Cannabis seeds germinate when a small white rootlet emerges. (Courtesy of Jorge Cervantes via "The Cannabis Encyclopedia")

How to germinate weed seeds: Join forces with Mother Nature

Renowned grower Jorge Cervantes will answer readers’ questions and give advice on all things related to the cannabis plant. Got a question for Jorge? Email him at

Editor’s Note: Laws for cultivating cannabis vary from state to state and city to city — before germinating any seeds or planting any clones, take care to learn what your local laws are.


Question: What’s the best way to start growing a marijuana plant from seed?

Answer: Seeds germinate when a small white rootlet emerges. Water, heat and air (oxygen) are all that cannabis seeds need to break dormancy and germinate. Fertilizer, “special” hormones and “secret” additives are not necessary, and are a waste of time and money. Mother Nature provides seeds with a stored food supply to usher them through germination. Strong, viable seeds germinate in two to seven days. At germination, the seed’s protective shell splits and a tiny white rootlet (tap root) pops out.

Cannabis Seed Germination: Step-by-Step

Step One: For best results, soak seeds for 12-24 hours in a glass of clean water. At first, seeds will often float on the surface. They should sink to the bottom of the container after a few minutes. Soaking ensures that water penetrates the protective shell to activate growth hormones. Avoid soaking seeds in excess of 24 hours. This causes them to suffer oxygen deprivation and drown, prompting seeds to rot.

Step Two: Carefully remove seeds from the container of water. I like to pour water and seeds onto two to four paper towels that are contained by a saucer or plate. Once they are in place, cover the seeds by folding the towels to cover them.

Step Three: Tip the plate at an angle so that all excess water drains freely away. The paper towels should be evenly moist, with no standing water on the plate.

Step Four: Place the seeds in a warm, shady-to-dark location. The ideal temperature range is 70°F to 80°F for fastest germination. Make sure seeds are covered and in the dark. Another variation is to set the paper towels on a grate so that excess water drains away freely. The grate also allows for plenty of air (oxygen) circulation.

Step Five: Touch the towels to check the moisture level two to three times a day. You may need to add water once or twice during the day depending on ambient room humidity and temperature. Keep the towels evenly moist. NEVER let the towels and seeds dry out.

DO NOT let seeds sit in standing water. Excess water must drain away freely. The paper towels are able to retain sufficient moisture to prompt germination in 36 to 96 hours. Of course, some seeds may germinate sooner, and others will take longer, especially older and weaker seeds.

If mold is a concern, take prophylactic measures; add a mild organic fungicide or 2 percent mix of bleach to irrigation water. To get the 2 percent solution, use 2 fluid ounces bleach in 98 ounces water (or 1 ounce bleach in 49 ounces water.)

More more info on the next steps, see this related post: “How to Plant Cannabis Seeds.”

Your opinion is valuable:
Please tell us how you germinate seeds in the comment section below. Our readers want to know your tips and tricks!

Check out The Cannabis Encyclopedia (available at covering topics such as “Germinating Old or Stressed Seeds,” “Increase Yields,” “Germinate Hard-Shelled Seeds,” “Feminized Seeds,” “Autoflowering Seeds” and “Planting by the Moon.”