Quick answer: LST clips are small reusable clips that hold a cannabis branch at a fixed angle so the plant sets that shape as it grows. Use them in the vegetative stage (and the first week or two of flower at the latest), bend in small steps toward a smooth curve instead of a sharp corner, and leave each clip on for about two weeks until the branch "sets," then move it. Done right, LST clips like the BudClips turn one tall cola into a flat, even canopy with many productive tops.
This guide covers what LST clips are, exactly when to use them, how to install and bend without snapping a branch, the interlocking mainline split that two-pin clips make possible, how long to leave them on, how many you need per plant, and the honest answer to whether they really increase yield.
Most plant training advice online stops at "bend your branches and tie them down." That works, but ties slip, string cuts into stems, and a knot is a pain to move once the plant grows past it. LST clips exist to make low-stress training repeatable: you clip a branch at the angle you want, the plant grows into that angle, and you reuse the clip on the next plant. This is the operator's guide to using them well - the timing, the bend mechanics, and the few mistakes that turn a training session into a broken branch.
LST clips are one tool inside a bigger system. If you want the strategy behind the tool - which branches to bend and in what order - read the low-stress training guide and the full cannabis training method. This page is about the clips themselves and how to use them without hurting the plant. And if you are working out how to grow weed indoors for the first time, LST clips are one of the easiest ways to lift your yield in a small tent.
What Are LST Clips?
LST clips (low-stress training clips) are small, reusable plastic clips that hold a branch or stem at a set angle. "Low-stress" means you are bending the plant, not cutting it: the branch stays attached and keeps growing, just in the direction you point it. A clip does one job - it holds the bend in place long enough for the branch to stiffen and keep that shape on its own.
The clips do not make a plant grow better by themselves. What they do is let you control shape, and shape controls three things that matter: how much light reaches the lower branches, how much air moves through the canopy, and how many bud sites end up in strong light instead of shaded underneath. BudClips are our version of the tool - a yellow ABS clip with two pins and a 110 degree rounded bend, built to interlock so you can train both sides of a split off the same main stalk.
The difference is structural. On the left, a freshly topped plant sends its tops straight up and shades everything below. On the right, the same kind of plant with its tops clipped open is already building a wide, flat frame. For the why behind that - how canopy shape drives light interception and yield - see how canopy shape drives yield.
When to Use LST Clips
Timing is the whole game with LST clips. They work on flexible growth and fail on stiff, woody growth. The window is the vegetative stage, with a short grace period into the first week or two of flower if the stems are still pliable.
| Stage | Use LST clips? |
|---|---|
| Seedling (in a starter cup) | No - too fragile. We do not recommend clipping plants still in a starter cup like the BudCups. |
| Vegetative | Yes - ideal. Stems bend into a smooth curve and recover fast. |
| Early flower stretch (first 1-2 weeks) | Maybe - only if the stems are still pliable. |
| Late flower | No - the plant is building bud weight, not restructuring. Support it instead. |
The rule of thumb: if the branch bends into a smooth curve, you are good. If it wants to crease or crack, you are too late or pushing too hard. Young branches near the top of the plant are almost always the right candidates; thick, hardened wood near the base is not.
Timing also depends on what you grow. For a high-yield grow, photoperiod plants get two toppings plus continuous low-stress training, while autoflowers get low-stress training only - no topping, because an autoflower runs on a clock and cannot afford the recovery time a cut demands. Clips suit both, because they hold bends without wounding the plant. If you are pairing clips with cuts, the topping guide covers where and when to cut.
How to Install LST Clips Step by Step
Installing an LST clip takes about ten seconds once you know the motion. The skill is not the clip - it is the bend. Here is the sequence.
▶ Watch the full BudClips tutorial on YouTube
Step 1: Pick the spot
Place the clip on an internode (the smooth length between two nodes) or close to a node, as long as the branch is flexible enough there to bend cleanly. The thing you are avoiding is a sharp crease at a single stress point. If the branch bends into a smooth arc, the spot is fine; if it kinks, move up the branch to younger, softer growth.
Step 2: Pre-bend the branch and insert the clip
Clip one pin onto the branch, then guide the branch gently with your fingers so it starts to give. You are not forcing the final bend here - you are testing whether the branch will reach the second pin without complaint. Think of it as telling the plant "we are going this way," not shoving it there.
Step 3: Set the angle
Install the clip's second pin and let it hold the angle. If you feel like you are fighting the branch, you are bending too far - back off and do it in two stages over a couple of days. The clip should hold a relaxed curve, not a branch under visible tension.
How to bend a branch like a pro
Bending is a skill, and the goal is to redirect growth, not punish the plant. Do it the right way and a branch that looks rigid will lay over without a mark.
- Support the branch with one hand and bend with the other.
- Use small adjustments, not one big crank.
- Aim for a curve, not a corner.
- Never bend at the thickest part near the base, and never bend a plant that is dry or stressed.
If a branch feels stiff, stop. Stiff is the plant telling you it is late. You have one more move before you give up on that branch, and it is the squeeze.
The branch squeeze technique
When a branch is too hard to bend cleanly but not yet fully woody, you can soften the inner tissue so it curves instead of snapping. Put two fingers and your thumb around the branch where you want the bend, gently squeeze and roll the stem for a few seconds (you are softening it, not crushing it), then bend slowly into position and install the clip. It is not magic, but squeezing beats breaking.
How to Build the Mainline Split With BudClips
This is where a two-pin clip earns its keep. A "mainline split" is not "tie two arms down" - it is a specific setup on the main stalk that forces both top branches to thicken sideways into a strong, symmetric manifold that can carry heavy buds later. Single-pin clips and bare ties cannot do it cleanly; interlocking two-pin clips can.
The mechanic is simple once you see it. Attach the first clip's pin to the main stalk, just below the top node you are training, then guide the top branch under the second pin so the stalk acts as the anchor and the branch sets in place as it thickens. To train the other side without the clips bumping into each other, you interlock a second clip into the first. That interlock is what lets you pull both branches off the same stalk evenly, so one side does not run away from the other during fast growth.
After about a week, those small top branches should be wider and stronger, with a thicker "knuckle" where any squeeze point formed. From there you repeat the same idea on the next node down. If the main stalk is already too thick to clip cleanly - thicker than roughly a finger, about 2 cm (0.8 in) - place clips higher on the branches instead and skip the interlock - you still get a strong, trained structure. For the full method, including how this builds 8, 16, or 32 colas, read how to mainline cannabis and the related manifold guide.
How Long to Leave LST Clips On
This is the single most common place growers go wrong. LST clips are not meant to live on the plant forever - they stay on until the branch sets, then they come off or move.
"Set" means that when you remove the clip, the branch mostly holds its new position and does not spring aggressively back. As a general rule, leave a clip on for about two weeks, three at the most, then remove or reposition it. During fast vegetative growth, check daily: if it has been a week or more, the stem is visibly thickening, and the clip is starting to look tight against the branch, take it off. A clip left on a swelling stem stops holding shape and starts choking it.
Do LST Clips Actually Increase Yield?
Honest answer: the clip does not increase yield. Structure does, and the clip is how you build the structure. A piece of plastic holding a branch is not adding grams - what adds grams is turning one shaded, single-cola plant into a flat canopy where many tops sit in strong, even light. The clip is just the cheapest, most repeatable way to get there.
The research backs the mechanism, not the marketing. Manipulating plant architecture so light is distributed across the canopy measurably changes how a cannabis plant allocates growth and standardizes the flowers it produces.1 The amount of light a canopy intercepts is itself a primary driver of photosynthesis and final yield,23 which is the entire reason for spreading a plant flat to catch more of it. A meta-analysis of cannabis yield factors puts light and canopy management among the levers that matter most.4 None of that happens because the clip is special; it happens because an even canopy intercepts more usable light than a Christmas-tree-shaped one.
So if someone promises that a clip alone grows bigger buds, be skeptical. The clip is leverage on your own labor: it makes good canopy structure fast and repeatable, and good structure is what the evidence links to higher, more uniform yields.
How Many LST Clips Do You Need?
Enough to build a balanced canopy, not enough to fill a drawer. The number scales with how many plants you run and how aggressively you train, but these are the ranges we see hold up in real grows.
As a quick reference: around 20 clips for 1 to 2 plants, 40 for 3 to 4 plants, and 100 for 8 to 10 plants. Because plant training clips like the BudClips are reusable indefinitely, you buy them once and they roll forward to every grow after. Buy for the canopy you are actually building, not the one in the seed-bank photos.
Mistakes to Avoid With LST Clips
Almost every clip problem is one of four mistakes. None are subtle once you know them.
- Leaving clips on too long. The number-one error. A clip on a thickening stem goes from holding shape to constricting it. Fix: check daily during fast growth and pull clips once the branch sets.
- Training old, woody branches. Old branches do not bend, they crack. Fix: train earlier, or use the branch squeeze before you bend a borderline-stiff stem.
- Training a stressed plant. Drooping, heat-stressed, or nutrient-burned plants do not have spare energy for training. Fix: stabilize first, train second.
- Doing too much in one day. Heavy defoliation plus a big bend plus a transplant plus a feed change is a stack of stress that stalls the plant. Fix: change one major variable at a time.
If you do crack a branch, do not panic. A light crack that is still attached usually heals: support the branch so it is not hanging on the wound, press the split closed and wrap it with a repair tape like the BudTape, then reduce the bend and leave it alone to recover. For the full repair, follow the broken branch guide. If a branch snaps off entirely, cut it back cleanly to the nearest node and let the plant redirect growth - it will.
Cleaning and Reusing LST Clips
Good LST clips are a buy-once tool. BudClips are reusable for the life of the grower, not the grow. After a harvest, wash them in warm soapy water, rinse thoroughly, and dry fully before storage. If you are moving clips between plants mid-grow - especially if one plant had pests or disease - sanitize with a mild disinfectant or with ethanol followed by soapy water so you are not couriering problems from one plant to the next.
Where LST Clips Fit in a High-Yield Grow
Clips shape the branch, but a branch only responds well if the rest of the plant is healthy. LST clips work on any plant in any container, and they work best when the roots and the pot are set up to support training instead of fighting it.
Roots come first. Strong early roots mean faster veg, better recovery after a bend, and thicker branches that hold a set - which is why we start seedlings in starter cups like the BudCups before any training begins. Once the plant is in its final home, a fabric pot like the BudPots keeps the root zone oxygenated and well drained, so the plant shrugs off the stress of bending instead of sulking. And for guiding whole branches outward and holding canopy spacing, branch ties like the BudHuggers hook straight into the pot's grommets and split the work with the clips: clips set the bend, ties guide direction.
Frequently Asked Questions
What are LST clips?
LST clips are small reusable clips that hold a cannabis branch at a set angle during low-stress training. Instead of cutting the plant, you bend a branch and the clip keeps it there until the branch stiffens and holds the new shape on its own. They are used to open up the canopy so light and air reach more bud sites.
When should you use LST clips?
Use LST clips during the vegetative stage, when stems are flexible and bend into a smooth curve. You can still use them in the first one to two weeks of flower stretch if branches remain pliable. Avoid them in late flower, when the plant should be supported rather than reshaped, and on stiff, woody growth that wants to crack.
How do you use LST clips without breaking the branch?
Support the branch with one hand and bend with the other, in small steps, aiming for a curve instead of a sharp corner. Clip one pin, test the bend, then set the second pin without forcing it. If a stem feels stiff, use the branch squeeze technique first or bend it in stages over a couple of days.
How long do you leave LST clips on?
Leave a clip on until the branch sets, usually about two weeks and three at the most, then remove or reposition it. The branch is set when it holds its position after the clip comes off. Check daily during fast growth, because a clip left on a thickening stem stops holding shape and starts constricting it.
How many LST clips do I need per plant?
It depends on plant size and how hard you train, but a workable range is about 20 clips for 1 to 2 plants, 40 for 3 to 4 plants, and 100 for 8 to 10 plants. The goal is a balanced canopy, not a clip on every branch. Because quality clips are reusable, you only buy them once.
Do LST clips actually increase yield?
Not on their own. The clip does not add grams; the canopy structure it builds is what matters. Spreading a plant flat so many tops sit in even light is what research links to higher, more uniform yields. The clip is simply the fastest, most repeatable way to build that structure, so treat it as leverage on your training, not a magic part.
Can I use LST clips during flowering?
Only early, and sparingly. If you must train in flower, limit it to the first two weeks of stretch while stems are still pliable. After that the plant is committing energy to bud weight, and bending stresses it at the worst time. Late flower is for support, not reshaping, so switch to ties and props instead of new bends.
Are LST clips better than wire or plant ties?
For setting and adjusting bends, yes. Wire and ties work, but they are slower, messier, and can cut into a stem if they are too tight. Clips are faster to install and remove, easier to reposition, and more repeatable for consistent structure. Ties still have a role for guiding whole branches outward, which is why many growers use both together.
Is LST better than topping?
They do different jobs and work best together. Topping cuts the growing tip to create more main colas; low-stress training with clips bends what is already there to flatten the canopy. Topping is a wound the plant must recover from, so it is for photoperiods only. LST is gentle enough for any plant, including autoflowers, which should be trained but never topped.
Can I use LST clips on autoflowers?
Yes, and they are the right tool for autoflowers. Because LST clips bend rather than cut, they shape the plant without the recovery time a topping cut demands, which an autoflower on a fixed clock cannot spare. Start early while stems are soft, keep the bends gentle, and you can flatten an autoflower canopy without slowing it down.
Are LST clips reusable?
Quality clips are reusable indefinitely. BudClips are molded from durable ABS plastic, so after a grow you wash them in warm soapy water, dry them, and store them for the next round. If you move clips between plants, sanitize them with a mild disinfectant or ethanol first so you do not carry pests or disease from one plant to another.
Can I use LST clips on plants other than cannabis?
Yes. Any plant with flexible stems benefits from structural training, including tomatoes, peppers, and many fruiting vegetables. The same rules apply: train young, pliable growth, bend toward a curve, and remove the clip once the branch sets. The clips do not care what species they are on - they care whether the branch is flexible enough to bend cleanly.
What do I do if I crack a branch while training?
If the branch is still attached, support it so it is not hanging on the wound, press the split closed, and wrap it with a repair tape like BudTape, then reduce the bend and leave it to heal. Most light cracks recover in days. If the branch snaps off entirely, cut it back cleanly to the nearest node and let the plant redirect growth.
Next Steps in Your Grow
LST clips are Lesson 4's favorite tool, but they are one step in a longer method. A full, high-yield grow runs picking the right seed type to germination to planting to transplanting to training to flowering to harvest.
If you want the strategy that decides which branches to clip and when, start with the low-stress training guide, then layer in topping once your plant can take it. When you are ready to buy the tool, a pack of BudClips is the cheapest leverage you can put on a grow: bend the plant flat, hold it there, reuse them forever, and let an even canopy do the rest.
References
- Danziger, N., & Bernstein, N. (2021). Plant architecture manipulation increases cannabinoid standardization in drug-type medical cannabis. Industrial Crops and Products, 167, 113528. https://www.sciencedirect.com/science/article/pii/S0926669021002958
- Chandra, S., Lata, H., Khan, I. A., & ElSohly, M. A. (2008). Photosynthetic response of Cannabis sativa L. to variations in photosynthetic photon flux densities, temperature and CO2 conditions. Physiology and Molecular Biology of Plants, 14(4), 299-306. https://link.springer.com/article/10.1007/s12298-008-0027-x
- Potter, D. J., & Duncombe, P. (2012). The effect of electrical lighting power and irradiance on indoor-grown cannabis potency and yield. Journal of Forensic Sciences, 57(3), 618-622. https://onlinelibrary.wiley.com/doi/10.1111/j.1556-4029.2011.02024.x
- Backer, R., Schwinghamer, T., Rosenbaum, P., et al. (2019). Closing the yield gap for cannabis: A meta-analysis of factors determining cannabis yield. Frontiers in Plant Science, 10, 495. https://www.frontiersin.org/articles/10.3389/fpls.2019.00495/full
About the Author
Henrique Dias is the CEO and co-founder of BudTrainer. He is a mechanical engineer who also holds a graduate certificate in Commercial Cannabis Production from Niagara College in Ontario, Canada - the first college-level cannabis cultivation program in North America. Before founding BudTrainer, Henrique worked with Health Canada licensed cannabis producers, where he gained hands-on experience in cultivation, processing, and post-harvest management of cannabis at commercial scale. He started BudTrainer to bring that same level of craft to home growers through better-designed gardening tools and clear, science-backed education.
DISCLAIMER: Everything taught and sold by BudTrainer® is to be used strictly for legal purposes. We do not endorse the production of illegal substances and it is your duty to ensure that you are complying with the law. The words "hemp," "cannabis," "weed," and "marijuana" are used interchangeably to refer to the same plant (legal hemp with less than 0.3% THC) for the purposes of this lesson.
