Cannabis Seedling Problems: How to Handle Them

cannabis seedling problems

When it comes to cannabis, life will always begin right after the germination. They become extremely vulnerable to different common cannabis seedling problems at this stage. They don’t have enough power and resilience against diseases. Likewise, just one mistake can already put their life at stake.

As a grower, you need to be aware and extra careful about the possible problems that may occur when taking care of cannabis seedlings. Likewise, you need to keep them safe from significant damages the diseases can cause. 

How Do Healthy Cannabis Seedlings Look Like?

Cannabis seedlings are young plants that have sprouted from seeds. They are indeed extremely vulnerable and sensitive, considering that they are just on their way to maturity. If the cannabis seeds split, a white tendril will come out. This white tendril will dig down to the soil and will eventually develop as the plant’s root. 

When the root has been fully developed, the plant will continuously grow, developing its first 2 round leaves called cotyledons. These little leaves are formed deep within the seed and will just come out when the seed sprouts. As the cotyledon appears, the real leaves of a cannabis plant will begin to develop from the middle. The leaves will continuously grow until they achieve the actual shape and look of mature marijuana leaves. 

Common Seedling Problems to Fix and Avoid

It is a must to understand and learn how to fix the common seedling issues. This is also to learn how you can avoid them once and for all. If you’re a novice cannabis grower, it might be difficult to avoid making mistakes, but you need to learn. Here are the common preventable cannabis seedling issues, how to fix them, and what to do to avoid them:

1. Overwatering

If your soil medium is usually moist and the leaves die immediately, then the problem could be overwatering. Nonetheless, this particular phenomenon is preventable since cannabis plants require oxygen to grow continuously. Usually, overwatering can lead to oxygen deprivation that can be life-threatening to plants.

You don’t need to water cannabis seedlings often because they are still small and developing. They act like kids as they consume just a small amount of water and nutrients to support their development. Hence, you must water them only if the soil dries completely.

Nevertheless, you need to control and adjust your watering cycle as soon as you detected this symptom. Be sure to observe and note any physical changes you see in the plants throughout this process. 

2. Underwatering

It does not have much difference from overwatering. It is a must for cannabis seedlings to get sufficient water every day to ensure their growth. If you water them, it is normal for them to lose some moisture through transpiration, the breathing process in plants. 

Though water is indeed necessary for their normal growth, cannabis plants take in just some water that they use to ensure healthy growth and metabolism. The excess water will then evaporate through the stems, leaves, and flowers. The leaves will release the moisture over the stomata that also takes in water once it opens. 

It is best to understand the symptoms of underwatering that is usually mistakenly identified as overwatering. When you are sure the problem is not overwatering, watch out for these symptoms to find out if underwatering is your issue:

  • The plants look lifeless
  • Leaves are drooping
  • The leaves are thin and papery
  • The leaves are also changing their color to yellow
  • The soil is extremely dry

Detecting the issue can sometimes confuse you as underwatering tend to have similar symptoms with overwatering and even nutritional deficiencies. One quick way to identify and confirm the issue is to observe your plants after you water them. Underwatering is the issue if they quickly perk up.

Underwatering is easy to fix. Just be sure you water your plants as often as possible. Even when the plants show the symptoms of underwatering, be sure not to water them a lot that can worsen the problem instead of getting it fixed. 

3. Nutrient Deficiencies

Nutrient deficiencies are a prime issue for cannabis seedlings, too. Several nutrition issues include insufficient, excessive, and giving the wrong type. Knowing the specific nutritional needs of your seedlings and being knowledgeable about the symptoms of common seedling issues is important in keeping your plants protected. 

If cannabis seeds don’t receive sufficient nutrients, they become more susceptible to shock. Given that they are already vulnerable, experiencing shock will extremely cause them to wither. Outlined below are some ideas into a few of the symptoms of nutrient issues:

  • The leaves have turned into yellow
  • The leaves got their tips darkened
  • Yellow and brown spots are also visible on the leaves
  • The plant stopped growing
  • The leaves curled

Insufficient nitrogen is among the most common forms of nutrient deficiencies in cannabis seedlings. Nitrogen is important in each phase of plant development.

4. Lighting Problems

Cannabis plants need light to thrive. Without proper lighting, they will struggle to perform and undergo the process of photosynthesis, which is a crucial process associated with creating food energy. Too little lighting is as dangerous as excessive lighting. You might notice these symptoms if there are issues with the lighting installed in your grow room:

  • Burned leaves
  • Shriveled leaves
  • Leggy plants
  • Big gaps between the nodes

It’s quick to solve lighting issues in many cases. If the lighting is quite close to plants causing them to incur burns, just move the lighting far away from them. If not all, the plants receive ample lighting, then move the light a little closer. Seedlings will often react quickly once you fix these lighting issues.

5. Excess Heat

As marijuana plants need warmth, excess heat could be dangerous to the growth of your seedlings. To make sure your seedlings will grow well and less susceptible to symptoms of increased temperature, keep the temperature inside the grow room anywhere between 70-77 degrees Fahrenheit.

Anything more than the given temperature range is sure to cause cannabis seedlings to experience heat shock. It will cause the curling of the leaves that look like a taco or boat. Likewise, it is important to avoid putting the lighting too close to seedlings to prevent burn. 


The common cannabis seedling problems are easy to fix and highly preventable. Don’t fret if you made a mistake in taking care of marijuana seedlings. It happens, but you should learn from the experience. 

After learning from experience, you can buy cannabis seeds to add to improve the number of your produce.