Cleaning up your plants starts with understanding what your plants need and ends with understanding why you’re doing the things you’re doing, whether you’re removing growth nodes, entire branches, or simply snipping a few larger leaves. Understanding the difference between defoliating and cleaning up your plants will help to guide your efforts based on the endgame in sight. Removing unnecessary or unhealthy growth can remove obstruction, ensure optimal nutrient usage, help with growth and canopy training, assist with pathogen prevention and the cleanliness of the grow and ensure an even environment without stagnant pockets of air that could present issues. However, there are plenty of reasons to keep these leaves and growth nodes as well, including their storage of nutrients for when plants need them most.
Defoliation vs. Cleaning Up Plants
Often, the term “defoliation’ is used incorrectly to refer to the removal of any unwanted part of the plant. It is important to know the difference between common terms such as defoliation, cleaning up, and lollipopping plants.
Defoliation: The removal of leaves that are impairing the plant’s growth more than helping to stimulate it.
Cleaning Up Bottoms: Removing thin, unwanted branches, and growth nodes on the inner part of the plant that aren’t going to develop or prosper.
Lollipopping: This is an aggressive type of removal where the majority of lateral branches, nodes, and fan leaves (typically at or below the intended canopy) are removed leaving branches naked, resulting in large buds developing on top (resembling lollipops).
Cleaning up to me is more about approaching the plant from the bottom up, removing branches, leaves, and nodes that likely won’t reach the canopy.
Defoliation for me is typically from the top down or middle out depending on the plant, with the goal of removing leaves that have served their purpose. I only defoliate when I think the plant needs it; I don’t do it just to do it. It is important to listen to your plant and respond to what it needs. There is no timeline for defoliation; it is a perpetual process of removing as needed.
5 Reasons to Clean Up & Defoliate Your Garden
1. Remove unneeded growth. Growth that will not catch up to the canopy or has little hope of fully maturing by harvest is growth that steals nutrients from the rest of the plant. By removing these growths (nodes and branches), you are allowing the plant to allocate nutrients more efficiently to the parts of the plant that will fully develop as desired.
2. Growth coaching. Sometimes plants don’t grow evenly or cover the space you need (especially when training for a specific space as with trellis). In these cases, you can train the plant to grow a certain way by defoliating and lollipopping. This can help in general with the symmetry of a plant. If one branch is not quite filling its gap, clean up that branch and lollipop it until it catches up and reaches the canopy.
3. Remove obstructing growth. This is the most common reason for defoliation, often applied too liberally. As leaves get bigger, it can be tempting to remove them to expose lower growth sites to more light. Understanding the function of that leaf will help determine if it should be removed. This must be done perpetually (and often daily), being careful not to remove leaves that the plant is still using. I tend to defoliate these large leaves only after the node attached to them has developed five autonomous growth nodes of its own.
4. Cleanliness of your plants. It is much easier to keep a clean grow when there isn’t unnecessary jungle-esque foliage everywhere. It’s also easier to spot issues before they become problems, such as intersex issues and pathogens that could ruin your grow.
5. Evenness of your environment. By removing unneeded growth, you are helping to maintain proper airflow in your grow. This helps to prevent stagnant pockets of air that can encourage pathogens and pests.
Reasons to KEEP your Leaves
While there are many logical reasons for removing leaves and growth from the plant, there are tons of reasons to keep those leaves as well. In their early stages, growth nodes are developing vigorously and need energy and nutrients that the leaf attached to them provides. Each leaf feeds a growth node. When that growth node develops four or five of its own growth nodes, it becomes autonomous, no longer needing the energy from that leaf as it now has it’s now producing its own. My rule is a minimum of five growth nodes before I remove the fan leaves at the bottom of a plant. If you do it too early, you’ll stunt the growth of that branch; if you’re confined to a specific space, you can also use defoliation to purposefully stunt the growth of these branches rather than topping the plant.
It’s primarily about understanding the function of the leaf. Leaves are the solar panels of your plant; they create tons of photosynthesis for the plant, and each leaf's individual importance is determined by a lot of variables including how many other leaves are on the plant and the size of that plant and location of those leaves. Sometimes, leaves are very important to the plant. Other times, those leaves are stealing amino acids that can impact your yield and are no longer serving a direct function to the plant. The further down the plant’s branches that you allow growth nodes, the more energy you are removing from the top of the plant, which can exponentially impact your yields. This is important to keep in mind not only for cleaning up, but also when removing larger leaves from the top of the plant; the tops of your plant may need that light more than the lower growths that you are removing the leaf to expose. Lower buds are smaller buds, and exposing more areas of the plant to light doesn’t always translate to more flower.
My goal is to remove anything mediocre under the plant. I don’t want any larf on my plants that consume the air and nutrients, stealing them from my tops. Additionally, this lower growth is consuming nutrients, producing excess salts and transpiration. I keep my plants clean underneath, removing internodes beneath the bottom of branches in veg and very early in flower.
Cleaning Up From Seed
You want to make sure you leave seedlings alone for the first 3-4 weeks while it is still getting out of the gate. Keep the plant vertical and keep it from overstretching (light deficiency). I typically won’t defoliate a seed until Week 5 and it’s a very light defoliation at that. Around Day 30 is when I really start to look at the plants to determine if nodes or leaves should be removed. I’ll clean up a seedling before I defoliate, removing bottom branch sets or at least one growth node on the lower branches.
Some plants have huge leaves that are generally obstructing growth, typical of plants with shorter internodes and large leaves. In some cases, I might even take 2-3 leaves as early as Week 4 (from seed). These are cases where the leaves are half the size of the plant. Otherwise, I try to leave them for the growth nodes until they have 4-5 nodes of their own; each leaf provides energy and feeds each node that it is connected to. Secondarily, like a camel hump, nutrients can be taken from that leaf later if needed by that branch.
At this point, I’m also cleaning up the bottoms of my plants, removing branches and nodes that don’t have the lateral growth vigor desired, lollipopping early and often. I start with the bottom first, judging whether those branches will make it out from under the apex growth and be able to grow autonomously. If not, I remove them. I don’t mind removing lower growth as the top makes up for the yields. If the branches have what it takes to make it out, at that point I start assisting them, lollipopping the bottom growth sites to allow those branches to catch up with the rest of the plant.
Cleaning Up From Clone
Because seeds take time to get to sexual maturity and clones do not, you have a bit more creative freedom. I clean up and defoliate as needed, removing unnecessary growth except for the top cluster of growth nodes of the clone. This makes it much easier for pathogen prevention (now and in later stages of growth) as there is much less plant for pests and pathogens to be attracted to. Once I see new growth on the clone, I remove any old growth (original leaves and nodes from when the clone was taken). By day 10 from clone, I want all growth on the plant to be new original growth; nothing that was from the original plant remains as these older leaves are often where pathogens reside or take hold. Not only can older growth bring problems with it from the mother plant, but older growth is also more susceptible to pathogens.
Cleaning Up and Stress
Sterile tools or frequently washed hands should be used when handling plants. The amount of stress removal causes depends largely on the fiber content of the epidermis (the skin of the plant). Fresh, new, green growth that is higher in water content often will pop right off with much less effort without stressing the plant out, meaning you won’t need scissors or blades to cut those. Others are fibrous, that would need pulling or yanking, and in these cases I will use scissors to avoid unnecessary stress.
By removing leaves and nodes, you are streamlining the hormones in these branches, and it shouldn’t be enough stress to dramatically impact the plant. Daily cleanings with small removals here and there are not going to put the plant through any sort of dramatic physiological change from day to day, nor are these cleanings likely to cause intersex issues. Just remove a few nodes here and a few nodes there, and try to take things gradually to avoid pushing plants that may be prone to sexual stability issues.
Cleaning Up Photos vs. Autos
If the plants are grown the same way, a photo and an auto seed with similar vigor, both put into the same size pots at the same time, can be cleaned up in a similar fashion. I would treat those plants the same if my endgame was just flowering both of them. The main difference between photos and autos is that a photo-period plant is typically sent into 12/12 after Week 5, while an auto flower will naturally begin to flower when it is ready. I recommend similar training and conditioning if grown in the same method. While I rarely grow photo-period seeds the same every time, I am dogmatic with auto flowers because of the clock.
When to clean up and/or defoliate?
There’s no definite answer to when to clean up your plants, and I don’t follow rigid rules. I will often be defoliating every day on a small level, and then maybe heavily once or twice through the cycle during Week 4 and Week 8 of flower. I typically follow a moderately heavy defoliation process, but it is very strain dependent. With Super Lemon Haze, the leaves are scant and have very thin blades, so I don’t defoliate that plant at all. I’ll clean up growth nodes underneath, maybe remove a few leaves underneath the plant on the lower branches, but typically I don’t have to defoliate that genetic. The internodes are medium-long and there are never leaves that are overtly covering areas of the plant. There’s some thin shading here and there, but a plant like that doesn’t really need defoliation.
It’s all about understanding how much flower is dependent on the leaf you are removing. In GSC, removing a huge leaf from a bud that isn’t going to grow that much makes sense because even if you take it off, the bud attached to that leaf isn’t going to grow much anyway. But if you have a leaf attached to internode that is important in the growth phase, wait a few days because the plant needs that energy.
I also don’t have a hard cut off for cleaning up the plant. It is important to be flexible from seed (or clone) to harvest. Don’t be overzealous and defoliate a seed as it pops, and be careful when removing leaves in the first half of flower to ensure that the plant and flower no longer need that leaf. It’s different in every system. If you are in trellis, you will defoliate more than plants that are more open and have more distance between branches. Grow style, humidity and circulation in the room are important factors; if you have lower airflow, defoliate those plants more to open the airways. The #1 thing is to listen to your plants.
There are a ton of conditions that dictate keeping or removing growth from your plant, and you shouldn’t do anything unless you know why you are doing it. If you’re cleaning a plant up, you’re working to redirect nutrients to growth that you are nurturing; If you’re defoliating, you’re removing growth that no longer serves a purpose.