure to find out what they cultivate, what they spray, their harvest schedule and how they run their operation. Large farming equipment kicks up a lot of contaminant-laden dust and can damage crops by displacing insects to your farm if they harvest before you. Pesticide drift is also a major issue as even tiny amounts from a neighbor’s farm can cause your crops to fail testing, depending on what state you are in.

With outdoor grow environments always at the mercy of Mother Nature, any cultivator is wise to control contamination potential on the ground. Cover soil and protect your crop by planting cover crops and laying plastic mulch on as much ground as reasonable. In many cases it makes sense to irrigate uncultivated parts of your farm just to keep dust down.

Greenhouse

Greenhouses are the future of cannabis cultivation. They allow growers to capture the full spectrum and power of the sun while lessening environmental impact and operating expenses, while still being able to precisely control the environment to grow great cannabis. With recent advancements in greenhouse technology such as automated control systems, positive pressure, geothermal heating or cooling and LED supplemental lighting, greenhouses are the future. However, older or economy greenhouses that take in unfiltered air from outside still have a medium amount of mold and contamination risk.

A greenhouse grow facility

Before building your greenhouse, study the area while taking into account climate, weather conditions and sun exposure. Excessively windy areas can blow in contaminants, and extremely hot climates make cooling the greenhouse interior a challenging and costly endeavor.

There are several simple operational tactics to reduce contaminants in a greenhouse. Add a thrip screen to keep insects out, thoroughly clean pad walls with an oxidizing agent after each cycle, and keep plants at least 10 feet from pad walls. Plan to flip the entire greenhouse at once so that you can clean the greenhouse top to bottom before your next crop. A continuous harvest in your greenhouse allows contaminants to jump from one plant to the next and reduces the ability to control your environment and eliminate problems at the end of a cycle. Lastly, open shade curtains slowly in the morning. This prevents temperature inversion and condensation, which can cause water drops to fall from the ceiling and transfer contaminants onto plants below.

Indoor

An indoor environment offers ultimate control to any grow operation. Cultivators can grow high-quality cannabis with the smallest potential for yeast and mold growth. Unfortunately, indoor environments are extremely expensive, inefficient and environmentally costly.

Talltrees
An indoor cannabis operation set up (Image: Tall Trees LED Company)

With indoor grow environments, keeping mold and contaminants at bay comes down to following a regimented plan that keeps all grow aspects clean and in order. To keep your grow environment clean, change HVAC filters multiple times a month. It’s also important to install HEPA filters and UV lights in HVAC systems to further reduce contamination threats. Clearly mark air returns if they are near the ground and keep those areas free of clutter. They are the lungs of your grow. Also, stop using brooms in the grow space. They stir up a lot of contaminants that have settled to the floor. Instead, use HEPA filter backpack vacuums or install a central vacuum system. Set up a “dirty room” for anything messy on a separate HVAC system, and be sure to thoroughly clean pots after every harvest cycle.

Learn more about reducing mold and contaminants in an indoor or greenhouse grow in another article from our series: 10 Ways to Reduce Mold in Your Grow.

Colorado Issues Recall, Pesticides Found In Cannabis

By Aaron G. Biros
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Last week, the Colorado Department of Revenue (DOR), the Colorado Department of Agriculture (CDA) and the Colorado Department of Public Health and Environment (CDPHE) announced a health and safety advisory for a large number of cannabis products grown and produced by Tree of Wellness Inc., doing business as Tree of Wellness. The health and safety advisory, synonymous with a product recall, was issued due to the detection of off-label pesticides in cannabis grown by Tree of Wellness.

Tests found Myclobutanil present in batches going all the way back to May, 2017, with some contaminated batches as recent as late October.

According to the press release, the CDA confirmed the presence of Myclobutanil, a near-ubiquitous fungicide used in a wide range of agricultural practices. The chemical has been a thorn in the side of the cannabis industry for being used off-label, or inappropriately, on cultivating cannabis.

Here are the batch numbers included in the recall

Myclobutanil is the active ingredient in Eagle 20, a pesticide used frequently in other agricultural fields like grapes, apples and spinach. According to UC Davis professor and Steep Hill scientist Dr. Don Land, Myclobutanil becomes significantly more dangerous when heated, or smoked. That chemical reaction produces hydrogen cyanide, an extraordinarily toxic chemical. Because of this, and the lack of research on what happens when these chemicals are burned or heated, there is a growing public concern that cannabis laced with a chemical like Myclobutanil can cause adverse health reactions.

The public health and safety advisory says they detected Myclobutanil in cannabis flower, trim, concentrates, and infused-products from Tree of Wellness. The CDPHE and DOR recommend consumers that have the affected products return them to where they were purchased for proper disposal.

Consumers in Colorado should check their labels to see if their products fall under the recall. Look for the Medical Optional Premises Cultivation License 403-00664 and/or Medical Marijuana Center License 402-00443. The recall includes batches of 23 different strains grown by Tree of Wellness.

Applications for Tissue Culture in Cannabis Growing: Part 3

By Aaron G. Biros
4 Comments

In the first part of this series, we introduced some relevant terms and principles to tissue culture micropropagation and reviewed Dr. Hope Jones’ background in the science of it. In the second part, we went into the advantages and disadvantages of using mother plants to clone and why tissue culture could help growers scale up. In the third part of this series, we are going to examine the five steps that Dr. Jones lays out to successfully micropropagate cannabis plants from tissue cultures.

Cleaning – Stage 0

Explant cuttings are obtained from mother plants. The cuttings are further separated into smaller stem pieces with a single node.

Micropropagation includes 5 stages. “Stage 0 is the preparation of mother plants and harvest of cuttings for the explant material,” says Dr. Jones. “To ensure the best chance of growing well in culture, those ladies [the mom’s] should be cleaned up and at their best. And hopefully not stressed by insects or pathogens.” She says growers should also make sure the plants are properly fertilized and watered before harvesting explants. “Obtaining the explants is done with a clean technique using new disposable blades and gloves,” says Dr. Jones. “Young shoot tips are harvested and placed in labeled, large Ziploc bags with a small amount of dilute bleach and surfactant solution, then placed in a cooler and taken to the lab.” This is a process that could be documented with record keeping and data logs to ensure the same care is taken for every explant. “Once in the lab, working in the sterile environment of the transfer hood, the cuttings are sterilized, typically with bleach and a little surfactant, and then rinsed several times with sterile water,” says Dr. Jones. Once they reach the sterile environment, Dr. Jones removes the leaves and cuts the stem down to individual nodes.

Establishment – Stage 1

Established explants propagating shoots

Establishment essentially means waiting for the shoots to develop. Establishing the culture requires an absolutely sterile environment, which is why the first step is so important. “Proper explant disinfection is equally as important is the control parameters of the facility itself,” says Dr. Jones. Mother plants are not grown in sterile facilities, but in an environment that is invariably contaminated with dust, which harbors micro-organisms, insects and other potential sources of contamination, including human handling. We discussed some of this in Part 2.

Explants, once sterilized and placed in the culture vessel, must establish to the new aseptic conditions. “Basically Stage 0 ends when the explants are cleaned and placed in the vessel. Stage 1 begins on the shelf while we patiently sit, watch and wait for the shoot growth,” says Dr. Jones. “Successful establishment means we properly disinfected the explants because the cultures do not become contaminated with bacteria or fungi and new shoot growth emerges.”

Multiplication – Stage 2

Stage 2 involves subculturing an explant to produce new shoots

This stage is rather self-explanatory as multiplication simplified means generating many more shoots per explant. In order to create a large number of plants needed for meeting the demand of weekly clone orders, Dr. Jones can break up, or subculture, one explant that contains multiple numerous new shoots. “Let’s say one vessel, which originally started with 4 explants each developed four new shoots. Working in the hood, I remove each explant from the vessel and place it on a sterile petri dish. Now I can divide each explant into 4 new explants and then place the four new explant cuttings into their own vessel. In this example, we started with one vessel with 4 explants,” says Dr. Jones. “Which when subcultured 4-6 weeks later, we now have 4 vessels with 16 plants.” This is instrumental in understanding how tissue culture micropropagation can help growers scale without the need for a ton of space and maintenance. From a single explant, you can potentially generate 70,000 plants after 48 weeks, according to Dr. Jones. “Starting with not 1, but 10 or 20 explants would significantly speed up multiplication.” Using tissue culture effectively, one can see how a grower can exponentially increase their production.

Rooting – Stage 3

“When the decision is made to move cultures to the rooting stage, we typically need to subculture the plantlets to a different media formulated to induce rooting,” says Dr. Jones. “In some instances, the media is very dark, and that’s because of the addition of activated charcoal.” Using activated charcoal, according to Dr. Jones, helps darken the rooting environment, which closely mimics a normal rooting environment. “It helps remove high levels of cytokinin and other possible inhibitory compounds,” says Dr. Jones. Cytokinins are a type of plant growth hormone commonly used to promote healthy shoot growth, but it is important to make sure the culture contains the right ratio of hormones, including cytokinin and auxin for maximum root and shoot development. Dr. Jones suggests that growers research their own media formulation to ensure nice, healthy roots develop and that no tissue dies in the process. “With everything I grow in culture, when it comes to media, in any stage and with all new strains, I run some simple experiments in order to refine the media used,” says Dr. Jones. She puts a special focus on the concentrations and ratios of plant hormones in formulating her medias.

After harvesting and multiplying, these explants are ready for rooting

“We commonly think of auxin’s role in rooting, but it’s also important in leaves and acts as a regulator of apical shoot dominance,” says Dr. Jones. “So having no auxin may not be ideal for the shooting media used in Stages 1 and 2.” Auxin is a plant hormone that can help promote the elongation of cells, an important step in any plant’s growth. “And cytokinins are typically synthesized in the root and moves through xylem to shoots to regulate mitosis as well as inducing lateral bud branching, so again finding that nice balance between these two hormones is key.”

Acclimation & Hardening Off – Stage 4

“When plants have developed good looking healthy roots, it’s time to pop the top,” says Dr. Jones. This means opening the vessel, another risk for contamination, which is why having a clean environment is so crucial. “The location of these vessels needs to be tightly controlled for light, relative humidity, temperature and cleanliness.” In the culture, sugar is a main ingredient in the medium, because the growing explants are not very photosynthetically active. “By opening the lid of the vessel, carbon dioxide is introduced to the environment, which promotes and enhances photosynthesis, really getting the plants ready for cultivation.”

Harvesting explant material from mother plants

The very final step in tissue culture micropropagation is hardening, which involves the formation of the waxy cuticle on the leaves of the plant, according to Dr. Jones. This is what preps the plant to actually survive in an unsterile environment. “The rooted plants are removed from the culture vessel, the media washed off and placed in a potting mix/matrix or plug and kept in high humidity and low light,” says Dr. Jones. “Now that there is no sugar, contamination is no longer a threat, and these plants can be moved to the grow facility.” She says conditioning these plants can take one or two weeks. Over that time, growers should gradually increase light intensity and bring down the relative humidity to normal growing conditions.

Overall, this process, if done efficiently, can take roughly eleven weeks from prepping the explants to acclimation and hardening. If growers perform all the steps correctly and with extra care to reduce risks of contamination, one can produce thousands of plants in a matter of weeks.

In the fourth and final part of this series, we are going to dive into implementation. In that piece, we will discuss design principles for tissue culture facilities, equipment and instrumentation and some real-world case studies of tissue culture micropropagation.