Get Leafist articles and new strain alerts in your inbox

Common Issues When Growing Marijuana

When growing marijuana plants, you really have to pay attention. These plants are finicky and must be cared for properly. The good thing about marijuana plants is that they will show external signs of distress or trouble, which you should attend to immediately. This guide will help you understand several of the most common grow issues and how to fix it.


Poor Quality Seeds

If you start with a poor quality seed, such as one that is small or has a white shell, you may be in for some issues when growing. Always pick the biggest, hardest and darkest green seed you can find, as it is likely to perform the best. It is important to germinate your seeds for 72 hours in plain water, kept in a dark, dry area, before introducing it to peat moss and soil mixtures.


Root Issues

When your plants begin to grow, keep an eye on the root bases. If your roots curl up around the root bulb or bottom of the plant, they are likely to choke each other. This can cause the plant to experience deficiencies that can be a factor in the death of the plant.

If the roots of your marijuana plant are slimy or smell rotten, your plant is lacking oxygen. A lack of oxygen leads to growth issues and reduces the quality of the end product.

When your first transplant is scheduled, examine the root base and make sure that the roots are strong, not intertwined too much and are free from mold. Mold occurring in the roots is a nearly impossible issue to overcome, as you may have to trim some of the roots away to correct the issue. This may slightly stunt the growth of your marijuana plant.

If the roots are curling over the sides of the container, you should transplant your plant as soon as possible. Your plant does not have enough room to grow, which can lead to stunted growth or lowered production.


Stem Issues

It is important to pay attention to your stems. This is what holds your plants and flowers up. Stems are responsible for providing nutrition and water to the flower. Stems are mostly water. Although thick stems aren’t desirable to those purchasing marijuana legally, it’s actually a good thing. A good, thick stem tells you that the plant has been properly fed and watered, and that it has the best chance for increased potency.

Thin stems can mean that your plant is not getting enough light. Adjust the lighting in the space or add more. It is also a good idea to make sure the plant is properly trimmed so that larger leaves are not shadowing over flowers.

Marijuana plants require moving air to help stimulate the stems. Make sure your grow space has moving air, such as a proper circulation system created from fans.

What do you do if you notice a broken stem? Don’t panic, really – it’s fixable in most cases. You really can tape a broken stem back together, but make sure you attach the broken stem to a stake so that it can be secured. Now, if your stem is completely severed, there’s really no way to save it. Partial breaks are salvageable in most cases.


Vitamin/Nutrient Deficiencies

If your marijuana plant is not getting enough vitamins or nutrients, your leaves are likely to be smaller, thinner and light green in color. Overfed plants can experience nutrient burn. This is when the concentration of nutrients and/or fertilizer is too high. You will notice brown tips on the edges of your leaves if the nutrient concentration is too high.


Improper pH Levels

If your pH levels are even slightly off, it can negatively affect your marijuana plant. You will notice pH balance issues in the leaves of your plant. When the levels are too low or too high, nutrients can be blocked from getting to the leaves and blowers of your plant.

Signs of improper pH levels include:

  •  Tan leaves
  •  Yellow spots
  •  Light brown spots

How do you maintain proper pH levels? Check your pH levels twice a day. Do not add more fertilizer to the plant as this can completely kill it. Instead, check your soil as that is likely where your problem lies. If your soil is not the proper mixture, it will either create hot spots or not allow the plant to take in the proper amount of nutrition.

If your pH levels are extremely off, start a flushing process to help even the balance. Flushing should be done with plain, distilled or spring water that is free of chemicals. You should monitor pH levels throughout the flushing process as well.


Nitrogen Imbalances

Nitrogen imbalances can cause a host of issues for your marijuana plant. If your plant is not getting enough nitrogen, the leaves will begin to turn yellow starting at the bottom of the plant. This will spread upward, and can eventually reach the top of the plant. The deficiency can spread to the whole plant rather quickly.

Note: Yellowing of the leaves can also be an over-fertilization issue. Do not add extra fertilizer to correct the issue.

To determine whether you have a nitrogen deficiency or over-fertilization problem, flush the plant with fresh clean water. If you notice an improvement in the plant, then it is a fertilization issue.

If your soil tests determine that your nutrient salt levels are too high, add more nitrogen to your soil. Now, if you notice that leaves are turning yellow during the flowering stages, this may be completely normal. You can add more nitrogen to the fertilizer mix toward the end of the growing process to slow down the yellowing and will not affect the quality of the marijuana.


Nitrogen Toxicity

Nitrogen toxicity, or excessive levels of nitrogen in marijuana plants, can be detrimental. You may experience your leaves curling, forming what looks like an eagle claw. Nitrogen claw can be remedied by transplanting your plant into a properly mixed soil/nitrogen/fertilizer blend with a proper amount of peat moss. It may take several days to decrease the toxicity but your plant is salvageable if the leaves have not turned brown and started falling off.

Symptoms of nitrogen toxicity in marijuana plants includes:

  • Stunted growth
  • Frequent diseases
  • Frequent pest attacks
  • More susceptible to frost damage
  • Failure to grow flowers

It is best if you catch the toxicity issue prior to mature growth stage. To help nitrogen toxicity, use brown organic matter like straw or fall leaves, as their carbon levels are high. Add this to the soil by mixing it in like mulch.

Be careful about over-watering as this can cause root rot or plant fungal diseases. Do not increase nutrient levels to remedy nitrogen claw, this will cause additional issues within you plant such as plant death or stunted flower production. Nitrogen toxicity generally results in lower yields.


Gnats or Insect Pests

How do you keep gnats and insects off of your marijuana plants? The best option to ensure that gnats and other creatures stay off of your marijuana plants is to use a diluted seaweed solution. Not only does this help protect your plant, if grown outdoors, from frost damage but it also helps the plant become resistant to gnats and other potentially harmful pests.

If you notice that there are little fruit fly-like or gnat-like bugs around your plant, follow the instructions on seaweed solution, such as BioWeed, to correct the issue. You can hang fly strips or fly tape in the room to catch some of the pests too.


Loose Buds

If your marijuana buds are not looking very tight, it could be a sign of nitrogen toxicity. Loose buds are also less potent and are harsher to smoke. The main reasons for loose buds is improper lighting, improper room temperature and nutrient imbalances. You may also have an airflow issue or root-based problem.

Use lighting options that emit yellow, red or orange light as your plant will respond well and produce tighter buds. The use of reflective material within your grow space will assist in redirecting light toward your plants so they get the proper amount of light. Light causes heat, so you also need to take into consideration the temperature of the room when the lights are on. Use fans to help regulate the temperature in the room.


Potential Mold

Mold can occur anywhere on your marijuana plant. If you notice mold on your buds, you should dispose of the affected flowers and examine the rest of your plant. Diagnosing a mold issue, however, is difficult because it presents as fluffy white material over the bud, which is commonly confused as trichomes. Use a magnifying glass to take a closer look at the white, fluffy material over the bud to determine if it is mold or trichomes.

Mold is common where humidity is too high. Adjust the climate in your grow room and keep a close eye on your plant. Your entire plant may not be affected. Promptly remove the molded parts of the plant but do not give the plant extra nutrients or “food” as it can just cause more damage.


Closing Tips

When you are just learning to grow, it is a good idea to start with just one plant. Growing marijuana is a science and your first time out of the gate is likely to experience some bumps along the way. Sativa strains are much harder to grow, so if you are a newcomer to marijuana growing, it is ideal to master indica and hybrid strains first.

More in-depth guides for growing marijuana successfully will soon be available here at Leafist. Visit our strain list and blog to help determine what strain to help you decide the proper strain to grow for your needs.

In case you missed it

See More ›

How to Enjoy Marijuana Edibles – Managing Dosages How to Enjoy Marijuana Edibles – Managing Dosages
Leafist Weekly Cannabis News Roundup – Issue 1 Leafist Weekly Cannabis News Roundup – Issue 1
9 States Have Voted on Marijuana Measures – Here’s What Happened 9 States Have Voted on Marijuana Measures – Here’s What Happened
New Cannabis Growers: Best Strains for the Best Results New Cannabis Growers: Best Strains for the Best Results

😗💨 Weekly Rollup

Get a weekly digest of news and strain information. Delivered every Friday.