Vacuum ovens and rotary evaporators may be counterproductive when producing medical cannabis extract

Ninja Fruit

In a recent study published in the Journal of Industrial Crops and Products looking at cannabinoid and terpenoid profiles produced by popular extraction methods found using a combination of polar and non-polar solvents had a superior profile over other mixtures. When using an ethanol/hexane solvent mixture researchers were able to extract the highest levels of both cannabinoids and terpenoids compared to using one solvent.

Additionally, when using either a vacuum oven, rotary evaporator or genital nitrogen evaporation, the study found that nitrogen evaporation is far superior to both a vacuum oven and rotary evaporator. Both vacuum ovens and rotary evaporators were found to destroy a significant amount of terpenoids and seem counterproductive in producing medical-grade cannabis extract. Lastly, the position of the harvested plant material had a significant impact on the number of cannabinoids and terpenes produced in cannabis oil. Scientists found more cannabinoids and terpenes in oil that was generated from plant material harvested closest to the light source.

The findings of this study are significant to the home cultivator because one does not need expansive equipment to make high-quality cannabis oil. To receive the same results, one would merely create a cannabis tincture and let the alcohol slowly evaporate.


Namdar, D., Mazuz, M., Ion, A., & Koltai, H. (2018). Variation in the compositions of cannabinoid and terpenoids in Cannabis sativa derived from inflorescence position along the stem and extraction methods. Industrial Crops and Products113, 376–382.

Past grows of mine

Unfortunately, the lousy weather and finishing up prerequisites for graduate school has reduced my time to post. To continue to add content here, are some of my past grows. Two grows are done in a propriety blend of super soil, one in no-till and one grown hydroponically in coco. All were raised last year around this time.

Neem cake for a natural insecticide while growing cannabis.


One benefit of growing your cannabis is knowing what goes into your plant. Although, Massachusetts forbids dispensaries using insecticides when growing cannabis there are ways dispensaries can circumvent this regulation. Silly enough, Massachusetts list the names of prohibited pesticides the state tests for when inspecting cannabis. This means that there are a large number of commonly used insecticides that will fail to show on state inspections. Given the history of making money and people’s greed, it is only a matter of time that a dispensary in Massachusetts will try to use a prohibited insecticide

Azadirachtin is a natural insecticide found in the Neem tree. The Reader may already be familiar using a neem oil/dish soap solution as a foliar spray to control for insects. Producers of Neem oil, press the plant to extract the oil. However, not all the active ingredient in neem is isolated. Neem cake is a product leftover from the pressing of neem for oil. Neem cake has approximately one third to half the strength of Azadirachtin in it compared to neem oil. Neem cake elicits a defense through many anti-insect, and anti-fungal agents contained in the cake resulting in a systemic resistance against evasive insects and problems such as powdery mildew.

Neem cake has a wide variety uses for the organic grower. Neem has an estimated NPK value of 6-1-2. Additionally, the cake is full of micro-nutrients as well as trace elements, growth hormones, and Vitamin C.

A gardener can either use the cake as a soil amendment, top dressing or tea. One popular method for neem cake is a tea mixture including kelp and silica. Kelp is full of beneficial macro and micronutrients. Also, silica has insecticide properties as well as it strengthens the plant structure.

5 gallons of reverse osmosis water

  • ½ cup of neem cake/meal
  • ¼ cup of kelp meal
  • 1 tsp of silica

For a small 1-gallon mixture

  • 2 tbsp of neem cake/meal
  • 1 tbsp of neem cake
  • ¼ tsp or 1 mL of silica

Mix in a bucket of water and bubble for 24 to 48 hours. Feed it to the plants for routine pest management.

Just discovered this news article.

Medical marijuana dispensary shut down after insecticide found in sample


Thank you to the community of dank growers out there that share evidence-based information!

Improving Cannabis Crop Production With an Induced Low-Frequency Magnetic Field

IMG_1694Growers in Massachusetts must grow cannabis from seed. Germination is the process by which an organism is produced from seed. The Seedling stage is the most vulnerable part of a plant’s life. Therefore, increasing both germination and growth rate is a priority for all gardeners. Studies exposing a variety of seeds to an induced low-frequency magnetic field (25 mT to 200 mT) for a short period time (10-25 min) are shown to significantly improve germination and growth rate as well as the dry weight of many plants including hops. Hops are a close relative to cannabis. The cost of producing a low-frequency magnetic field is inexpensive. Therefore, it would be of benefit for cannabis growers to experiment with an induced low-frequency magnetic field to increase crop production.


De Souza, A., Sueiro, L., García, D., & Porras, E. (2010). Extremely low frequency non-uniform magnetic fields improve tomato seed germination and early seedling growth. Seed Science and Technology, 38(1), 61-72.

De Souza, A., García, D., Sueiro, L., & Gilart, F. (2014). Improvement of the seed germination, growth and yield of onion plants by extremely low frequency non-uniform magnetic fields

Iqbal, M., ul Haq, Z., Malik, A., Ayoub, C. M., Jamil, Y., & Nisar, J. (2016). Pre-sowing seed magnetic field stimulation: A good option to enhance bitter gourd germination, seedling growth, and yield characteristics

Maffei, M. E. (2014). Magnetic field effects on plant growth, development, and evolution. Frontiers in Plant Science, 5, 445.

C. Sativa: Primordia growth

Primordia growth C. Sativa.

This approximate four-week-old ninja fruit is starting to mature to adulthood. Primordium cells the are the smallest group of cell able to trigger organ growth. During this development phase, both pistillate (female) and staminate (male) of C. Sativa species are indistinguishable with the exception of general trends in shape.


Clarke, R. C. (1981). Marijuana botany an advanced study: The propagation and breeding of distinctive cannabis. Oakland, CA: Ronin Publishing.

Kidner, C. A. (2001). Plant organ primordia. Els () John Wiley & Sons, Ltd.