The Top 10 Benefits of Early Cannabis Sex Testing​

At Nova Labs, we specialize in early sex testing for cannabis plants using advanced PCR technology. By testing plants at the seedling stage, cultivators gain invaluable insights to inform key decisions around spacing, planning, and managing inputs for higher quality yields.


Below we have outlined the top 10 reasons our cannabis producer clients test with Nova Labs:


1. Maximize Yields

Female plants produce the high-value cannabinoid-rich flowers for consumption. Early testing allows removing non-productive males right away so all resources go only to flowering plants.


2. Optimize Grow Space

Half of cannabis seeds produce males taking up space for weeks before showing sex. Early testing enables using 100% of costly indoor/greenhouse space for flowering plants only.


3. Reduce Risk

Undetected males can pollinate flowers causing 70%+ potency loss from seed production. Testing eliminates males before releasing pollen that can destroy a crop.


4. Save Resources

Males consume light, nutrients and labor before proving useless. Early testing ensures inputs get used only on flowering female plants.


5. Accelerate Harvests

Testing informs spacing for faster, denser flowering canopy expediting harvests for quicker returns. Tight spacing also boosts uniformity and quality.


6. Strain Verification

PCR testing provides genetic confirmation of purchased seeds or clones ensuring true-to-label strains free of contamination improving consistency.


7. Customer Assurance

Buyers are demanding clean cannabis free of seeds and consistent experiences. Reliable testing and elimination of males prevents quality issues ensuring consumer confidence.


8. Regulatory Compliance

Many states prohibit males for personal and commercial grows. Early testing provides confirmation of all-female crops meeting legal requirements.


9. Data & Forecasting

Test results deliver analysis of female-to-male ratios from plant batches informing accurate yield forecasts and business planning.


10. Breeding Selection

Testing allows identifying and isolating superior female breeding stock for developing desired flower traits and maximized cannabinoid and terpene outputs.

It is usually best to assume a 50:50 female-to-male ratio when working with regular cannabis seeds. This means germinating twice as many seeds as the desired number of plants to account for culling half the males.


However, in practice, the natural ratio is approximately 65% female plants and 35% male plants. This skewed ratio exists because cannabis spreads pollen through the air without insect pollinators, requiring fewer male plants.


We have incorporated both ratios into the table below to cover the typical assumption (50:50) as well as the more biologically accurate 65:35 ratio. Showing both ratios demonstrates the significant potential gains in healthy flowering crop that early sex testing enables, whether working from the conservative 50:50 or the natural 65:35 female-biased figures.


Stressful growing conditions can increase the chances of plants turning male, making the 50:50 ratio a safer assumption for regular seeds. By detecting and removing males early via testing, the natural higher female tendency can be taken advantage of for maximizing productive flowers.


Here is the table showing the percentages of healthy crop based on early sex detection in cannabis plants:

Timing of Sex Detection % Healthy Crop* % Healthy Crop*
No sex detection 50% 65%
Sex detection at pre-flower (4-6 weeks) 75% 82.5%
Sex detection at early vegetative stage (2-3 weeks) 90% 92.5%
Sex detection at seedling stage 95-100% 97.5-100%