Topping cannabis clones—removing the main growing tip to force two new colas in its place—is one of the highest-return techniques available to a cannabis grower. Done at the right time on a recovered, established clone, it can double or triple the number of productive flower sites without adding a single gram of inputs. Combined with low-stress training (LST), it creates a flat, even canopy that captures light uniformly and produces significantly more weight per watt than an untrained plant.

This guide covers every major training technique for clones: topping, FIMing, LST, and supercropping. You will get a side-by-side comparison table, step-by-step instructions, and a clear timeline for when to start and when to stop training before the flip to flower.

Key Takeaways

• Do not top a clone until it has fully recovered from transplant and is actively growing—minimum 4 to 5 nodes, typically 2 to 3 weeks into vegetative growth.
• Topping produces two main colas from one; FIMing (done imprecisely) can produce three or four but with slower recovery.
• LST requires no cutting—it uses gentle bending and tying to create a horizontal canopy that maximizes light exposure to lower bud sites.
• Stop all training (topping, FIMing, supercropping) at least 2 weeks before switching to a 12/12 light schedule so the plant enters flower without open wounds.
• LST can continue safely into the first 2 to 3 weeks of flower to manage canopy height and separate colas.
• A trained clone from a reliable genetic source will consistently outperform an untrained seed-grown plant of the same variety.

Why Train Cannabis Clones at All?

An untrained cannabis plant grows in an apical dominance pattern—the main central cola dominates and suppresses lower branches through hormonal signals (primarily auxin). The result is a Christmas tree shape: one big top cola and several smaller, underdeveloped lower sites that receive little light and produce airy, lightweight buds.

Training disrupts this hierarchy. By removing or bending the dominant growing tip, you redirect the plant’s energy into multiple lower sites simultaneously. Those secondary branches develop into main colas of their own, each capable of producing a dense, well-formed flower. The canopy becomes flat and even—every bud site is at roughly the same distance from the light source.

The yield impact is significant. Growers routinely report 20% to 40% more usable dry weight from trained plants versus untrained plants in the same space, using the same light. In a tent or under a single grow light, an even canopy is the difference between using 70% of your available light and using 95% of it.

Clones have a specific advantage here over seeds: because every clone from the same mother is genetically identical, you can dial in a training strategy once and replicate it exactly across an entire canopy of plants. No guesswork about growth structure—you already know what this genetic does.

When Is a Clone Ready To Top?

Timing the first top correctly is critical. Top too early—before the clone has recovered from transplant and established itself in its new medium—and you stack two stressors on a plant that cannot handle either one well. The result is a prolonged recovery that costs you more time than the training saves.

Wait for all three of these conditions before topping:

1. Minimum 4 to 5 nodes. You need enough node count below the cut to have multiple strong lower branches that will develop into the new main colas. Topping a 2-node clone leaves you with almost nothing to work with.
2. Active growth after transplant recovery. The plant should be visibly growing—pushing new nodes, developing larger leaves—for at least 5 to 7 days before you top. A plant still recovering from transplant shock is not ready.
3. 2 to 3 weeks into vegetative growth post-transplant. Even fast-growing strains need time to build the root system that will support accelerated branching after the top. Respect this window.

If you are growing from clones purchased at IWantClones.com, you skip the propagation phase—your clone arrives rooted and ready to grow. Most growers are ready to top their IWantClones plants within 10 to 14 days of receiving them, after the clone has settled into its new medium and resumed active vegetative growth. Check out our cannabis clone growth stages guide for a week-by-week breakdown of what to expect.

Training Technique Comparison

Topping Cannabis Clones: Step-by-Step

Topping (also called “pinching” when done with fingernails, though scissors are more precise) is the act of removing the apical growing tip—the topmost shoot of the main stem—above a specific node. This causes the two lateral shoots directly below the cut to accelerate growth and become the plant’s new main colas.

What You Need

• Sharp, sterile scissors or pruning snips
• Isopropyl alcohol (70%) to sterilize your cutting tool
• Optional: cloning gel or Aloe vera to seal the cut

The Topping Process

1. Identify node count. Count up from the base of the plant. Nodes are the points on the stem where leaves and branches emerge. You want to make your cut above the 4th or 5th node for most clones. This leaves four or five sets of lateral branches below, all of which will now accelerate.
2. Sterilize your tool. Wipe your scissors with 70% isopropyl alcohol and let them dry for 30 seconds. Cannabis is remarkably susceptible to pathogens entering through cut tissue, and a sterile cut is non-negotiable.
3. Make the cut. Cut cleanly through the main stem just above the 4th or 5th node—approximately 0.5 cm above the node pair you want to keep. A clean cut at a slight angle (45 degrees) drains moisture and reduces the risk of rot at the wound site.
4. Remove the cut material. You are removing the growing tip and any small leaves attached to it above the cut. These can be discarded or, if the tip has enough stem length and is from a particularly desirable genetic, placed in cloning gel and used as a new cutting.
5. Optional: seal the cut. A thin smear of Aloe vera gel or a dilute hydrogen peroxide solution applied to the cut helps protect it from pathogens. This step is particularly useful in high-humidity grow rooms.
6. Return to normal conditions. No need to reduce light, increase humidity, or make any special adjustments after topping an established clone. The plant will pause upward growth for 3 to 5 days while it redirects energy, then the two lateral branches below the cut will visibly surge.

What Happens After Topping

In the 24 hours after a top, you will often see the plant look slightly “frozen”—no visible growth, possibly very mild drooping. This is normal. By day 2 to 3, the two lateral shoots below the cut will begin visibly elongating. By day 5 to 7, they will be clearly the plant’s dominant growth points. By day 10 to 14, a well-topped clone will have two symmetrical main branches racing upward.

At this point, you have two choices: let those two branches grow into two main colas, or top each of them again (second topping, called “manifolding” when done systematically) to create four main colas. Each additional topping adds recovery time, so plan your veg length accordingly.

FIMing: The Less-Precise Alternative

FIM stands for “F*** I Missed”—a name that accurately describes its origin as an accidental partial top that produced better results than expected. FIMing involves pinching or cutting roughly 75% to 80% of the new growth tip instead of removing it entirely. The remaining tissue initiates multiple new growing points rather than just two.

The advantage of FIMing is that it can produce three or four new colas from a single cut compared to the two from a standard top. The disadvantage is that the result is less predictable and the plant may take slightly longer to recover and express the new growth structure clearly.

How To FIM

1. Identify the newest, smallest set of leaves at the very top of the plant—the apical meristem. These are the tightly packed, immature leaves that form the growing tip.
2. Using your fingers or scissors, pinch or cut approximately 75% to 80% of this newest growth away. You should leave a small amount of tissue—roughly the lower 20% to 25% of the new shoot.
3. What you see in the aftermath looks ragged compared to a clean top. That is normal and expected. The remaining tissue will develop into three or four new growing points over the next 5 to 10 days.

FIMing is generally best suited for growers who have already mastered standard topping and want to experiment with higher cola counts, or for situations where you want to minimize stress during a critical growth window and the less-invasive cut of a FIM makes more sense than a full top.

Low-Stress Training (LST): How To Build an Even Canopy

Low-stress training (LST) is a non-cutting technique that shapes the plant’s structure by bending stems and tying them in place. Because you are not removing any tissue, there is no healing process and almost no growth interruption. The plant simply continues growing—but horizontally rather than vertically.

LST is often used in combination with topping: you top the plant first to create multiple main colas, then use LST to spread those colas out horizontally so every one of them is equidistant from the light source. The result is a flat, disc-shaped canopy where no single branch shades another.

What You Need for LST

• Soft plant ties, twist ties, or strips of nylon pantyhose (avoid wire—it cuts into stems)
• Stakes or hooks along the pot rim to anchor the ties
• Small binder clips or tent stakes work as anchors in fabric pots

LST Technique: Step-by-Step

1. Start early in vegetative growth. LST is most effective when branches are still young and flexible—typically at 3 to 5 nodes of growth. Older, woody branches can crack when bent.
2. Identify the main stem or dominant branch. Gently bend it away from center and down toward the rim of the pot. The goal is to make the main branch horizontal—parallel to the soil surface.
3. Secure without overtightening. Tie the branch in place using a soft tie looped around the stem and anchored to the pot rim or a stake. The tie should hold the branch in position without cutting into the tissue. Check ties every 2 to 3 days and loosen them as the stem thickens.
4. Work the full canopy. As new branches develop (particularly after a top), bend each new branch outward and away from center. The objective is a radial pattern where all branches spread outward from the center of the pot like the spokes of a wheel, all at roughly the same height.
5. Adjust as you go. LST is an ongoing process, not a one-time event. Each time a branch grows upward (the plant is always trying to resume vertical growth), bend it back down and re-secure. This process continues throughout vegetative growth and into the first 2 to 3 weeks of flower.

LST in the First Weeks of Flower

Unlike topping and FIMing, LST can safely continue into the early flowering period. The first 2 to 3 weeks of flower—often called the “stretch” phase because many strains elongate rapidly—is an ideal time to continue managing canopy height with tie-downs. You are not creating wounds, so there is no recovery penalty. Stop LST once the plant has stopped stretching and flower development is established, typically by week 3 to 4 of flower.

Supercropping: High-Stress for Experienced Growers

Supercropping is a high-stress training (HST) technique that involves deliberately and carefully crushing the inner tissue of a branch without breaking the outer skin—then bending the branch to a near-horizontal position. The plant responds by forming a dense “knuckle” of scar tissue at the bend point. This knuckle becomes thicker than the original stem and is believed to increase nutrient and water transport to the area above the bend, producing larger flower development.

This technique is not recommended for beginners or for clones in their first vegetative weeks. The stress level is high and the margin for error is narrow—squeeze too gently and the branch springs back; squeeze too hard and you sever the branch completely. Reserve supercropping for mid-to-late vegetative growth on established, healthy plants where you have an established baseline with the genetic.

Basic Supercropping Technique

1. Select a branch at the point where you want it to bend—typically mid-branch, after a node.
2. Pinch the branch firmly between thumb and forefinger at the target point. Slowly apply rolling pressure—you are trying to crush the inner pith without breaking the epidermis (outer skin).
3. When you feel the tissue go soft and lose structural integrity, gently bend the branch to your desired angle (usually 90 degrees or close to horizontal).
4. Support the bend temporarily with a tie if the branch will not hold position on its own. Within 3 to 5 days, the knuckle will form and hold the bend permanently.

Topping + LST Combined: The Most Productive Approach

The most consistently high-yielding training approach for clone grows combines both topping and LST. The sequence looks like this:

1. Top the clone at node 4 to 5. Allow 5 to 7 days of recovery.
2. Begin LST as the two new main branches develop, bending each outward and away from center.
3. Optional second top at node 3 to 4 on each main branch (this creates 4 total main colas). Allow another 5 to 7 days of recovery.
4. Continue LST on all four branches, spreading them evenly across the canopy footprint.
5. As the plant fills out, continue tie-down adjustments every few days to maintain an even canopy height across all branches.
6. Stop topping and any cutting at least 2 weeks before the flip to 12/12. Continue LST into early flower.

This approach maximizes the number of cola sites, keeps them all at equal distance from the light, and ensures the plant enters flower with a fully established multi-branch structure. The result is dramatically better light distribution and yield per watt. For guidance on optimal light schedules for cannabis to pair with your training strategy, including when to flip and how to manage the stretch, see our detailed schedule guide.

Recovery Time and Growth After Training

Understanding recovery time helps you plan your training schedule and veg length accurately.

Always build recovery time into your veg schedule. If you need the plant to enter flower in 4 weeks, do your last hard training (topping, supercropping) by week 2 so there are 2 full weeks between the last cut and the flip. The guide to transitioning cannabis clones from veg to flower covers flip timing, pre-flower pruning, and how to read the plant’s signals that it is ready to switch.

Training Mistakes To Avoid

Topping Too Early

The most common mistake, especially with clones, is topping before the plant has fully recovered from transplant. A clone that just moved into a new medium 5 days ago is spending most of its energy establishing root-to-medium contact. Adding a top at this point means the plant is simultaneously trying to heal the cut, establish roots, and develop two new dominant shoots. The result is a prolonged stall. Wait until you see 5 to 7 days of clearly active new growth after transplant before you consider topping.

Using Dirty or Dull Cutting Tools

A dull scissor tears tissue rather than cutting it cleanly. A dirty scissor can introduce pathogens directly into the vascular tissue. Clean cuts with sterile tools heal faster and are less susceptible to rot. This applies to every cut—topping, FIMing, pruning lower growth, taking clones from clones. Wipe tools with 70% isopropyl alcohol between plants.

Topping Too Close to Flower

Topping inside the last two weeks before the flower flip leaves open wounds going into the most demanding phase of the plant’s life. The plant will spend energy on healing at exactly the moment you need all of that energy going into flower production. Stop cutting at least 14 days before your planned flip date. Use this window for defoliation and LST adjustments only.

Overtightening LST Ties

Soft plant ties can cut into stems as the plant grows—a branch that is properly tied one week can have the tie cutting off vascular flow the next. Check ties every 2 to 3 days and loosen them as needed. A constricted stem below a bud site will limit yield at that site directly. Use soft, non-cutting material and never use bare wire against the plant’s tissue.

Training a Stressed or Sick Plant

Training amplifies whatever state the plant is already in. A healthy, vigorously growing plant absorbs a top and bounces back in 5 days. A plant with a pH problem, root rot, or nutrient deficiency may take 2 to 3 weeks to recover from the same cut—or may not recover well at all. Resolve any underlying issues before training. Our cannabis clone troubleshooting guide can help you identify and fix common problems before you touch the scissors.

Skipping the Feeding Guide After Training

A topped plant with two new dominant shoots actively developing needs slightly more nitrogen than an untrained plant at the same veg stage. This is not always intuitive, but you are essentially running twice as much vegetative growth from the same root zone. Scale up feeding carefully over the week following a top—not dramatically, but incrementally. The cannabis clone feeding guide has nitrogen-forward vegetative feeding schedules that account for this increased demand.

When To Stop Training Before Flower

Timing the end of training correctly is just as important as the training itself. The goal is to enter the flowering stage with:

• All cuts healed—no open wound sites
• A clear, established multi-cola structure
• A flat, even canopy with no dominant branch towering over others
• LST ties adjusted so the canopy is locked in its final position

The general rule: stop all topping, FIMing, and supercropping at least 14 days before your planned flip to 12/12. If you are still adjusting LST ties in this window, that is fine—you are not creating new wounds. Do a final defoliation of large fan leaves that block lower bud sites 5 to 7 days before the flip, then let the plant settle into its final canopy shape before you change the light schedule.

Once you flip to 12/12, the plant’s hormonal signals shift dramatically toward flower production. Cutting at this point disrupts that process and can delay flower set or result in irregular development. The cannabis cloning techniques guide also covers how experienced growers take new clones from mother plants before the flip—a useful practice for preserving a genetic you want to run again.

Training and Genetics: Why Clone Source Matters

Training multiplies whatever potential is locked in the genetics. A mediocre genetic trained well is still a mediocre genetic. A proven, high-yielding clone trained well is a completely different grow.

When you buy a rooted clone from IWantClones.com, you are getting a proven genetic from a verified mother—not a seed-start with unknown phenotype expression. You already know the structure, the canopy behavior, the flower characteristics, and the yield potential. That predictability is exactly what makes training worth doing. You can build a training strategy around known branch architecture and growth speed instead of adapting on the fly to an unknown phenotype.

For strain selection with training in mind, look at indicas and indica-dominant hybrids for naturally wide lateral branching that responds well to LST and multiple tops. Pure sativas and sativa-heavy hybrids grow tall and fast—they respond to topping but may require more aggressive LST or SCROG nets to manage their vertical stretch. Our clone growth stages guide breaks down how different growth patterns affect training timing and approach.

Frequently Asked Questions

When should I top cannabis clones?

Top cannabis clones at node 4 to 5 once the plant has recovered from transplant and is actively growing — typically 2–3 weeks into vegetative growth after transplant. The plant should be pushing new nodes visibly before you make any cuts. Topping too early extends recovery time and may stunt overall development.

What is the difference between topping and FIMing?

Topping removes the entire apical growing tip above a node, reliably producing two new main colas. FIMing removes approximately 75% to 80% of the newest growth tip, leaving a small amount of tissue that can develop into three or four new growing points. Topping is more precise and predictable; FIMing can produce more colas but with less consistent results.

Can I top and do LST at the same time?

Yes—combining topping with LST is the most productive training approach for most clone growers. Top first and allow 5–7 days for recovery. Then begin tying the two new main branches down and outward as they develop. Continue LST throughout vegetative growth and into the first 2 to 3 weeks of flower to maintain an even, flat canopy.

How long does it take a cannabis clone to recover after topping?

Most healthy, established clones recover from a standard top in 4 to 7 days. You will see a 2–4 day pause in upward growth followed by visible elongation of the two lateral branches below the cut. By day 7 to 10, the plant is typically growing at its pre-top rate from the two new main branches. Stressed or recently transplanted plants take longer.

When should I stop training before switching to flower?

Stop all high-stress training—topping, FIMing, supercropping — at least 14 days before you flip to 12/12. This gives the plant time to heal any cut sites and stabilize its structure before flowering hormones kick in. Low-stress training (LST tie-downs) can continue safely into the first 2 to 3 weeks of flower.

Does topping hurt yield or help it?

Topping significantly increases total yield in most indoor grow setups by creating multiple main colas instead of one and distributing light evenly across a flat canopy. The short-term recovery pause (4 to 7 days) is far outweighed by the yield gains across the full flower cycle — growers commonly report 20% to 40% more usable dry weight from trained versus untrained plants under the same light.