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The cannabis seedling stage is one of the most important stages in growing your own cannabis. But seedlings can be quite difficult to grow, especially if you are a beginner.

In order for cannabis seedlings to grow into robust plants and bloom, there are a few steps that need to be followed.

Let’s start by looking at some basics of growing weed from seeds, so you can better understand why it’s so difficult for some people.


Inside that hard shell is the genetic information needed to grow into luscious big plants. When exposed to warmth and humidity, seeds can absorb water from their environment. This process is the key to life for all plants and it’s known as imbibition.

Once water enters a seed, it activates special enzymes that trigger the growth of the small white root that pops out of the seeds when germinated properly. This root pushes deeper underground in search of more water while they shoot up and out of the soil in search of light. marijuana seeds contain two cotyledons or embryonic leaves. After the cotyledons emerge, a plant will develop its first set of true leaves.

As your cannabis plants grow, they suck water out of the soil using their roots. Once they have developed their first sets of true leaves (that is, leaves with at least 5-7 fingers), they are no longer considered seedlings, but young plants in the vegetative stage.

Average duration

from 2 to 10 days

from 1 to 3 weeks

from 1 to 15 weeks

from 7 to 14 weeks



The term ‘cannabis seedling’ is an informal term used for the first stages of growth when small marijuana plants sprout after germination. A transition from a cannabis seedling to a young plant is considered an important stage in the cannabis life cycle and happened when a young plant reaches a certain age or size.

To grow a healthy seedling, you need to combine several important factors. First, you need to select quality genetics from a proven supplier. Second, you need a solid germination process with a high success rate to ensure that your seeds sprout. Third, you will need a good growing medium and containers.

What Kind of Germination Method Is Best for Cannabis Growth?

The first challenge for new growers is to germinate their cannabis seeds. Good advice can make a big difference because this is usually an area where many people make mistakes and end up with less-than-desirable results. It doesn’t matter whether you’re germinating autoflower seeds or photoperiod feminized seeds—the same methods work well for both. But which method is the best one?

Our recommendation is to germinate your cannabis seeds between two lightly moistened cotton swabs for a couple of days. Note that it is crucial to lightly spray each cotton swab 2-3 times with water mist. Wet germination conditions have a higher germination latitude than soaked germination conditions.

When choosing cannabis seeds, be sure to buy from a reputable supplier. Otherwise, your chances of getting excellent results will be slim, no matter what germination method you choose.

How Much Water Do Cannabis Seedlings Need?

Young cannabis seedlings need very little water. Small plants have a small, immature root system in the early stages of life and are unable to use high amounts of water. In addition, transpiration rates are low.

  • Overwatering

Excessive watering of cannabis seedlings is one of the most common mistakes made by less experienced growers, who often have little experience with irrigation.

It generally results in slower plant growth with smaller yields and reduced crop quality. Cannabis roots rot if the roots are left too long in damp, non-oxygenated conditions.

Overwatering can also happen when the container you’ve chosen is not of the proper size. When growing a small seedling in a big pot, excess soil can hold water for days in areas untouched by the plant’s roots. This deprives your plant of oxygen and creates a breeding ground for fungi, bacteria, and pests.

  • Underwatering

When you underwater your cannabis seedlings, their roots will struggle to find enough water to survive. The leaves wilt until the plant is watered again. This will not only kill your plant but also compromise all areas of its health. If you keep doing this, eventually it will die.

Which Containers Are Best for Cannabis Seedlings?


Airpots and plant containers made of breathable fabric have become increasingly popular in the cannabis community in recent years. These containers allow the growth of marijuana planting to proceed at a rapid pace. They are highly recommended for both growing adult plants and for cannabis seedlings. The beneficial effects of these containers include high levels of root oxygenation, which allows for a healthy cannabis root zone and thus healthy overall growth. They also help protect against root diseases and promote their healthy development.

When all the necessary conditions are present, a germinated cannabis seed can rapidly grow.

What Are the Best Nutrients to Use?

Growing cannabis seedlings can be a frustrating process, especially for beginners. If you decide to use the soil, be careful not to provide any nutrients to your plants for the first two weeks. The soil will provide sufficient nutrition for their needs.

However, some inexperienced growers assume that giving their seedlings concentrated nutrients will allow them to grow faster. Unfortunately, this is not the case. The delicate roots of the young cannabis plant cannot cope with concentrated nutrients, and their biochemistry does not need it. Excessive nutrients can cause browned ‘burnt’ leaf tips, stunted growth, and even kill a cannabis seedling.

Hydroponics growers frequently use dilute specialty nutrient solutions to feed their plants. This is done with great caution, as even these very dilute solutions can be too much for young seedlings.

Which Type of Soil Is Better to Use?

Yes, it is important to start cannabis seedlings with a healthy soil mix. Often, growers purchase a “light mix” of soil specially designed for smaller plants with lower nutritional needs than mature plants. Some growers also add perlite or coconut fiber to the soil to increase aeration.

You can opt for a different type of soil when it comes time to transplant it, choosing a soil richer in minerals and nutrients more suitable for the next stage of growth.

What Is the Ideal Temperature/Mumidity for Seedlings?

  • Temperature

When growing cannabis plants indoors, be sure to provide a stable temperature of around 23-25°C. If these temperatures get too hot, your seedlings may have difficulty absorbing enough water through their roots and may wither. If the temperatures are too cold, the growth is reduced and eventually stops.

  • Relative humidity

For humidity, cannabis seedlings can tolerate high levels of about 60% or 70%. This is useful if you are growing cuttings or seedlings with underdeveloped root systems. However, high humidity levels like these cannot be easily tolerated by mature plants in full bloom where moisture can cause mold/bud rot.

How Much Light Should Cannabis Seedlings Receive?


Cannabis seedlings do not need a lot of light. A T5 fluorescent luminaire will provide about 100-300 μmol / m² / s of light, which will be enough for most seedlings.

If you decide to use CFL lighting fixtures for optimal results, it is important that you check manufacturers’ guidelines on suspension heights, aiming for PPFD levels of 100-300.

The indoor cannabis seedling light program typically uses 18 hours of daily light, whether you’re growing autoflowering seeds or photoperiodic feminized seeds, and some growers use 20 hours or even 24 hours.

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For outdoor growers, the seedling stage is an obstacle that they must overcome. Outdoor growers have three options for dealing with this challenge:

  1. It is advisable to keep your seedlings under CFL lights in the house for the first two weeks to protect them from external elements.
  2. Alternatively, you can keep your seedlings outside during the day and move them indoors at night. This way, they won’t get too cold or wet, and you can protect them from rain and other inclement weather.
  3. Finally, you can keep your seedlings outdoors in a greenhouse, a propagator, or polytunnel until they are ready for planting in the garden. This way you can control humidity and temperature.

How Long Does the Cannabis Seedling Stage Last?

How long does a cannabis seedling stay in its seedling stage? There is no clear answer, and opinions vary from grower to grower. But most often, the first two weeks after germination is regarded as the cannabis seedling stage.

  • Transitioning to the vegetative stage

Transplant the seedlings into their new pots and give them 3 to 7 days to regularize. Transplanting is a stressful process, and your plants need some time to recover from it. If you feed your plants too early after they’ve been moved, they may not absorb all of their nutrients from their new soil. This can cause problems later on (such as nutrient blockage).

Can You Speed Up the Germination Process?

When growers try to speed up the germination process, they often end up killing their plants. For example, it is not recommended to sand-paper seeds in an attempt to reduce the shell thickness. Nor is it recommended that you force off the seed coat during germination; instead, just be patient and allow the genetics to do their job

Transplant Cannabis Seedlings Into a Bigger Pot

When growing photoperiodic feminized seeds, many growers gradually move their cannabis seedlings into progressively larger containers. A general rule of thumb is to put the seedling in a larger pot once its leaves have the same diameter as the container. So when the leaves protrude from the edges of your pot, consider transplanting your cannabis seedling into a larger pot.

If you decide to grow autoflowering seeds, you need to consider that your cannabis plant has a fixed life cycle and you may not have enough time for your plant to adapt to the new post-transplant conditions. To avoid this, many growers place the germinated cannabis seedling directly into its final cultivation container.

Can You Determine Whether a Cannabis Seedling Is Male or Female?

It is not possible to identify female cannabis plant seedlings until they are several weeks older and mature enough to have shown some male or female pre-flowers.


Cannabis Seedlings damping off
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Cannabis seedlings stretched, image source:
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Problems with cannabis seedlings can be an irritating time for inexperienced growers. Without a doubt, prevention is better than a cure. That means starting with top-quality marijuana seeds, a reliable germination method, and a cultivation method that you feel confident with. If you should experience problems, the following information may be useful to you.

Identifying Healthy vs Unhealthy Seedlings

A marijuana plant with yellow or discolored leaves can be unhealthy. The seedling may not even grow. An experienced grower would probably notice these problems, but to the untrained eye, it may seem healthy. The problems could come from environmental sources such as poor nutrition, lighting, temperatures, parasites, or incorrect PH.

Seedling Not Growing (or Stops Growing)

If your seedling has stopped growing, it’s a sign that you need to check the basics and make sure the cannabis seedling doesn’t have water-filled roots. Check the drainage holes that allow excess water to drain and place your cannabis seedling in cool conditions so that it can grow slowly and develop properly. Low temperatures can also be a cause for slowing growth.

Seedlings Stretch a Lot

The seedlings stretch too much when they are looking for light. That is why the stems sometimes look long and thin, or even weak. You can try to increase light levels by reducing the height of your lamp. A light of slightly higher intensity can limit this elongation; support your cannabis seedling with a stick until it has enough strength to sustain itself.

Pay Attention to the Cannabis Seedling Leaves

CANNABIS SEEDLING STAGE TIPS -cannabis seedling leaves curling problem and yellowing

Cannabis seedlings leaves curling up

If you see a seedling with the leaves curling up, the cause could be heat stress, probably caused by your HPS grow lights. When you grow marijuana, aim for stable temperatures of 23-25ºC. Remember that cannabis seedlings do not require bright light levels or bright lights until they are older.

Cannabis seedlings leaves curling down

If your seedling shows leaves curling, it’s a good sign that signals an excess of more nutrients or minerals. Nitrogen toxicity is a typical cause of this symptom.

Other factors can be the cause, including overwatering and underwatering. An unhealthy root structure will not allow the plant to absorb the moisture and this can also cause leaves to curl down. If you are a soil grower with a root-bound plant, expect to see issues such as curling leaves and an unhealthy appearance. If you are a hydroponic grower with cannabis root rot problems, you are likely to see issues until you remove the pathogens.

Pests, including Russet mites, broad mites, and Fungus gnats, can also damage your plants, causing leaves to droop or curl down. The best advice is to prevent issues before they happen by cleaning off any pests from your location.

Cannabis seedlings yellowing

Yellowing leaves on seedlings can be a warning sign that something isn’t right. It could be overwatering or too much light (“light burn”), or a pest infestation. If you see that a plant has a tangled mass of white roots at the bottom of its pot, it may be a sign that it was root bound.

Another cause could be nitrogen deficiency. This is often caused by poor soil, but it can also be caused by deficiencies in other nutrients. If this is the case, a light feed with nitrogen-rich nutrients can help.

When to Drop a Sick Cannabis Seedling

When you’ve exhausted all other possibilities, it may be time to give up your sick cannabis seedling. Sometimes, a plant’s energy levels are so depleted that it simply is not possible to recover from poor conditions. At that point, you may want to consider pulling out your seed collection again and selecting a new seed for germination.


HOW TO PREVENT PESTS AND BUGS on cannabis plants
Pests and Bugs that affects the marijuana plant

Having a clean environment around the seedlings is essential to prevent pests and sores from destroying them. Avoid excessive watering and learn to recognize common cannabis pests so you can spot and treat them in time. Some common pests to watch out for include:

Fungus gnats: These small black flies lay their larvae in wet loam and feed on your plants.

• Leaf miners: These small winged insects leave irregularly shaped spots on healthy leaves that may look like a trail of snails.

Spider mites: Spider Mites are tiny insects Black or red in color, belonging to the family of mites. They live on the underside of the leaves where they turn protective silk nets, piercing plant cells to feed. Spider mites love hot and dry conditions.

• Pythium and Fusarium: Pythium and Fusarium are pathogens that cause serious diseases in agriculture crops. They can cause damping-off of seeds, root rots, and crown rots of older plants. These fungi are hard to spot, but white spots on wet topsoil can be an early sign of their presence.

• White powdery mildew: Powdery mildew is a fungal disease that can affect your cannabis plants.. When the fungus takes over, a layer of mold comprising many spores is formed through the top of the leaves. These spores are then transported to other plants by the wind. Powdery mildew can slow the growth of the plant, and if the infection is severe enough, it will reduce the yield and last quality of your crop.

To summarize: Cannabis Germination Stage

By using quality marijuana seeds and having a good germination method alongside a stable grow room environment, you should be able to produce healthy seedlings without too much effort. Where possible, keep working towards optimizing your grow room conditions as much as possible and enjoy watching your cannabis seedlings develop into top-quality harvest-ready plants!

That’s all for our article Cannabis Seedling Stages Tips and Tricks. If you have any questions or if you just want to know more about marijuana growth, do not hesitate to contact us on our social media, and subscribe to our email to receive new updates! We will do our best to help you!

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