What Is Topping Cannabis?
Topping cannabis means cutting off the plant's top growing tip so it grows two main stems instead of one. You make the cut during the vegetative stage, above a node, after the plant has built at least 4 to 6 nodes. The plant answers with two new leaders where there used to be one.
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It is one of the oldest low-stress training moves in cultivation, and it costs nothing but a pair of clean snips. The payoff is a shorter plant, more bud sites at the same canopy height, and better light use in a tent or room.
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Why Does Topping Work?
Cannabis sends energy to its highest shoot first. A hormone called auxin gathers in that tip and holds back the branches below it, a pattern known as apical dominance.
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Remove the tip and you remove that auxin source. The two nodes closest to the cut break free and grow upward as new main stems. Top those later and the count doubles again.
- 1 top = 2 main colas
- 2 tops = 4 main colas
- 3 rounds in veg = 6 to 8 main colas
More tops mean more colas sitting at an even height. Even height matters indoors, because light falls off fast with distance from the fixture.
When Should You Top a Cannabis Plant?
Top once the plant has 4 to 6 nodes and shows strong, healthy growth. That timing gives it enough leaf area to heal and enough veg time left to build new tops.
Stop at least 10 days before you switch to 12/12. Plants cut right before the flip spend the stretch phase repairing instead of stretching, and the flower sites come in smaller.
Not sure where to start counting? Node 1 is the first set of true serrated leaves above the round seed leaves. Count upward from there.
Timing by plant type
- Photoperiod: top at node 4 to 6. Repeat every 2 to 3 weeks while the plant stays in veg.
- Autoflower: top only at node 4 or 5, and only if growth is strong. Skip it after day 21 from sprout, since the clock never stops.
- Clones: wait until roots are set and 3 to 4 new nodes have formed.
How to Top a Cannabis Plant, Step by Step
You need sharp scissors or snips, rubbing alcohol, and clean hands. Work in the first hours of the light cycle so the plant has a full day to begin repairs.
- Find the newest growth at the very top of the plant. You want the small shoot sitting above the highest set of fan leaves.
- Count down to the node below it. The cut goes just above that node, leaving a short stub of stem.
- Pinch or snip the top shoot off. Leave the two tiny growth tips at the node below untouched.
- Wipe your blades with alcohol between plants to avoid spreading pathogens.
- Leave the plant alone for 3 to 5 days. No heavy defoliation, no transplant, no big changes.
Those two growth tips at the node are the whole point. Cut below the node and you lose them, and the plant starts over from scratch.
Topping vs FIMing vs LST
Topping is a hard cut, FIMing is a partial cut, and low-stress training bends stems without cutting anything. They stack well together, but they are not the same job.
- Topping: full removal of the top shoot. Predictable, two new colas, slower recovery.
- FIMing: pinching about 75% of the top shoot. Can give 3 to 4 tops, less predictable, faster recovery.
- LST: bending and tying stems flat. No wound, spreads the canopy wide, pairs well with topping.
What Should You Do After Topping?
Give the plant a calm week. Keep light, water, and nutrients at the same levels you were already running.
A light dose of nitrogen plus kelp or vitamin B can help the wound close, but the plant does not need a heavy feed. Overwatering a freshly topped plant is a common way to stall it.
New tops should show up within 3 to 7 days. If nothing moves after 10 days, check root zone temperature, pH, and light distance before you feed anything else.
Topping for Different Grow Styles
The number of tops you want depends on your space and your method.
- SCROG: top twice, then weave the four tops through the net during stretch.
- Manifold (mainlining): top at node 3, strip growth below it, then top each side once more for 8 even colas.
- Small tent or cabinet: one or two tops keeps height down.
- Outdoor plants: topping early builds a wide bush that handles wind better.
Tall, stretchy sativas gain the most from topping indoors. Short, bushy indicas may need only one cut, since they branch on their own.
Common Topping Mistakes
- Topping before node 4, when the plant has little material to work with.
- Cutting below the node and losing both growth tips.
- Topping in flower. It wastes energy on repair and can stress the plant into herming.
- Topping an autoflower past week 3 and stunting it.
- Topping a sick or slow plant. Fix the problem first.
- Stacking topping with a transplant or heavy defoliation on the same day.
Frequently Asked Questions
Does topping increase yield?
Topping can raise yield when the extra tops get even light and room to fill out. It can lower yield if the plant is topped late, topped too many times, or grown in a space too small for the wider canopy. The plant does the work, not the cut.
Can you top a cannabis plant in flower?
No. Once flowering starts, the plant stops building new structure and any cut goes to waste. Top during veg, then stop.
How long does a topped plant take to recover?
Most plants resume growth in 3 to 7 days. Getting the new tops to match the size of the old leader takes about 1 to 2 weeks.
How many times can you top one plant?
Two to three rounds is typical for a photoperiod plant in a tent, and that yields 4 to 8 main colas. Extra rounds add veg time and sprawl.
Should you top autoflowers?
Only if the plant is vigorous and you top by node 4 or 5, before week 3. Otherwise use LST and let it run.