If you want to grow weed, then there are two ways to start: with a clone or from seed. If you are starting with seeds, this article is for you. In this article, we explain what causes seeds germinate, and the best methods you can use to germinate your seeds and start the growing process.

What causes marijuana seeds to sprout?

Seeds normally sprout when subjected to warmth and humidity. In nature, this occurs when the seed falls from the plant during the winter months and goes underground. As the season changes to spring, the earth becomes warmer, which causes the seed to sprout.

When you are growing cannabis indoors, you must mimic these environmental conditions to get your seeds to sprout. But with all things related to cannabis cultivation, there is more than one way to skin a cat. There are so many different way to grow weed, and even when it comes down to popping seeds, there’s more than one way to do it.

How Long do Cannabis Seeds take to sprout roots?

It all depends on the temperature. The warmer and more humid the environment, the quicker they will sprout. When using the paper towel method along with some warming pads, it is possible for the seed to sprout within 24 hours. Most typically, it will take a seed at least 2 or 3 days.

If the seed is left at room temperature, it will take more like 5 or 6 days for the tap root to sprout.

Methods for Sprouting Cannabis Seeds Indoors

There are many ways to sprout marijuana seeds, and this article only covers a few. But once you understand the fundamentals of this concept, your imagine can come up with many more ways. This list contains the methods that we use, as well as some other known methods for popping beans, as they say.

Planting the Seed in Soil is the most basic method for sprouting marijuana seeds

The most basic method is to simply plant your seeds in soil. This could be indoors or outdoors. If outdoors, the seed will not sprout until the earth is consistently warm, which will be late spring or early summer, depending on where you live.

When planting seeds indoors, you will want your soil to be at least room temperature, if not warmer. After planting, you will wait a few days for the baby seedling to poke through the soil and rear its head.

The Paper Towel Method is tried and true way for sprouting cannabis seeds

To sprout our seeds for our pheno-hunt projects, we use the paper towel method. If you’ve never used this method, it basically entails dampening a paper towel, putting the seed in the middle and folding it over. You then place the wet paper towel in some Tupperware, put a lid on it, and put it in a drawer. Come back a day or so later, and check to see if the seed has sprouted a tail.

You can also use warming pads to help nurture the process. The warming pads can speed up the sprouting process. You simply place the seeds on the pad, put it in the Tupperware or in a drawer, and wait.

The benefit of the Paper Towel method is that it is probably the most forgiving. If you are new, try this method and let us know how it went.

You can plant the seed in Rockwool and wait for it to sprout

You don’t see this method used too often, but we know of growers who drop seeds directly into rockwool cubes. The methodology would be the same as planting a seed in soil. You would make sure to water the rockwool cube, and control the environment of the room so the temperature is warm up to heat the cube and cause the tap root to sprout.

You can cause a cannabis seed to sprout by dropping it in a cup of water

Another method that is fairly simply to do is to drop your seeds into a cup of warm water. You would simply wait a day and check it frequently to see if it sprouts.

The same rules apply. You want the water and the environmental temperature to be warm to encourage the tap root to sprout.

There is a downside to this method: You must monitor and be ready to act quickly. If the tap root does sprout, it can rot if left for too long in the water. So if you use this method, monitor it daily. Once you notice the sprouted tap root, remove the seed and plant it in soil.

What to do once your cannabis seeds have sprouted: Transplanting your Seedling

Once your seeds have sprouted, it is time to transplant them into soil. This is assuming you did not initially plant your seeds in soil.

If you initially planted your seeds, you do not need to transplant unless you planted them in a very small container, like a red solo cup. In that case, you will want to transfer them to a larger pot.

What size of pot you use will depend on how large you intend on letting the plants get while in vegetative stage.

What Light Cycle should you use with sprouted cannabis seedlings

Once you have transplanted your seedlings into a new pot with soil, you will want to place them under direct lighting. For young seedlings, use a softer light, such as a fluorescent light. You do not need all the lumens in HPS or even high powered LED.

For young marijuana seedlings, use the 18/6 light schedule. This is the same light cycle you will use for the entire vegetative period. Place the plants under direct light for 18 hours, and then let them sleep with the lights off for six hours.

Now, you are ready to veg your plants. Afterwards, you will put them through a bloom cycle. For more information on those two periods, check out our articles on Understanding the Vegetative Stage and the Flowering Stage of Marijuana Growth.


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