How to Increase Terpenes in Cannabis Plants
If you're new to growing or growing cannabis in general, terpenes are the compounds that give cannabis its flavor and aroma. They are a combination of carbon and hydrogen, classified by the number of isoprene units needed to build a molecule.
Not only are they responsible for the aromas and flavors of your cannabis buds, but they are believed to have numerous medicinal properties and affect the type of high users experience. Together with cannabinoids and flavonoids, terpenes form the so-called entourage effect.
About 10-30% of cannabis resin is made up of various terpenes. Some terpenes are found regularly in cannabis, while others are rare. The percentage of certain terpenes and the ratios in which they occur vary depending on the plant variety and environmental conditions.
Plants produce terpenes to attract pollinators, beneficial insects, and to repel animals or pests from the plant. Since cannabis plants are wind pollinated, they produce terpenes mainly to protect against herbivores and pests.
In cannabis plants, terpenes are produced in resin glands called trichomes. Thus, in order to produce more terpenes, cannabis plants need to produce more trichomes. There are many ways to help your cannabis plants produce more terpenes, and here are the most useful and common ones.
It all starts with good genetics. Even under the best conditions and with all the methods mentioned in this article, you won't be able to turn a weed into "top-notch" connoisseur buds. Because of the cannabis ban, breeders have primarily focused on getting the highest THC content possible.
And at the time it was the smart thing to do. Cannabis research has been very limited and we knew very little about other compounds found in cannabis. The pungent smell of cannabis was actually the opposite of what the producers wanted. This attracted unwanted attention and increased the risk of their arrest.
With the (re)legalization of cannabis, market needs have begun to change. Consumers not only wanted cannabis to give them a high, but they also wanted it to smell and taste good. As we researched the plant more, we found that terpenes also have medicinal benefits and effects.
In response to market demand, growers have begun to develop varieties with higher levels of terpenes. If you are using a remedy, you want to choose terpene-dominant strains that are best for your ailments. And if you are a smoker, you want to choose the flavors and aromas that you prefer. Typically, cannabis dispensaries offer terpene analysis alongside cannabinoids or list the dominant terpenes in their strains.
Across the European market, seed banks provide cannabis enthusiasts with the opportunity to purchase a wide variety of varieties and grow their own world-renowned genetics with impressive terpene profiles. Here are five of our favorite gourmet varieties!
Five Strains High in Terpenes
1. Guava Jelly
This tropical strain has a high limonene terpene profile and an impressive parent line consisting of Wedding Cheesecake, Strawberry Kush, OG Kush and Durban. Expect sweet notes of exotic fruits with a pungent, stinky undertone. Guava Jelly is available as a feminized seed and can be purchased here!
2. Skunk #1
Derived from many delightful parent varieties including Acapulco Gold, Colombian Gold and Afghan Indica. Skunk #1 is the strain that has influenced all modern hybrids. Known for its tangy skunky aroma, this classic variety is loaded with myrcene with sharp pinene notes to help bring out the iconic musky scent! Sensi Seeds catalog has regular, feminized and automatic versions of Skunk #1 available for all types of cultivators.
3. Girl Scout Cookies
Created from a plethora of cannabis cup winners, this recent addition to the cannabis scene has a remarkable pedigree of Durban, Hindu Kush and OG Kush. Its refined terpene profile includes an abundance of myrcene, pinene and linalool, which give way to sweet sandalwood flavors with earthy notes and a deep citrus aroma. Girl Scout Cookies seeds are available for purchase as a feminized variety.
4. Silver Haze
This award-winning variety has been rewarding users with its deliciously sweet terpene profile combined with a calming, invigorating effect since the early 90s and has been a fan favorite ever since. Known for its sweet citrus notes with heavy undertones of pine, sandalwood and citrus. Silver Haze, feminized and regular, has a great terpene profile and should not be underestimated.
A staple of the Dutch coffee house, the Tangie was bred from California Orange and Skunk #1. So, as you can imagine, it has an extravagant flavor profile rich in myrcene and limonene. Expect notes of fresh mandarin with lemon zest and a hint of musk.
While you can maximize terpene production in any grow system, soil is the best and most pristine environment when it comes to terpenes. High quality soil provides the best pH and alkalinity levels, maximizes nutrient uptake and keeps photosynthesis at optimal levels. Growing cannabis in native soil reveals the terroir of the region.
Terroir refers to the particular environment and environment in which the plants are grown. It is responsible for some of the unique flavors and aromas of plants. In the same way that wines produced in certain regions taste different even if they are made from the same grape variety, the same is true for cannabis plants.
Soil construction is a separate science. When it comes to terpene production, you want to increase the sugar content of the plants. Since plants do not absorb added sugars, your plant nutrition plan should encourage plants to produce their own sugars. Next, we will explain how to do this.
3. Nutrients, Supplements & Enhancers
Sugar or carbs are needed during the flowering phase if you want big, tight buds with higher resin and terpene content. Your cannabis plants will need varying amounts of carbohydrates throughout their life cycle. Carbohydrates have the most significant effect on the bud maturation phase.
Many nutrients and flavor enhancers are based on carbohydrates. This means they add sugar to the root zone to stimulate microbial populations. In turn, this gives the plants access to more sugar or nutrients.
There are also nutritional supplements that are slightly more specific for terpene production than carbohydrate-based supplements. They use naturally occurring plant compounds known as bio-osmotic enhancers that encourage plants to increase their production of terpenes and essential oils.
Bacteria often have a bad reputation. However, as we now know more about the microbiome and probiotics, we are beginning to appreciate the benefits. When you add lactic acid bacteria (LAB) to the soil, this special microbe will convert sugars into short chain fatty acids. Your plant will use them to produce more trichomes, cannabinoids and terpenes.
Using black grape molasses, whether in the soil or in your watering mix, will encourage microbial life in the root zone. The addition of molasses ensures that they can do their best so that plants can absorb nutrients faster and more efficiently.
Efficient use of nutrients results in increased trichome production, higher yields and overall plant health. When using molasses in an irrigation solution, mix two tablespoons with five liters of warm water.
The addition of amino acids such as fulvic acid and humic acid promotes the formation of chlorophyll and improves nutrient absorption. This in turn increases the ability of the plant to synthesize more of the sugars present in its metabolism, improves nutrient uptake, and increases the terpene content of your plants.
Many manufacturers have succeeded in increasing the content of terpenes with seaweed extracts. Seaweed extracts increase the bioavailability of trace elements. They also contain natural growth hormones that stimulate plant cell division. When applied to the root zone of a plant, seaweed extracts cause the development of heavier and more pronounced roots. Wider, thicker roots allow the plant to absorb more water and nutrients, increase carbohydrate production, and increase terpene content.
Keep in mind that the needs of plants change throughout their life cycle. During the last two weeks, nitrogen should be eliminated, as excess nitrate burns carbohydrates and wastes energy. This slows growth and reduces terpene production. Potassium levels, however, should be increased during the flowering stage, as this causes the sugar levels in the plant to rise.
Cannabis plants produce trichomes as a defensive response to various attacks and stresses. The natural function of the trichome glands is to protect the plant and its developing seeds from extreme conditions such as ultraviolet rays, cold weather, pests and diseases.
Gardeners can use this to their advantage. By causing mild stress during flowering, they can cause plants to produce more trichomes and therefore more cannabinoids and terpenes. However, too much stress is too harmful to plants and will stop photosynthesis. Thus, these methods do not work well on autoflowering plants due to their ability to complete a growing cycle in as little as 12–13 weeks; any additional stress can be detrimental and result in a poor harvest.
Cold weather, which is a significant stress for the plant, causes changes in the plant's metabolism. When this occurs in the final flowering stage, resin production is increased in exchange for very little yield loss.
You should gradually lower the temperature by about 5°C during the last two weeks of flowering. This mimics autumn conditions and signals to the plant that frost and winter are coming. The plant will react by using its remaining energy to produce more resin to protect its offspring.
At this point, the buds are fully ripe and just need to ripen. This results in much greater and higher quality resin coverage and terpene content. Reducing the temperature in the late stages of flowering can also speed up the flowering period and speed up the harvest.
The optimum humidity for cannabis flowering is 50-60%. Lowering the humidity to 30% will cause a little stress to the plants, and the production of terpenes will increase. This can be achieved by adding more fans or a dehumidifier to the room. Lower humidity will also help reduce the risk of mold and mildew.
When you water less and less, you are simulating a drought. As with any stress, the plant's natural response is to protect itself and its seeds. By coating flowers and seeds with a lot of resin, plants retain moisture and protect them from water shortages.
Slightly drying the growing medium will increase the content of cannabinoids and terpenes. This also ensures that the roots get more oxygen and speed up photosynthesis.
Defoliation is the most common and popular method of increasing sugar production and naturally increasing terpenes and cannabinoids. Pruning leaves increases terpene levels, redirecting energy to the buds.
Just cut off the young foliage as it grows. However, be careful not to overdo it because removing too much foliage will cause your plants to stop growing and slow down photosynthesis. Extreme defoliation will also reduce the yield and quality of your buds.
Remember that leaves are one of the most important factors in the production of sugar. The upper leaves catch the most sunlight. Therefore, remove them only if they block most of the developing kidneys.
Manufacturers' opinions on defoliation vary. But if done right, it can increase the yield, terpene and cannabinoid content of your plants.
Lolipoping is nothing more than defoliation, only on a larger scale. The goal is to remove the bottom quarter or third of the plant. The lower branches are exposed to less light anyway, and the buds that form on them will always be smaller and worse in quality than the upper colas.
Removing them at the beginning of the flowering stage ensures that the energy produced by the plant goes to the rest of the plant. This will increase not only your yield but also the overall quality of your buds.
Supercropping is a high stress growing method. It involves simply pinching and bending stems and branches. Damage to the inner fibers and leaving the outer shell intact promotes more vigorous bud growth and development, as well as increased production of cannabinoids and terpenes.
After the plants recover, you will notice that an "ankle" is forming at this point. A larger ankle surface will help the plant absorb more nutrients and transport them to the developing buds.
The best time for Super Crop is late in the growing season and the first two weeks of flowering. If you start super pruning a week before flowering, the plants will have enough time to recover. By doing this around the second week of flowering, you will help "stretch" and distribute the branches more evenly. But it will also help position the branches and buds and expose them to more light.
A flush is when the plant is watered with clean, nutrient-free water, and in the final weeks of harvest, some growers like to do a final rinse with ice.
This not only washes away stored nutrients, but also increases stress on the plant. As a natural response to any pressure, the plant produces more trichomes and resin in the final days of flowering.
While some growers like to use this technique in the final days of flowering, this method is not recommended, especially for beginner growers. Theoretically, stem splitting will cause hormonal changes in your plants due to severe stress. Plants will stop producing buds, but resin production, as well as cannabinoid and terpene levels, will increase.
We do not recommend this method, as you can introduce an infection that can bring various diseases and lead to the death of the plant. If you're not careful, you can also cut the plant completely, resulting in a premature harvest.
5. Companion fit
Companion planting is common in many crops and integrated pest management systems. This is a method in which farmers use different plants to grow their main crop. By planting certain crops next to each other, they work together to improve the production and quality of their products.
They usually do this to attract pollinators and beneficial insects, repel pests, add nutrients to the soil, or extract minerals from the earth. Some plants have been shown to increase the levels of essential oils and sugars in neighboring plants.
Some plants known to increase essential oil production and enhance flavor are nettle, yarrow, basil, chives, and tarragon.
Lighting plays a crucial role in the entire growing process. This ensures that your plants develop properly, increasing the yield and overall quality of your buds. Different lighting and light spectrum cause (slightly) different terpenes or even terpene profiles. The same strain grown outdoors under the sun will have a slightly different chemical profile than one grown indoors under HPS or LED lights.
When it comes to terpenes, two types of light spectrum play a particularly important role. If you exclude the red spectrum in the last 72 hours of growth, the plant will continue to synthesize terpenes, but they will not be released. This leads to the accumulation of terpenes in the maturing buds.
The second important light spectrum is UV-B. As we mentioned earlier, one of the reasons cannabis plants produce trichomes is to protect the plant from harmful UV rays. However, this can be used to your advantage. If you use UV-B light in your environment, you can get your plant to produce more trichomes and therefore more terpenes. Adding 10-20 watts of UV per square meter for the last 2-3 weeks will increase the amount of terpenes in your buds.
HPS lamps already emit a large infrared peak in the 800 to 900 nm range and do not require an additional UV-B source. If you are growing outdoors, make sure your buds are positioned correctly so that they all get enough light.
7. Reduce your CO2
During photosynthesis, plants take in water and carbon dioxide (CO2) and convert them into oxygen and glucose (sugar). Many growers introduce additional CO2 into their growing environment to speed up and increase this process.
The most suitable time is the first two to three weeks of flowering. By the end of the flowering period, buds form in plants. It remains only to let these buds fully mature.
Reducing the level of CO2 in the atmosphere causes plants to produce more ethylene. Ethylene is a hormone necessary for the maturation process. Increasing ethylene production stimulates trichomes to put more energy into resin secretion and thus increases terpene levels.
As your plants grow, they need nutrients to form leaves, stems, branches, and buds. Nutrients are taken up from the growing medium through the roots and stored in the leaves and buds. When your plants have reached their last stage, you should stop feeding them.
Generally, growers tend to give their plants clean water during the last two weeks. This ensures that any excess nutrients that the plant does not need or cannot use are flushed out. Remaining nutrients can leave an unpleasant flavor and aroma and cause buds to burn unevenly. Clean, reddened buds leave a nice, natural, aromatic end product.
To get the most out of flushing, growers can flush the soil with 3-5 times the amount of clean water equal to the volume of dirt in the container. So, if your container holds 5 liters, you will need 15-25 liters for flushing. Unlike watering your plants with just water for the last two weeks, this ensures that any remaining nutrients are also flushed out of the soil. When you have done this, let the soil dry well and keep watering the plants with clean water.
9. Harvest at the right time
Knowing when to harvest is especially important, and the same goes for terpenes. As the plants mature, their smell becomes more intense, and sometimes even changes. As with cannabinoids, the best time to harvest is when the trichomes start to turn amber.
If you harvest too early, your buds will have fewer trichomes and therefore fewer cannabinoids and terpenes. If you harvest too late, the trichomes will break down and you will start to lose both terpenes and cannabinoids.
Choosing the right time of day
Plants constantly produce terpenes, but they evaporate under the pressure of (sun) light and rising temperatures. Terpene levels increase in the dark and peak just before sunrise. During the day, terpenes evaporate and fill the surrounding air with a scent that warns predators and pests. This means that plants have more terpenes at the end of darkness than after full daylight hours, and terpene content is lowest at dusk.
The best time to harvest is therefore just before sunrise outdoors or just before the start of the indoor light cycle. Some growers even like to leave plants in the dark for 24 or 48 hours before harvest. This guarantees the maximum content of terpenes.
10. Drying and curing
Proper drying of your buds is crucial in any growing and can make the difference between a good harvest and a bad one. Since they are often in a hurry to taste the fruits of their labor, they speed up the process. To properly dry cannabis buds, you need a dark place, a constant humidity of 45-55% and a temperature of 20-22°C.
The even and slow process ensures that you retain the terpenes and cannabinoids from your buds. The slower the drying process, the better. The proper drying process usually takes about 2-3 weeks, depending on your drying method.
After you've dried the buds, they need to be cured. Curing is simply a continuation of the drying process, which takes anywhere from 4-5 weeks to several months. Some changes, like converting THC to CBN, will happen, but when it comes to terpenes, longer cure times are better.
In the first few weeks, the level of cannabinoids and terpenes will decrease. After a few weeks, these levels will begin to increase. Typically around the eighth week, terpenes are at their lowest in the curing process.
But after the 8th week, they begin to rise again, even above the level of a freshly cut plant. Depending on the atmosphere in which the buds are stored, i.e. air, vacuum, N2, argon or CO2, you may even see an increase of up to 20%. If you speed up the drying and ripening process, there's a good chance your buds will have the scent and taste of hay or chlorophyll.
Terpenes, like cannabinoids, are produced in the trichomes or resin glands of the plant. Cannabis plants produce trichomes in response to stress and environmental conditions. Enough stress on the plants and providing them with optimal growth conditions will help produce more trichomes and terpenes. After thorough drying and curing, the buds will be fresh, fragrant and tasty.
If you've had any encouraging interactions with increasing terpene levels in your plants, or if you'd like to share your own experiences with terpenes and cannabis, please let us know in the comments below!