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Cultivation processes often receive meticulous attention from those who work with hemp, from seed selection to care during flowering. However, once the harvest is over, there are still critical stages that can determine the final state of the flowers: drying and curing. Not only are these moments essential for preserving texture and aroma, but they also represent a time when they need to be taken care of from diseases and silent enemies, such as botrytis. This fungus, also known as gray mold, can develop even after the cbd buds have been harvested and stored. The presence of internal humidity, combined with unsuitable environmental conditions, can trigger its appearance and ruin the entire crop. Understanding how to eliminate botrytis in dried buds requires a thorough understanding of its causes, its signs, and the strategies that allow it to be controlled before it compromises an entire harvest. Below, we’ll look at the aspects that growers take into account to prevent this common threat in their CBD flower crops. What is botrytis and how does it affect dried buds? Botrytis, commonly known as gray mold, is one of the most persistent silent enemies in the world of hemp cultivation. This pathogenic fungus has the ability to appear at different times of the process, from flowering to even after drying, when everything seems to be under control. In the case of already dried buds, their presence can be especially frustrating, as it affects flowers that had apparently passed all the critical stages of cultivation. The development of gray mold on dried flowers not only has aesthetic implications, but also compromises their integrity. Grayish spots, loss of firmness, and a musty odor are some of the most obvious indicators. According to recent scientific observations, this fungus does not need much to activate: it is enough for certain internal conditions to be generated within the bud for it to find a favorable environment and begin its expansion (Buirs et al., 2025). Characteristics of gray mold Botrytis cinerea is an opportunistic fungus. This means that it can lie dormant for days or weeks, giving no sign of its presence, until it detects enough moisture and heat to start growing. In studies on greenhouse cultivation, it has been observed that the most critical days for its appearance are between the fifth and sixth week of flowering. During this period, the inside of the buds usually registers higher temperatures and humidity levels than the general environment, thus favoring their appearance. Infected flowers lose their firmness, acquire a soft or brittle texture, and in some cases may show a thin, cottony layer of gray. This aspect is not only a visual issue: botrytis directly alters the structure of the flower, weakening its tissues and reducing its ability to preserve. Conditions that favor their appearance The appearance of botrytis does not occur randomly. There are a series of environmental and physical conditions that, when they coincide, create the perfect scenario for its development. The first key factor is residual moisture. Even if the drying appears complete on the surface, the inside of the flowers can still retain water, especially in particularly dense varieties. In fact, it has been recorded that the relative humidity inside the bud can be up to 15% higher than in the outdoor environment, and the internal temperature can increase 2.5°C above that of the greenhouse. This hot, humid microclimate is not easy to spot with the naked eye, but it creates a stable environment for botrytis spores to activate. Poor ventilation also plays an important role in this process. In spaces where air does not circulate fluidly, pockets of moisture form that, when trapped between the buds, serve as a starting point for infection. These situations are usually exacerbated during the summer and early autumn months, when outdoor conditions tend to be milder and wetter. That is why environmental control is essential during all moments of the process, even in the post-harvest stage. Small variations in humidity and temperature can trigger major problems if not identified in time. Common mistakes that increase risk The appearance of botrytis in dried buds is not always due to external causes. In many cases, certain errors during the handling and conservation of flowers can favor their appearance, even when the cultivation has been successful up to that point. This section discusses some of the practices that, although common, can generate conditions that activate the presence of the fungus. Improper or accelerated drying The drying process is a delicate stage that requires patience and control. When flowers are exposed to excessive heat or overly aggressive ventilation, the outer surface can dry out quickly, giving a false sense that the process is over. However, the inside of the bud can still retain moisture, and that internal difference becomes a risk factor. Over time, that trapped moisture can promote fungal formation, even weeks after drying. In addition, hasty drying can damage the flower’s natural aromatic and volatile compounds, reducing its integrity both in terms of preservation and quality. Failure to trim or cure Manicuring, i.e. the removal of small leaves around the bud, also influences the development of botrytis. If it is done very superficially, plant remains may remain that store moisture. On the other hand, if it is done too aggressively, the flower is directly exposed, facilitating its dehydration and weakening its structure. During curing, airtight storage without proper regular ventilation can cause moisture released by the bud to be trapped. This internal condensation generates the exact environment that botrytis needs to activate. That is why controlled aeration during the first few weeks is so important: it prevents unbalanced internal conditions from forming and protects the flower from possible infections. How to detect botrytis in dried buds One of the biggest difficulties associated with botrytis in dried flowers is that it is not always detected immediately. In the initial stages, the signs are discreet and can be mistaken for normal variations in appearance. The change in texture is usually one of the

Under certain conditions, even the best-preserved flowers can show unexpected signs of decay. Sometimes, what starts as a small change in the color or texture of the buttons turns out to reveal a deeper problem. What factors cause a CBD flower to turn brown? What can it mean? The brown, dry appearance that sometimes appears is not a simple aesthetic issue. In this article, we explore how the environment, harvesting processes, and certain diseases affect bud health, and what measures growers use to help preserve their optimal state. Why do some buds turn brown and dry? The transformation of fresh, compact buds into brown, brittle structures can be a cause for concern, considering that in hemp, visual and structural quality is a key indicator of good conservation. Although certain varieties are naturally darker in color, the unwanted change to a dull brown hue, accompanied by stiffness or brittleness, is often associated with problems. Understanding which processes are involved in this degradation is the first step to keeping flowers healthy and preserving their characteristics. Environmental Factors: Humidity, Temperature and Ventilation In any growing space, environmental conditions act as fundamental pillars that support the vitality of flowers. When humidity levels are high and ventilation is poor, the environment becomes conducive to fungal growth. On the contrary, very dry environments cause the buds to dehydrate quickly, losing their elasticity and becoming fragile. Temperature also has a significant influence. Excessive heat accelerates the loss of water and volatile compounds that contribute to the natural consistency of flowers. On the other hand, cold temperatures during flowering can slow down the overall development of the plant. Together, these factors are the key that will determine the appearance, texture, structure, and overall quality of the buds. Common mistakes in drying and cutting Once the harvest is finished, the next challenge is drying, a delicate process that directly influences the appearance and preservation of the flowers. If done in improper conditions, with excessive ventilation or high heat, buds can dry unevenly. This generates a hard surface while the interior retains moisture, which favors the appearance of mold as the days go by. Cutting, i.e. the removal of small leaves around the flowers, also has important implications. If done superficially, plant debris may remain that retain moisture or make it difficult to cure evenly. At the other extreme, excessive cutting can leave the buds too exposed, facilitating premature dehydration. The key is to find a balance that ensures good presentation and proper storage. Diseases and pests that affect appearance The health of flowers can also be affected by biological factors, such as fungi and insects, which alter their color, texture, and structure. Early identification of these threats makes it possible to take effective action before irreversible damage occurs. Botrytis: Grey mould on the buds Botrytis, also known as grey mould, often affects buds during the final stage of cultivation, especially when humidity and ventilation conditions are not well controlled. This fungus can develop silently, with no visible signs, until flowering progresses and the microclimate inside the bud becomes warmer and more humid. According to a recent study carried out in greenhouses, the most critical moments for its appearance coincide with advanced flowering stages. During this period, the humidity and temperature inside the buds exceed those in the environment, creating the perfect environment for the disease to become active (Buirs et al., 2025). The constant movement of the air and the choice of less dense varieties for the months or wetter spaces are key factors that help to reduce its impact. Other fungal infections: powdery mildew and Fusarium In addition to gray rot, there are other fungi that directly affect the quality of the buds. Powdery mildew usually manifests as a white, powdery coating on leaves and flowers. Although it may seem harmless at first, this layer blocks the process of photosynthesis, gradually weakening the plant and affecting the overall health of the flowers. Fusarium, on the other hand, acts more invisibly. It attacks the roots and stems, causing a kind of progressive wilting. Often, affected plants appear to drooping for no apparent reason until the root system is checked. This infection is also linked to conditions of excessive humidity and poorly aerated substrates. Preventing their appearance involves paying attention to drainage and maintaining controlled conditions at the base of the crop. Common pests: mites and thrips Small insects can also cause buds that appear dry, damaged, or discolored. Among the most common are mites and thrips, which feed on plant sap, leaving small spots, discolorations or fine cobwebs on leaves and flowers. When these pests attack the buds, they not only alter their appearance, but also weaken the overall structure of the flower, making it more susceptible to dehydration. Some natural methods of control include introducing beneficial insects, using potassium soap, and regularly cleaning the environment. Maintaining a clean and well-managed environment often makes all the difference in preventing this type of damage. Prevention strategies to maintain quality Throughout the entire process, from the vegetative stage to harvest, maintaining stable conditions is essential to preserve the integrity of the flowers. During the warmer months, especially in summer and early fall, plants can become more susceptible to deterioration, particularly those varieties with very dense or closed flowers. Avoiding extreme levels of humidity, strengthening ventilation in the growing space and opting for less compact genetics are decisions that can make a big difference in this critical period. The mid-flowering stages have also been observed to represent a window of increased risk, so it’s helpful to implement preventative measures before the plant reaches that point. The use of fans or exhaust systems helps maintain a steady flow of air, which prevents the formation of humid microclimates where pathogens can thrive. Likewise, avoiding waterlogging when watering and opting for substrates with good drainage improves the overall condition of the roots and, by extension, the entire plant. In addition, regular monitoring helps to detect possible imbalances in a timely manner. Through this preventive

Dry leaves around buds can be a sign of a variety of internal or external factors that alter the structural health of the flower. Although in some cases it is a natural process during advanced stages of flowering, its excessive or anticipated presence is often linked to imbalances in the growing environment. For growers, understanding the possible causes behind this phenomenon and how to prevent it can make all the difference in the final development of CBD flowers. Irrigation and nutrients in hemp crops In this section we address two of the most determining factors for the hydration and nutrition of flowers: watering and the use of fertilizers. When not properly managed, they can trigger visible signs such as drying leaves, starting with the areas near the bud. Underwatering or overwatering of the roots One of the most frequent triggers of premature drying of leaves is improper irrigation management. When the substrate remains dry for prolonged periods, water stress occurs, which disrupts essential processes such as photosynthesis. As a result, the leaves near the bud may lose firmness, have brittle edges or take on a brown colour. This dryness not only affects the visual appearance, but also compromises temperature regulation and the overall health of the plant. On the contrary, an excess of irrigation can lead to anaerobic conditions, that is, a lack of oxygen in the root zone. This situation hinders the absorption of nutrients, generating symptoms such as yellowing, leaf weakness and, over time, progressive drying of the foliage. Looking at the weight of the pot, the texture of the substrate, and the rate of absorption can offer clues as to whether watering is being balanced. Excess fertilizers and buildup in the substrate Another relevant factor is the excessive use of fertilizers. The overload of nitrogen, phosphorus or potassium, especially in sensitive phases of flower development, generates accumulations of salts in the substrate. This saturation prevents a balanced assimilation of minerals, which produces what is commonly called “nutrient burn”: a progressive necrosis that begins at the tips and edges of the leaves. This type of damage is usually first seen as a change in color, going from a deep green to a yellowish or brown hue. The affected tissue then dries out and becomes brittle. To avoid this, many people dedicated to cultivation choose to apply fertilizers in moderate doses, slightly below what is recommended by the manufacturers, especially in soils that have already been previously enriched. Environmental stress in hemp flowers In addition to water and nutritional management, environmental conditions can also directly affect the vitality of flowers and the appearance of nearby leaves. Two common factors are explored here: climate (temperature and humidity) and light exposure. Temperatures and humidity outside the recommended range Environmental conditions directly influence the appearance of dry leaves. Excessively high temperatures, coupled with too low humidity levels, often accelerate the dehydration of plant tissue. In these scenarios, leaf transpiration increases, depleting their water reserves more quickly and causing a visible loss of turgor. For example, in indoor spaces without climate control, an unexpected increase in temperature can generate a dry environment that forces the plant to release more water to stay cool. If this process is not compensated by adequate relative humidity, the leaves begin to deteriorate. This loss of water balance is especially visible in the leaves that surround the buds, due to their more exposed position. Excessive direct light on flowers or buds In addition to temperature and humidity, light intensity can have a direct impact on the most delicate leaves. Prolonged exposure to intense light sources, both indoors and outdoors, can cause what is known as light stress. The leaves that protect the buds, especially in the upper areas of the plant, tend to dry out when exposed unprotected at peak radiation hours or when the lamps are poorly positioned. This type of damage can be prevented by adjusting the distance between the lamps and the plant canopy in indoor systems, or by providing partial shade during the hours of strongest sun outdoors. This prevents burns from too much light and protects the structure of the flower. Pests and fungi that damage buds The growing environment can not only be altered by physical variables, but also by biological agents. Pests and fungal infections pose common threats that can manifest themselves in the form of dry or damaged leaves, affecting both their appearance and health. Visible signs on affected leaves and flowers The presence of insects or fungal diseases is directly related to the abnormal drying of the leaves. For example, mites such as spider mites affect the plant’s ability to transport water and nutrients evenly. Its damage manifests itself in the form of light spots that quickly turn brown and brittle. These signs usually appear first on the underside of the leaves and, if not controlled in time, can spread to areas near the bud. Another common case is that of mildew, a fungus that compromises the health of the foliage by covering the leaves with a whitish coating that prevents them from breathing properly. When this happens near the flowers, the impact is greater, as it interferes with the formation and density of the buds. Control and prevention with frequent monitoring In the face of this type of threat, the essential thing is to implement regular controls. Detailed observation of foliage with tools such as magnifying glasses and early detection of spots, fine cobwebs, or strange dusts can be the key to preventing worse conditions. In addition, many people use biological or preventive treatments with specialized products or even with other beneficial organisms. Maintaining the cleanliness of tools, avoiding contact between affected and healthy specimens, and ensuring constant ventilation are also part of the strategies to reduce the risk of infestations and fungal outbreaks. What to do if there are already dry leaves on the buds When leaf drying has already manifested, it is still possible to intervene to limit the damage and promote the recovery of