Episode 62: Update on TAINTED VAPES plus Grow At Home

Best practices for growing top shelf cannabis at home from Jim Hole, VP Cultivation, Atlas Growers.


NEWS UPDATE! Before I tell you about this great interview please know that Matthew and I recorded the intro to this episode just as reports on tainted e-liquids in vaporizers were breaking. Since our recording there have been reports about tainted cannabis oils causing respiratory illnesses and deaths.

According to this excellent early report in Leafly health authorities in New York have confirmed that vitamin E oil, a cheap thickener, is the culprit in tainted vape cartridges in that state. The FDA is now looking at vitamin E oil (tocopheryl-acetate) to determine where it's being used.

There are three ways to protect yourself while vaping:

  • Only buy trusted brands that list ingredients and their lab testing results somewhere—on the package or a website. (Chronic Carts, Dank Vapes, and West Coast Carts are three brands that have be identified as producing tainted carts).

  • If you are uncertain of a product’s provenance, don’t use it. If you bought any cartridges on the street or off label and you don’t know the maker, throw them away.

  • Reports from Oregon allege that some tainted carts were purchased in legal dispensaries. If you’re hesitant about inhaling all oils consider vaporizing well-cultivated and well-cured flower instead.

What's going on now is reminiscent of bootleggers making bathtub gin during prohibition: Bad actors producing bad products in an unregulated market. Be smart!


This week’s interview is with Jim Hole, VP of cultivation at Atlas Growers, one of Canada’s most serious medical marijuana companies. The interview leverages Jim’s many years as a grower of all plants and is well worth a listen. Rather than me telling you about, I asked Jim to share his tips for growing at home. Cannabis isn’t difficult to grow, but following these guidelines will ensure better outcomes.


  • For home grows, LED (light emitting diodes) is a better choice than HPS (high pressure sodium). HPS can grow quality cannabis but they produce a lot of heat which can be tough to manage in household environments. Also, the light spectrum of HPS is heavily shifted towards the yellow and red spectrum whereas most LEDs have a better distribution of wavelengths with a good portion in the blue spectrum.

Light quantity

  • It’s best to gradually increase the quantity of light that the plants receive from the seedling stage to the flowering stage

  • At the seedling stage the plants require less than 1/10 the light they need at flowering. Gradually increasing the light over the growth cycle of the crop is ideal.


  • There are a number of different substrates that grow excellent cannabis

  • Garden soil can grow excellent cannabis, depending on its quality, but it is far too dense for pots. In addition, weeds, diseases and insects are often harbored in garden soil so it should be used with caution.

  • Potting mixtures with coarse-fibred sphagnum peat moss and perlite (white popped rock) work well, as do coir (coconut fibre) and rockwool

  • One of the most promising substrates is ‘biochar’. It is typically wood or plant stem fibre that is heated without being burned. The result is a skeleton of carbon with lots of pore spaces to hold water, oxygen, microbes and nutrients which is ideal for cannabis


  • There are almost as many ‘feed’ programs for cannabis as there are strains. But the basic rules remain. A good rule of thumb is to have a 2:1 ratio of nitrogen (1st number) to potassium (3rd number) in the vegetative stage and then reverse the ratio to 1:2 during flowering. Phosphate is the middle number on the label and should be applied at about a fifth of the nitrogen rate

  • Don’t forget to add Calcium, Magnesium and Sulfur to the feed program along with a complete micronutrient package

  • Some people prefer to feed more heavily once per week while others like to feed every time they water. It’s a matter of personal preference


  • Cannabis germinates rapidly and only takes a few days from sowing to seedling emergence

  • Temperatures around 22-25C (72-77F) are ideal for rapid and vigorous germination

  • Seed starter mixtures that have a fine peat moss blend work well but ensure that the mixture stays moist but not wet

  • A kit with S ‘peat pellets’ contained in plastic trays with a clear plastic dome, grow light and heat mat are also ideal for starting cannabis seeds

  • T5 fluorescent tubes provide plenty of light for the seedling stage

Things that many people often get wrong when growing cannabis:

1 Choosing poor quality cannabis seeds and the wrong varieties

  • Find the varieties that you want to grow and ensure that seeds look full and not cracked.

2 Growing too cold or too warm

  • Growing too cold slows growth dramatically while growing too warm stresses the crop and can damage flower buds. Start with temperatures between 20C and 26C and adjust based on the cultivar and experience with the crop

3 Over and under feeding

  • Fertilizer requirements increase from seed and up to maximum vegetative growth before decreasing in flowering. Underfeeding reduces plant vigor and growth whereas overfeeding burns roots.

4 Ensuring correct light cycle

  • For all strains that aren’t ‘autoflowering’ the vegetative phase requires long days (typically 18 hrs or more). Once flowering is required the light must drop to 12 hour days with uninterrupted darkness for 12 hours. Once a plant is in the flowering phase, long days can stop flower production and cause the plant to revert back to the vegetative phase.

5 Not paying attention to pest problems

  • Cannabis is prone to attack by spider mites, thrips, whitefly, powdery mildew and grey mold. Controlling pests early is always the best strategy.


  • Specialized equipment like trimmers and irrigation equipment are nice to have but what I call the ‘Big Three’ – light, substrate and fertigation -- have the greatest impact on crop yield and quality

  • Light is plant food. Plants harvest sunlight and use the energy to make sugars. Skimping on lights reduces yield and quality. There is a saying that for every 1% increase in light, there is a 1% increase in yield. Get quality lights that are durable and can provide plenty of light energy

  • Substrate is anything that the roots grow in. The primary job of any quality substrate is to provide an environment that supports the correct balance of air, water and nutrients. It should also be pest free.

  • Fertigation is fertilized water. Ensure that the blend is high quality and provides all of the nutrients that cannabis plants require. Any nutrient that is missing or deficient becomes the limiting factor for successful yield and quality.

Joe Dolce