Growers use the Plant Sex Test to identify male and female plants at the seedling stage, and it can be done as early as 7-10 days after the seed has germinated. This is a huge advantage versus waiting up to 2 months for plants to show their sex.

Identifying males early means saving a significant amount of time and resources, avoiding the risk of crop pollination, and increasing grow space. All types of cultivators use the Plant Sex Test, from small home growers to large-scale commercial operations.

   “DNA-based method that identifies the Y chromosome in seedlings—because just like humans, only male plants have an Y chromosome”

 “The only company that tests the cotyledon (the round non serrated leaf that first to emerges ), so they can test your plant sooner without slowing its growth and stressing it”

 Identifying males early means saving a significant amount of time and resources, avoiding the risk of crop pollination, and increasing grow space.


“Knowing that you are able find out the female/male ratio of your seedlings in a very early stage, makes hunting high quality seeds even more fun”

“Phylos is prompt, professional and 100% accurate. We’ve been able to crack many more seeds than we would have otherwise, giving us access to significantly broader genetic diversity.”

Matt Walstatter, Owner/CEO

Pure Green, Portland (OR)

“If time is money, the Plant Sex Test is priceless. The ability to cull males in a matter of days not months is a game changer!” Jerry Whiting, Owner

LeBlancCNE, Seattle (WA)

“We just finished a seed crop of 500 phenotypes of 10 different strains. Not having to spend time and effort searching for males was a big saver of production space, labor, and bottom line: money.” Mike Leigh, Cultivation Director

Pure O&M, Boulder (CA)

Phylos emails your results 48 hours after receiving your samples

Collection of your samples

How do I collect the samples for the plant sextest?

Be sure to read the instruction card included in your kit carefully before beginning to collect samples. Please reference the sample collection videos below depending upon the Plant Sex Test product you are using:

88 Seedling plate

4 Seedling card 

Why do you want me to use cotyledon leaves?

There are a number of reasons. 1) Taking a sample from a cotyledon leaf is the fastest way to identify the gender of your seedlings. 2) There is no THC in cotyledon leaves making samples legal to send in the mail.

Our tests were designed to be in compliance with the Controlled Substances Act.

What scientific test you use?

Back at the lab, we extract DNA from your sample collection cards and use qPCR analysis to identify the Y chromosome. All cannabis plants have an XX or XY combination, indicating a female or male plant at a genetic level.


Is it legal to send my samples in the mail ?

Yes. We designed our collection methods to be legal to send across state lines. Our kits are designed to collect a DNA smear from cotyledon leaves, which means there’s no THC and no plant tissue.

NOTE: The lab is closed on weekends, so plan for your samples to arrive on a Monday or Tuesday to avoid weekend gaps.

Do you ship internationally?

Yes! International shipping times vary by carrier and destination. Standard international shipping typically takes 5-10 business days to reach your country.  If you are situated in Europe we can ship within 2-3 businessdays

Expedited shipping options are available upon request for an additional fee.

Where do i send my sample to?

With your kit you’ll find shippinginstructions and shipping adress. There is no information of the sender needed. 


Is there a seperate charge for the results?

No. The price of the test includes the sample collection kit, testing, and results

When do i get my results?

Results will be available within two business days of the lab receiving your samples. During peak season (March-May), results may be delayed due to high volume. You can track the status of your order within your Phylos account

Where do I access my results?

You can access results and the status of orders within your Phylos account.

Plant Sex Test

Early Y Chromosome Detection for Cannabis Seedlings


   – Save time, money and resources.

– Lightning-fast turnaround time. Results available online.

   – No guesswork anymore. Accurate results—every time!

   – Legally and discretely send samples in the mail.

   – Access results status of orders within your account.