Topping cannabis: Everything you need to know

Adam Parsons

Cannabis Journalist & Staff Writer at Zamnesia

Adam Parsons

Last updated: 13 October 2025

Want bigger, bushier plants with more bud sites? Topping might be your new favourite grow technique. This simple method involves cutting the main stem of your cannabis plant to encourage lateral growth, resulting in stronger branches and more potential bud sites. For beginner and intermediate growers, learning how to top a weed plant is one of the easiest ways to boost yields without expensive equipment. In this guide, we'll cover everything you need to know about topping cannabis plants, from when to do it and how many nodes are needed before topping, to the differences between topping autoflowers and photoperiods, plus plenty of aftercare tips to keep your plants thriving.

What is topping cannabis?

Topping cannabis is a training technique in which growers cut off the very tip of the main stem. By removing this dominant growth point, the plant's natural growth hormone distribution changes, redirecting energy into the lower branches. Instead of stretching upward with a single central cola, the cannabis plant develops two main stems and exhibits bushier, lateral growth.

For beginner growers, topping may seem drastic, but it's actually one of the most effective ways to control plant shape and maximise light exposure across the canopy. The result? More bud sites, stronger branches, and healthier and more productive plants.

Does topping really increase yield?

Yes, topping cannabis plants can significantly increase yields when done correctly. The plant grows a wider, more balanced canopy by creating multiple main stems. This allows light and airflow to reach more bud sites, reducing the risk of mould while encouraging denser flower development.

The benefits of topping include:

• Increased bud sites: More main stems = more colas.
• Even canopy: Prevents one tall cola from overshadowing lower branches.
• Improved airflow and light penetration: Keeps the plant healthy and maximises photosynthesis.
• Better indoor space management: Ideal for small grow tents where vertical height is limited.

However, topping is not a magic bullet. It initially stresses plants, and recovery time is needed. If done too early or too often, it can slow growth instead of boosting it. That's why understanding how many nodes to wait for before topping, and choosing the right moment, is critical for success.

When to top cannabis

The best time to top cannabis is during the vegetative stage. Aim to top when your specimens are about 15–30 cm tall with at least 4–6 nodes (the point at which branches meet the main stem). Most growers find topping above the 5th node offers the best balance of strength and recovery. Waiting until this point of development allows plants to establish strong root systems and ensures they have plenty of time to recover and branch out before flowering. Topping too early can stunt growth, while waiting too long may reduce its overall effectiveness.

How to top a weed plant

Now that you know when to top cannabis, let's take a look at how to do it correctly. The process is simple, but precision and cleanliness are key. With the right equipment and a steady hand, you can safely top your plant and set it up for bigger yields.

Equipment

Before you begin, make sure you have the right tools on hand. Using clean, sharp equipment helps prevent infection and ensures a smooth cut that heals quickly. A sharp pair of Professional Pruning Shears is essential for making clean cuts that heal quickly, while Powder Free Nitrile Gloves or Sterile Gloves help protect your plants from any kind of contamination. It's equally important to keep your equipment clean. Always wipe your shears with alcohol wipes or another sterilising solution before each cut to minimise the risk of infection.

Professional Pruning Shears

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Professional Pruning Shears

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Instructions (step-by-step)

Topping cannabis is simple, but it requires careful timing and precision. Follow these step-by-step instructions to ensure a clean cut and a smooth recovery:

1. Wait for 4-6 nodes: Ensure your cannabis plant is in the vegetative stage, healthy, and tall enough to handle topping.
2. Locate the cut: Find the main stem above the 4th or 5th node. This is the best spot for topping to encourage strong lateral growth.
3. Sterilise your tools: Clean your shears and put on gloves.
4. Make the cut: Snip the main stem with a sharp tool cleanly just above the chosen node to avoid crushing or tearing.
5. Let the plant recover: Within a few days, two new shoots will form where the main stem was topped, setting the stage for a bushier structure with more bud sites.

As a top tip, always cut once, cleanly, and avoid handling the fresh wound to prevent stress or infection.

Topping autoflowers vs photoperiod plants

Topping works best with photoperiod cannabis plants, which have a longer vegetative phase and plenty of time to recover before flowering. Autoflowers, however, grow on a fixed genetic timetable. Their short life cycle means that any stress, including topping, can slow growth and reduce yields instead of boosting them.

Risk factors and timing issues for autos

Autoflowering strains usually transition to bloom within just a few weeks after sprouting, leaving little room for recovery. Topping autoflowers too early can stunt development, while waiting too long may leave them without enough time to bounce back. For this reason, many growers choose to avoid topping autoflowers altogether, or attempt it only on very vigorous strains with strong early growth.

Alternative training techniques

Instead of topping, autoflowers usually respond better to low-stress training (LST), which gently bends and ties down branches to create an even canopy without slowing growth. This technique is safer and less stressful for the plant, but it still helps maximise light exposure and bud production. For more information, check out our full guide on LST techniques.

Topping vs not topping

The main difference between topping and not topping cannabis lies in how the plant grows and ultimately yields. A topped plant develops a bushier shape with multiple main colas, which can increase overall yield by making better use of light and space. In contrast, an untopped plant grows in a Christmas tree-like shape with a single large central cola, meaning less light reaches the lower branches and buds. However, topping does introduce stress, and plants need time to recover before resuming vigorous growth. Untopped plants will avoid this stress, growing faster and more naturally, but often at the cost of smaller harvests.

Common mistakes when topping cannabis

Topping cannabis is simple in principle, but there are a few common pitfalls that can reduce its effectiveness or even harm your plants. Being aware of these risks will help you avoid setbacks and get the best results possible.

Topping too early or too late

Timing is everything. Topping too early, before plants have 4–6 healthy nodes, can stunt growth and leave plants struggling to recover. On the other hand, topping too late when plants are already tall or close to flowering limits the benefits of the technique and can stress plants unnecessarily.

Damaging the main stem

The main stem is the plant's lifeline, and a rough or uneven cut can cause tearing, infection, or slow recovery. As mentioned, always use sharp, sterilised tools to make a clean cut above the chosen node. Avoid crushing the tissue or cutting too low, which can damage vital growth points.

Poor recovery support

After topping, cannabis plants need the right conditions to recover. Without adequate light, airflow, nutrients, and water, recovery will be slow and yields may suffer. Giving plants a stable environment and a few days of reduced stress (no additional training or pruning) helps them bounce back stronger.

Post-topping recovery and plant care

After topping, your cannabis plant will need some time and the right conditions to recover. This short recovery window is crucial for encouraging new growth and preventing unnecessary stress.

Nutrient support

Topped plants benefit from a steady supply of nutrients to fuel recovery and new branch development. A balanced vegetative feed rich in nitrogen, calcium, and magnesium will help support vigorous regrowth. Avoid overfeeding, as stressed plants are more sensitive to nutrient burn. Instead, stick to moderate, consistent doses.

Environmental conditions

Healthy recovery also depends on stable growing conditions. Keep your plants in a warm, well-ventilated environment with plenty of light spread evenly across the canopy. Good airflow reduces the risk of mould and encourages strong branch formation, while consistent watering ensures the plant has the resources it needs to heal. For best results, avoid adding extra stress and hold off on other training techniques for several days until the plant shows clear signs of recovery.

Can you top cannabis multiple times?

Yes, you can top cannabis multiple times, but it's essential to space out each cut and keep plants in the vegetative stage, by keeping indoor lighting above 12/12 for photoperiods, long enough for them to recover. Most growers recommend allowing 1–2 weeks between topping applications to give plants time to bounce back. Generally, 2–3 topping sessions are effective for boosting yields, with 3–5 being the upper practical limit before benefits plateau or stress accumulates. Stop topping at least a couple of weeks before the flowering stage, so your plant can shift energy toward bud production instead of recovery. For more information on handy cannabis trimming techniques and tips, check out our full guide.

Is topping cannabis worth it?

For most growers, the answer is yes. Topping cannabis plants is a proven way to encourage bushier growth, create more bud sites, and ultimately increase yields, especially with photoperiod strains. While it requires careful timing and some recovery, the benefits often outweigh the drawbacks. If you're ready to try topping, start with healthy plants and don't forget to give them the proper aftercare. For those about to make their first steps into growing, check out our wide range of cannabis seeds, or if you're a little more experienced, explore advanced training techniques like mainlining to take your harvests even further.