What to Do with Cannabis Fan Leaves? (vs Sugar Leaves)

There are two types of leaves on the cannabis plant: sugar leaves and fan leaves. The fan leaves are a crucial part of its anatomy! They hold many functions, and give you a good idea of what's happening within the plant, as well as within the root zone!

In this article, we will cover the functions and purpose of cannabis fan leaves, what they contain, and the difference between sugar leaves and fan leaves!

What Do Cannabis Fan Leaves Do?

cannabis fan leaves

Fan leaves have many essential functions that help the cannabis plant grow!

1. Photosynthesis

They are the primary site of photosynthesis, converting light into energy and sugars for the plant to use.

Additionally, these leaves store sugars and minerals, and transport them to other parts of weed plants when needed!

2. Transpiration

Fan leaves are also large sites for transpiration, a process where the cannabis plant releases excess water through pores in the leaves, known as stomata. This process helps regulate the plant's temperature and moisture levels.

3. Protection for Flowers

Beyond their physiological functions, fan leaves are also used as protective shields for the plant, shielding the fragile and delicate parts like flowers.

4. Health Indicator

One of the most important functions of cannabis fan leaves to growers is they can provide valuable insights into the plant's health!

The fans leaves will turn yellow, discolor, or contain spotting when there is a nutrient deficiency, or toxicity within the plant.

They will also give you a good idea of what's going on with the grow environment or root zones.

cannabis leaf tips curling down

When the cannabis leaf curls downwards, it reveals issues in the grow environment—either too hot or cold, or too dry or humid. Downward pointing leaf tips may also signal problems occurring in the root zone, like root rot or tissue damage.

Fan leaves may also show other signs of stress, most commonly light stress, refelcted in many fan leaves only producing 1 or 2 blades on each leaf!

Many growers find it useful to keep a grow journal to track abnormalities seen in the fan leaves. Track your plant's journey and address issues seamlessly with the hey abby app (IOS/Android). This helps identify changes and reduce variables, allowing for repeatable success from grow to grow!

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Do Fan Leaves Contain Cannabinoids?

cannabis edible made of fan leaves

The simple answer is yes, fan leaves do contain cannabinoids. But, they are found in much lower concentration than in the actual flowers and sugar leaves of the plant.

Fan leaves are not commonly used for medicinal purposes, however some people will use them to make teas and cook with!

Should I Trim Fan Leaves?

You should remove the fan leaves occasionally, especially during the veg stage! Fan leaves act as protection for the cannabis plant, but they can inadvertently block valuable light and air flow!

It is important to know which leaves to remove. You will want to remove any large leaves that are attached to the stalk or branch, just under a growth site. Once the growth site has developed the ability to branch off, or grow independently from the stalk or branch it originated from, it no longer relies on the leaves attached under it. And now those fan leaves can be safely removed!

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Are Big Fan Leaves a Good Sign?

Large fan leaves are an excellent indication of health of the cannabis plant. It often lets the growers know that the plant has been receiving adequate light and nutrition during the vegetative stage! The larger the leaves, the more photosynthesis and transpiration the plant is capable of, which leads to faster and more robust growth!

However, the size of the fan leaves can vary depending on genetics and chosen strain. Some strains will produce larger and differently shaped leaves than others.

Although large fan leaves are a sign of good health and strong vegetative growth, it does not directly correlate to to the plant's potential to produce large and high quality yields. If you're expecting an abundant harvest, it's essential to consider the other factors as well, such as:

  • overall health of the plant;
  • nutrition, and;
  • environmental conditions.

Fan Leaves vs Sugar Leaves

fan leaves vs sugar leaves

Fans leaves are the larger, more prominent leaves on the cannabis plant. They contribute to essential functions, like photosynthesis and transpiration. Fan leaves also provide shade and act as protection for more delicate parts of the plant. For the reason fan leaves are often trimmed or pruned away to expose the entire plant to light!

Sugar leaves are much smaller and are usually nestled in between sections of the flowers. They are named "sugar leaves" for their appearance, as these leaves can be covered in trichomes, giving them the look of being covered in sugar granules!

Sugar leaves often contain much higher amounts of cannabinoids than fan leaves, and aren’t often trimmed away or pruned like fan leaves are! Sugar leaves are eventually removed in the final trimming process, and the trim is often used in extracts or cooking!

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What If My Fan Leaves Turn Yellow During the Veg Stage?

As previously mentioned, fan leaves act as an indicator for the plant wellness! Yellowing or discoloration of fan leaves is usually a clear sign that there is an issue in the plants nutrition, typically a nutrient deficiency, toxicity, or PH imbalance.

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