A Homegrower’s Guide To Testing

One of the most frequently asked questions our staff answers is: do you test for home growers? And if so, what kind of tests should I have performed?

The answer is yes, we test for home growers. We test for anyone in the state of Massachusetts who has a cannabis product they would like to know more about, whether they cultivated/ produced it themselves or bought it from a dispensary or other source. 

But what tests you should have performed is a bit more specific to your grow, and even individual plants within your grow. Let’s go through each of the tests we offer, and what kind of situations they would be appropriate for. 

Cannabinoid Profile

Cost: $50 per sample

Scope: THCa, CBGa, CBCa, THCVa, Δ-8 THC, CBD, CBN, CBL, CBDV, THCV, CBNa, CBDa, CBLa, CBDVa, Δ-9-THC, CBG, CBC, CBT, CBCV

Our most popular test by far, a cannabinoid profile will tell you how rich your plant is in certain cannabinoids, like THC and CBD. While the concentration of THC is far from the only indicator of quality, it’s still an important factor to be aware of especially if the flower will eventually be consumed. 

Knowing how much THC, CBD, or other cannabinoids a plant contains will help with dosing, especially when it comes to turning that plant material into edibles or other infused products. Refining formulas and recipes is a lot easier when you’re sure of the exact concentration of cannabinoids present in the flower used.

This test can also be vital for growers experimenting with cultivating strains high in lesser-known cannabinoids like CBGa and THCVa. 

Terpene Profile

Cost: $25 per sample

Scope: alpha-Bisabolol, delta-3-Carene, Caryophyllene-Oxide, Eucalyptol, Guaiol, Isopulegol, Linalool, cis-Nerolidol, Ocimene, alpha-Pinene, alpha-Terpinene, Terpinolene, Camphene, beta-Caryophyllene, para-Cymene, Geraniol, alpha-Humulene, D-Limonene, beta-Myrcene, trans-Nerolidol, beta-Ocimene, beta-Pinene, gamma-Terpinene

A terpene profile is another great indicator of quality, as terpenes are responsible for the smell and taste of cannabis flower. Some researchers believe terpenes also contribute to the entourage effect, working synergistically with cannabinoids to create the physiological effects that come with cannabis consumption. 

Many homegrowers may concentrate on tweaking growing conditions to favor high cannabinoid concentrations, unknowingly sacrificing terpene quality in the same stroke. A terpene profile will reveal just how successful a grower was at maintaining that balance, and help inform future grow decisions. 

Plant Nutrition Analysis

Cost: $115 per sample

Scope: Boron, Calcium, Copper, Iron, Magnesium, Manganese, Molybdenum, Phosphorous, Potassium, Sulphur, Zinc

Analyzing the nutrients in your grow is a great way to save time, money, and resources. Without knowing the approximate nutrient content of a plant, it can be easy to overfeed and waste those expensive fertilizers. It’s also easy to underfeed, leading to deficiencies and toxicities that affect plant quality and yield. Identifying deficiencies and toxicities early on can allow homegrowers to resolve the problem as fast as possible and save on precious resources.  

Safety Screens

In general, safety screens are not as strongly recommended to homegrowers, especially those who are knowledgeable about their growing medium quality. However mold is something that cultivators have less control over, especially those growing in outdoor, humid environments, and oftentimes it cannot be visually spotted. 

Mold can pop up at any stage in the growing process, and can also be a problem during the drying and curing phase. Some mold cases may be identified by the mildew smell or even by sight, but in most cases it will remain well hidden inside the bud. Microbial contaminants are almost always too small to visually perceive.

Microbiological Contaminants Screen

Our microbiological screen will detect the presence of various bacteria and pathogens. However, we would not recommend purchasing this screen unless your grow is in a humid environment or you have another reason to suspect contamination or you are immunocompromised and need to be 100 percent sure you’re not consuming something that could be potentially harmful . 

Cost: $135 per sample

Scope: Total viable aerobic bacteria, Total bile-tolerant gram-negative bacteria, Total coliform bacteria, Total yeast & mold, Salmonella, Shiga toxin-producing E. coli (STEC)

Heavy Metals Screen

Another safety analysis that may be of interest to homegrowers is our heavy metals screen. Cannabis is a very adept bioremediator, meaning it will pull elements from their growth mediums such as soil or water at a high rate.

Heavy metals like lead or cadmium that were present in these growth mediums can accumulate in the plant structures that are eventually consumed or used in the production of cannabis products. While they may not be dangerous in small quantities, high enough concentrations of metals consumed on a daily basis can be quite harmful to human health.

Our heavy metals screen will detect the presence and concentration of four common heavy metals. We would not recommend this screen to those who have already tested their growth mediums, including water, soil, fertilizer, and nutrients.

Cost: $115 per sample

Scope: Arsenic, Cadmium, Lead, Mercury

While we were recently closed to the public for sample submission due to the COVID-19 pandemic, we have reopened for appointments which you can schedule at mcrlabs.com. Our new sample submission process is contact-free and was designed to keep our more vulnerable clients safe. Take a look at our sample requirements guide before you come in to ensure you submit enough sample for all the tests you would like performed.