Top 5 Cannabis Growing Problems & Quick Fixes for Beginners

Introduction

Growing cannabis can be an incredibly rewarding hobby, but it also comes with its fair share of surprises. Beginners often run into recurring issues like overwatering, nutrient deficiencies, or light-related stress. Fear not—most problems can be addressed quickly once you know the symptoms, causes, and correct fixes. In this guide, we’ll walk you through the top five cannabis growing problems that beginners face and provide quick solutions so you can keep your plants healthy and thriving.

Possible Causes of Overwatering

Cause 1 – Too Frequent Watering

Watering too often keeps the soil constantly saturated, starving roots of oxygen.
Symptoms: Drooping, yellowing leaves that remain limp even though the soil is wet, slow growth, a musty or sour smell.

Cause 2 – Poor Drainage

Even if your watering schedule is reasonable, soil or containers without sufficient drainage can lead to waterlogged roots.
Symptoms: Very similar to over-frequent watering, plus heavy, compacted soil that stays wet for days.

Cause 3 – Overly Water-Retentive Medium

Some mediums, particularly those heavy in peat moss or without added perlite, can retain too much water.
Symptoms: Consistently wet soil, very slow plant growth despite careful watering frequency.

How to Fix Overwatering

Solution for Cause 1 – Stop Watering and Adjust Schedule

First, give the soil time to dry out thoroughly. Avoid watering until the top inch of soil is dry to the touch. You can use a finger test or a moisture meter to be sure. Learn more about proper watering.

Solution for Cause 2 – Improve Drainage

Ensure your containers have sufficient drainage holes and consider amending heavy soil with perlite or coco coir to enhance aeration. Explore soil improvement.

Solution for Cause 3 – Repot in Better Medium

If your current medium is too water-retentive, transplant into a mix that offers better drainage. Fabric pots or Air-Pots can also help. See container options.

How to Prevent Overwatering in the Future

• Use well-draining soil and containers with sufficient drainage holes.
• Water thoroughly but less frequently, ensuring the topsoil has dried out.
• Monitor moisture levels with a meter or the finger test. Essential watering tools.

Possible Causes of Underwatering

Cause 1 – Infrequent Watering

If you wait too long between waterings, the plant’s roots can dry out, leading to dehydration.
Symptoms: Wilting, dry or brittle leaves, drooping branches, and slowed growth.

Cause 2 – Insufficient Water Volume

Sometimes you’re watering often enough but not providing enough water to saturate the entire root zone.
Symptoms: Dry patches in the soil, uneven growth, wilting even after watering if the root zone isn’t fully reached.

How to Fix Underwatering

Solution 1 – Water Thoroughly and Adjust Schedule

When watering, aim for a bit of runoff to ensure the entire root zone is moistened. Don’t just sprinkle the top. Review proper watering techniques.

Solution 2 – Improve Water Retention

If your medium dries out too quickly, consider mixing in vermiculite or coco coir. This can help maintain moisture. Learn more here.

How to Prevent Underwatering in the Future

• Establish a consistent watering schedule based on plant size and environment.
• Check soil moisture levels often, especially during hot or dry weather. Explore watering tools.

Possible Causes of Nutrient Deficiencies

Cause 1 – Insufficient Nutrients in Soil/Solution

Over time, plants deplete the nutrients available in their medium. Without replenishment, deficiencies arise.
Symptoms: Vary based on specific nutrients (yellow leaves, spotting, stunted growth, etc.).

Cause 2 – pH Imbalance (Nutrient Lockout)

Even if your feeding schedule is perfect, a pH outside the acceptable range can lock out nutrients.
Symptoms: Deficiency-like signs despite adequate feeding.

How to Fix Nutrient Deficiencies

Solution 1 – Identify Deficiency and Adjust Nutrients

Observe symptoms carefully or use a deficiency chart to pinpoint the missing nutrient. Then, adjust your nutrient solution or soil amendments accordingly.

Solution 2 – Check and Correct pH

Test the soil runoff or hydro solution; aim for 6.0–7.0 in soil and 5.5–6.5 in hydro. Adjust if needed.

How to Prevent Nutrient Deficiencies in Future

• Use cannabis-specific nutrients and follow a feeding schedule. Check feeding schedules.
• Monitor pH regularly to ensure nutrients remain available.

Possible Causes of Nutrient Burn

Cause – Overfeeding Nutrients

Too many nutrients can overwhelm your plants, leading to toxicity.
Symptoms: Burnt or brown leaf tips, curled leaves, severe yellowing, stunted growth.

How to Fix Nutrient Burn

Solution – Flush and Reduce Nutrient Strength

Flush your medium with pH-balanced water to remove built-up salts. Then, use a gentler nutrient mix for subsequent feedings. Learn to flush correctly.

How to Prevent Nutrient Burn in Future

• Begin feeding at lower-than-recommended doses and gradually increase.
• Regularly monitor runoff EC to detect salt buildup. Check EC management.

Possible Causes of Light Stress

Cause 1 – Light Burn (Too Intense/Close)

High-intensity lamps placed too close can bleach or scorch the top leaves.
Symptoms: Bleached patches, brown leaf edges, leaf tips curling upward.

Cause 2 – Insufficient Light (Stretching)

If your plants receive too little light, they may stretch toward the source.
Symptoms: Spindly, elongated stems, weak growth, leaves spaced far apart on the stem.

How to Fix Light Stress

Solution for Light Burn – Adjust Light Distance/Intensity

If leaves are bleaching or curling at the top, move the lights further away or reduce intensity. Learn more about light burn.

Solution for Stretching – Increase Light Intensity/Closer

Place lights closer or use more powerful lamps to ensure adequate light levels. Master seedling lighting.

How to Prevent Light Stress in Future

• Measure light intensity (PAR) and place lamps at the recommended distance.
• Gradually acclimate plants to more intense light, especially after switching to higher-watt lamps.

Conclusion: Troubleshooting for Success

Even the most experienced growers run into problems, but the key is recognizing the signs early and taking swift action. By focusing on water management, nutrient balance, and proper lighting, you can prevent many of the common pitfalls that plague beginner growers. And if a problem does arise, use the tips in this guide to bring your plants back to good health and stay on track for a successful harvest.

Remember, a healthy grow is about being proactive—monitoring conditions and adjusting as needed. With each issue you resolve, you’ll gain valuable experience and confidence in your cultivation skills.

Frequently Asked Questions (FAQ)