Before Collecting Samples

Please read the entire instructions carefully before taking your samples. Download a printer friendly version here.

Order kits. Then, gather the required tools and supplies (see list below).

Do not use dead, yellow or brown leaves. The ideal time to sample is right after the first true (serrated) leaves emerge, usually around 7-10 days post-germination. Please DO NOT use true leaves, use cotyledons (round leaves) to get the best sample.

Water your plants 24-48 hours before collecting samples.

Label plants and DNA Collection Kits before starting to ensure each sample is tracked back to the correct plant. You can download your Sample Collection Form here. 

Avoid cross-contamination during sample collection by wiping your tools with alcohol before and after working with each plant.

You Will Need

Nitrile or Latex gloves

Nitrile or Latex gloves
​To help to reduce the risk of cross-contamination


For plucking leaves


To cut leaf samples from plant

Alcohol (70% isopropyl or ethyl)

Alcohol (70% isopropyl or ethyl)
To wipe clown tools before and after each plant DNA sample is collected




A clean working surface

To document and collect DNA samples


A blunt object

Sturdy enough to crush leaves (e.g. a coin, marker or key)

A sample collection form

To track your samples and ensure correct labeling. You can avoid writing out names by hand, (and save time, especially for large orders), by downloading your Sample Collection Form here, then sharing it with when you mail back your samples.

Click on the image above for a downloadable version of the form.

Collecting Plant DNA Samples

Step 1

Identify and cut a cotyledon from your plant. Place the cotyledon between the plastic cover and filter paper.


​Close the plastic cover and place on a solid surface.


Use a coin or blunt object to crush your sample through the plastic film. Continue until the leaf soaks fluid completely through both sides of the filter paper, leaving a dark green spot the size of your fingernail.

​​STEP 4

Remove leaf remnants leaving behind only what was absorbed by the paper.


Place sample inside the envelope then clean your tools, including the object used to crush your sample


Please do not seal the envelopes. Simply close the flap and use rubber bands to group batches of envelopes when you’re done. Download your Sample Collection Form here, then share it with 

Cannabis cotyledons

Examples of Well Collected Samples

Examples of Poorly Collected Samples

Submitting Your Samples

A plant DNA sample

Send samples to:


Delta Leaf – Kit Returns
81 David Love Place #112N
Goleta, CA 93117

Click the image above to view a sample results datasheet

Samples collected using our protocols are free of any plant material and regulated substances. Delta Leaf does not accept samples containing plant material or any regulated substances.

Need additional guidance collecting DNA samples?