The marijuana vegetative stage is the most crucial life stage that your cannabis plant will go through. It comes right after you have planted your germinated seeds and lasts all the way up to the flowering stage. It is not easy to say how long the vegetative stage will last, mainly because it depends on the particular strain you have chosen.

This phase is especially important for growers, as proper care during the vegetative stage will mean better quality bud later on. Providing them with ample light, proper nutrients and of course, training them to improve their performance are only some of the things that you should do when your plants are in the vegetative stage.

What is The Marijuana Vegetative Stage

About two weeks from germination, your marijuana plant will start growing out from the seedling phase and officially enter the vegetative stage of its development. Indoors, this stage can last indefinitely (if you are not growing an autoflowering plant), as long as the light schedule is between 16-24 hours per day. Some growers tend to keep their plants in vegging mode for longer, while others force flowering earlier. Typically, the vegetative stage lasts three to four weeks for most indoor strains, although this amount of time can be influenced by lighting, environment, disease or outdoor conditions.

During this time, your plant will enter a growing frenzy, as it will start developing a robust root system and a core that will support its flowers later on. Also, foliage will begin to form, meaning that the plant will be flexible enough for manipulation. Although plant training is not essential, it can significantly improve your yields. and we’ll talk about it in depth in the following sections.

The Seedling Phase

The seedling phase usually ends after a couple of weeks. The first one or two leaves your plant will produce are called cotyledons. After that, you will notice that the number of leaves (lamina) that the plant produces will start increasing progressively as the plant develops, usually capping at around ten.

Marijuana Seedling Phase

During that time, you’ll also notice that branches will also begin to appear. While it is in the seedling stage, you’ll want is provide your plant with nitrogen-rich fertilizers (preferably organic mixes). A small dosage of nutrients will go a long way, so be careful not to damage the tiny seedlings. At this point, light intensity and distribution are the key factors behind plant development.

Light During the Vegetative Stage

Whether you are an indoor or outdoor grower, lighting will always be the most critical factor in the overall health of your plant. That does not only apply to the vegetative stage, but it is during this time that you should provide strong, bright light to your plants to prevent them from overstretching.

The more intense light you can provide, the better! Of course, heat is always something you need to take into account, so check our simple five-step tutorial on growing. If you are growing outdoors, then you are lucky enough to have the galaxy’s most efficient grow light (the sun) at your disposal, but that doesn’t mean your responsibilities end there.

Indoor Lighting

As we mentioned above, the recommended indoor light schedule for the marijuana vegetative stage is 18 or 24 hours of continuous light. However, intensity is also important, and it is something you should take into account. Intensity is measured in Lux (lx). To get a sense of perspective, on a cloudy day, the Lux levels are about 10,000lx, while on a bright summer day, we can measure over 90,000lx.

LUX chart

There are no perfect solutions regarding grow lighting, although an HPS or LED fixture will serve you right in most cases. Think 250W of actual power for every four plants in your grow room. You might be tempted to get a stronger grow light, but you won’t achieve anything, as most of this light will go to waste.

If you think you need supplemental lighting for your grow, you can do it with cheap ‘Soft White’ (2700k) or ‘Cool White’ (6500k) colored CFLs and place them strategically in under-lit areas. The ideal lux levels for marijuana plants are:

  • 35,000 – 70,000 lux during the Vegetative stage
  • 55,000 – 85,000 lux during the Flowering stage.

You can measure these levels quickly with a lux meter (they are pretty cheap). However, as long as you are even a little bit careful, you shouldn’t run into any significant problems. Marijuana plants are very forgiving to mistakes!

Growing Outdoors

Natural lighting is infinitely better for your plants, although outdoor growers have to take into account many environmental factors. The best time to plant your germinated seeds outdoor is during spring (around April-May), depending on your location. As long as the days last more than 12 hours, your plants should be ok. If the plants are exposed to prolonged darkness right away, they might start budding prematurely.

After that it’s only a matter of proper watering, fertilizing and basic care. Pay close attention to the leaves of your plant to make sure no bugs or mites have appeared. In warmer climates and places with a lot of sun marijuana plants can grow as tall as 3 meters within one summer! Flowering will occur naturally as days become shorter and this usually happens faster in areas that are far away from the equator. The closer you are to the equator, the longer it will take for marijuana to flower.

Training and Pruning During the Marijuana Vegetative Stage

It is not mandatory to train or prune your plants, so feel free to ignore this advice. However, doing so will help you achieve far higher yields than the ones you would if you let the plant grow in its natural state. The reason for this is that plant training increases the canopy, ensuring that the plant will get a more even light exposure.

Bud sites develop in the parts of the plant that are more exposed to light. If left untrained, a plant will produce big healthy buds on top and puffy, “popcorn” buds in the areas that didn’t get enough light. Growers have seen their yields improved by more than 50% with proper training, so it’s worth a try even if you’ve never done it before.

Training methods involve two major subcategories: Low-Stress Techniques, that involve manipulating the plant’s shape without hurting it and Pruning Techniques, which is slightly more advanced and requires that you “injure” your plant strategically to increase its health.

Low-Stress Training Methods

This subset of training methods is tested and straightforward ways of dramatically improving the yield of your plant and managing its size. This is especially important if you are growing indoors and equal light distribution is more difficult to achieve. LST methods involve bending the stems, tying them with soft wire or “supercropping.”

low stress training

This is pretty much how a trained marijuana plant looks like in the vegetative stage.

The general idea is to bend and manipulate the plant’s growth patterns to your advantage, with the ultimate goal of producing more buds in a flat canopy. To do this, just tie or bend branches that grow taller from others, and secure them in place so they will expand horizontally rather than vertically.

Supercropping is the technique that involves the gentle “crushing” of weaker branches. This will injure the plant slightly and will force it to regenerate by strengthening the affected area. This is the core philosophy of pruning methodologies, that we’ll see below.

Pruning Methods

These methods are more radical but can reward you with a much more vigorous plant. Contrary to the mostly harmless LST methods, pruning requires at least some level of knowledge before you start. It is a good idea to have both small and bigger sets of sharp scissors. You don’t want to end up tearing your plant apart: The incisions should be quick and clean.

The best timing for pruning is in the early vegetative stage when the plant’s foliage is not so dense. You can continue to prune your plant all the way to flowering, but not after that. Hurting your plant during flower might revert it to the vegetative stage, as it will try to recover from this harmful event and cut its losses!

There are two major types of marijuana pruning: Topping and FIMing.

fimming topping

So easy to miss, right?

Topping

Topping is simple and involves the complete removal of the top of the plant’s main stem. In theory, this will disrupt the plant’s natural tendency to grow one main kola and will split the development into two main branches. The extra stalks will grow right above the node where you made the incision. If you do this early enough (during the early vegetative stage), the plant will continue growing that way, increasing the canopy.

FIMing

FIM stands for “Fuck, I Missed) and it’s a technique closely related to topping. In FIMing, you just pinch off the very top of the plant (instead of cutting between the internode). The goal is pretty much the same as topping, but the downside of FIMing is that it is less likely to accomplish it. However, it is much less stressful for the plant.

Timing is Key!

Both techniques can yield results, however, you need to implement them at the right time. If you do it too early, you might end up hurting the plant. The optimal time is to wait until the plant has grown at least five nodes (for FIMing) and six nodes (for topping).

Pruning and training work for the plant the same way exercise works for the human body. You must let the plant recover after training, to avoid triggering a hormonal reaction that will impede growth. Although these techniques might seem complicated and/or dangerous, they are in fact valuable both for you (you will greatly improve your skills) and the plant (it will grow healthier).

Things to Note During the Marijuana Vegetative Stage

Before I wrap this article up, I’d like to share some quick tips about the vegetative stage with you.

  • Watering: Remember to only water when the topsoil feels dry to the touch.
  • Lighting: If growing indoors, make sure that your plants get more than 16 hours of continuous bright light, while also making sure that the canopy is at a safe distance from the lamps. Outdoors, nature has got you covered: just plant in mid-spring (or later, if you live near the equator).
  • Temperature: Remember that if it’s too cold for you, it’s also cold for your plants. Optimal temperatures are about 18-30ºC.
  • Nutrients: Use nutrients sensibly and start with half the recommended dosage. Use organic if possible, to avoid contamination by chemicals.
  • Bugs: Watch out for any nasty critters on your plants. Some insects (and pets) like to chew on marijuana plants.
  • Disease, Mold & Rot: Mold and rot are usually accompanied by a foul smell and are caused by bad air circulation. Make sure that your grow room has adequate ventilation and inspect the leaves daily for signs of mold or white powder (powdery white mildew).

The marijuana vegetative stage is the prologue to the flowering phase, which comes with its own set of challenges for the grower. The healthier your plant is during vegging, the bigger the chances of a high yield during flowering.