Germinating Cannabis Seeds

How to germinate cannabis seeds?

So, you've got seeds. Now what? Whether you are breeding your own marijuana plants or just starting your garden indoors, the first step to growing a healthy plant is germinating the seeds. Germination is the process in which a plant sprouts from a seed. Cannabis seeds need proper conditions to germinate.

If you are using seeds from a reputable seed bank, germination will be relatively simple, provided that you have the right environment. Marijuana seeds are hardy but require a moist warm environment to germinate successfully. This blog will walk through the steps of our seed germination protocol and make it easier for beginners to follow along.

Step 1: Soak in 3mL/L hypochlorous acid water solution for 15 mins

Soaking is a significant step in the germination process. It helps break down the seed's outer coating and prepares it for germination.

The taproot will push through the shell easier if you have soaked your seeds in water. The best way to soak any seed is to use a 3mL/L hypochlorous acid water solution.

Step 2: Place into drained Rockwool sheets using the dibble hole

Successful germination starts with the right equipment and seeds. The most popular way of germinating cannabis seeds is the paper towel method. However, some growers prefer to use other germination methods such as Rockwool starter cubes, coco, peat pellets, or a more natural soil mix.

Start by soaking the Rockwool cubes in pH-balanced water (pH ~5.8) for about 30 minutes. This will help the cube soak up water evenly, preventing pockets of dryness that could kill your little seedling.

Once your Rockwool has been soaked and drained, take one of the sheets and cut out a hole about an inch wide in the middle using a dibble stick or similar tool. This is where you will put your seed once it's ready for sowing.

Step 3: Press seed into dibble hole down approximately 1-2cm, so that it is snugly seated into dibble

If you're planting more than one seed, make sure that you leave enough space between each one so that they all have room to grow and develop their roots. The seeds should be planted between 1-2cm apart, depending on the size of your germination tray.

Place the seed into the hole to rest snugly against the growing medium, and then gently press them over the top of the hole. Once you've done this, lightly water the seed again and leave it alone to do its thing.

Step 4: Place dome on tray vented under 100 ppfd for 3-5 days

The next step is to put the seed tray back in the germination space, with the dome on top. Remove the tape and leave it alone for 3 - 5 days to grow roots. Seeds require darkness to germinate, so keep them in darkness as long as possible. If you're going to have a hard time keeping them in total darkness, at least keep them under 100 PPFD of light

We recommend leaving them in darkness at room temperature until they start poking up through the soil, which will take around five days, depending on the strain and soil quality. Some people like to take off the dome right before the taproot comes out, but we prefer to leave them in absolute darkness for as long as possible.

Step 5: After 3-5 days, remove the dome, place under stronger light levels (200-350 ppfd)

Whenever you first germinate your cannabis seeds, it is essential to keep a close eye, as seeds can be delicate and need the right conditions to sprout. After 3-5 days, when the taproot has appeared, and the seedling has broken through the shell, it's time to take the dome off and place your seedlings under stronger light levels (200-400 ppfd).

You may also want to consider using a humidity dome at this stage. Using a grow tent, you can achieve high humidity with a humidifier for more than 24 hours. If you are not using a grow tent, place your plant under a dome for 24 hours if needed. The humidity dome should be left for 1-2 days until the first leaves have fully expanded. During this time, ensure there is enough moisture. Do not let the growing medium dry out completely, as root development is still crucial!

Step 6: Records and next steps

Record the number of each cross that successfully germinated. If a plant sprouted from seed and was damaged for another reason than outright failure to germinate, those are still counted as successful germination.

If the seed did not germinate, note the failure in your record keeping. It should be noted whether it was an actual failure or if the young seedling was damaged during transfer or destroyed by mold. Label all cups and pots with the young plant name and date planted. This will help you keep track as things grow and keep things organized.

Development of the seedling

The development of the seedling is not just limited to germination. It is a long process that goes on for several weeks after germination. Here are some more critical stages beyond the germination:


Vegetative stage

After 10-14 days of growth in the Rockwool cube, transfer your seedlings into their preferred substrate in either a 4x4 (16 plants) or 5x5 (25 plants) configuration. Grow lights should be placed at 36-42" above the tops of your plants during this vegetative stage.

When transplanting from Rockwool into a preferred substrate, it is essential to note that when the roots emerge from the seed, they are especially sensitive and should not be exposed to direct light or dehydration while being transplanted.

The plants will start to go through a growth spurt. They need more food and more light. The buds become thicker, and the leaves grow more prominent. This is the stage where most of your plants' photosynthesis occurs. The veg stage is typically 14-28 days depending on desired plant height, with 28 days being ideal for developing plant structure so that flowering can proceed without challenge. It is preferred that the plants are not topped so that normal expression of plant structure can be established.

Flowering stage

During the first few weeks of the flowering stage, it is a good idea to scout for hermaphrodite plants. Hermaphrodites are not necessarily a problem, but they can ruin your crop if allowed to pollinate themselves or neighboring female plants.

One of the most critical data collection tasks is also carried out during this stage. At every watering, or at least twice per week, you will want to be recording the size and number of your plants' leaves. This is an important metric used to determine plant health and quality, both for those who are growing for themselves and those who wish to sell their cannabis on the open market.

Assessment of quality should take place throughout the flowering stage. At this time, you can begin to make determinations about which plants will be worth keeping around and which ones have undesirable traits that you may wish to breed out in future generations.

You can use pruning techniques to promote more productive growth patterns in your plants during this time, although it is recommended that you do not prune any "underground" parts of your plant (i.e., roots).

The bottom line

The truth is, there's no right or wrong way to germinate cannabis seeds, but each method comes with its advantages and drawbacks. Either way, if you do it correctly, your chances of success will be very high. Now you know how to germinate cannabis seeds. Germinating weed seeds is an essential step in growth, and you must take your time to do it properly. If you follow the instructions and pay good attention to detail, your weed will thank you for it!