Humidity is crucial where cannabis plant health is concerned. It’s a measure of the amount of moisture vapor in the air, and it’s surprising how many growers overlook this important factor. Humidity prevents or facilitates water evaporation in plants.
If humidity is low, your plants will absorb more water and nutrients, because evaporation speed increases in a drier environment. With that said, dryness isn’t always a good sign. If evaporation is allowed to continue too fast for too long, it will put an enormous strain on a plant. The marijuana plant will close its stomata and slow evaporation, in turn stunting its own growth.
That’s why it’s important to monitor the humidity level in your growing environment at every stage in your crop’s growth. For instance, a plants’ flowering phase requires less humidity than is needed in the vegetative stage. The smaller a plant’s roots are, the more moisture it needs. The best way to measure a grow room’s humidity level is with a hygrometer; it should be about 70% in the beginning and it should drop by roughly 5% per week until it’s at 40%. Then, it can be safely kept at that level.
In this guide we’ll discuss:
Read on to learn how humidity affects the success of a cannabis crop.
There’s a strong correlation between humidity levels and temperature. A room’s temperature determines how much moisture the air can hold. When the temperature is at about 68° F, for instance, the air can hold about 7.2mL of water for 100% humidity. At a temperature of 32° F, the air will hold only about 5mL of water. That’s why the air is drier in the winter than in the summer. With the right indoor cultivation setup, ventilation won’t be an issue. Proper ventilation not only keeps the plants from gathering excess moisture, but it also releases airborne humidity.
Like seedlings, clones at first have small roots. They can’t absorb much water, and they should hold on to what little moisture they do take in. It’s crucial to slow the evaporation process, and to do it, you’ll have to maintain a high humidity level. 70% humidity is a great place to start.
If the indoor temperature is approximately 72° F and there’s fluorescent lighting and ample humidity, your cuttings will do well. If you’re using 600W HPS lamps, strive for a 30% humidity level. By following these guidelines, you’re more likely to produce strong, healthy plants.
A seedling functions a little differently than a clone cutting does. They absorb water rather quickly, considering their root size. Don’t remove any seedling leaves, as they’re crucial for light and water absorption. It’s a good idea to start out with 60% relative humidity (RH) and gradually reduce it to 40% RH.
During the flowering stage, your plants are at their most mature. Their roots can absorb more nutrients and water during this time. However, mold is a big concern, so you’ll need to keep the room at a low humidity level. The older a plant is, the more susceptible it is to bud rot and other forms of mold.
You can precisely follow these guidelines to ensure maximum growth and good plant health. Keep in mind, though, that seedlings and clones have different humidity requirements.
If you’re growing a garden indoors, it’s not too hard to increase the humidity level. It’s possible to start by spraying water on the walls and the flowers, but eventually, you’ll have to move the lights farther away from the plants to slow down evaporation. Another easy option is to purchase a humidifier, which turns water from a liquid into a vapor. You can also leave open water containers in the grow room.
As your plants enter their flowering stage, you’ll need to gradually decrease the humidity level. Extractor fans work well for this purpose, as does dropping the temperature by bringing cold air in. To ensure reliable, consistent action, it’s best to use a dehumidifier. These machines turn water vapor back into liquid and hold it or drain it away. A larger unit is preferable as it reduces the time spent checking and cleaning the holding tank.
Even with indoor gardens, outdoor humidity has certain effects. For instance, if it is rainy and warm, it may be good to slow down or turn off the extractor fan. Be sure to avoid sudden temperature spikes.
As mentioned previously, you can measure your room’s humidity with a hygrometer. Simply place it above your crop in a well-ventilated location. Hygrometers are inexpensive, ranging from $5 to $10, and wired units work best because you won’t have to turn on a light to check the humidity level. These units monitor levels over time so you can easily track humidity highs and lows.
Humidity is a long-standing factor in the agricultural process, and cannabis cultivation is no exception. Though it’s most closely linked to temperature-related problems, humidity’s effects are just now getting the recognition they deserve. When growing cannabis, humidity control methods vary widely.
The most crucial thing to focus on when buying dehumidification equipment is its efficiency. The most straightforward measurement of a unit’s efficiency is its energy consumption/water removal or cost/water removal ratio.
Unsurprisingly, water leads to humidity increases. During your crop’s growth stage, this isn’t an issue. However, as the plants bloom, it may present a problem. To minimize humidity increases, only water the plants when the grow room’s lights are on, so the water evaporates faster. Avoid spraying the buds, as it may lead to bud rot.
If you’re cultivating cannabis outdoors, there’s little to worry about as far as outside humidity is concerned. You’ll naturally get more moisture when the plants need it, and the humidity level will drop when light and temperature are decreasing during the plants’ late-summer flowering stage.
With that said, at the end of the summer there may be enough morning dew to cause mold growth. Therefore, when you’re checking your crop in the morning, it’s important to remove as much of the dew as possible. If you can easily move the plants, try to plan so they’re kept out of the rain.
The right humidity level for auto-flowering cannabis strains depends on several environmental factors. Plants should be kept at a relative humidity of 40% – 70% during the pre-flowering stage; any higher than that, and the plants may suffer. Water in the stems and leaves won’t evaporate at such high humidity levels, which will stunt the plants’ growth.
Because pre-flowering is such an important time for auto-flowering strains, it’s crucial to maintain an ideal humidity level. You’ll have to regularly adjust the humidity as the plants begin to flower, as high moisture will increase the chances of mold growth and plant infection.
Excessive moisture causes mold to grow in these plants’ dense buds. If you’re not careful, the mold will spread quickly. Mold is virtually undetectable during the pre-flowering and flowering segments, but it quickly spreads throughout the plant. Without quick action, an infected plant may not be salvageable.
Like all other plants, cannabis plants adjust their stomatal openings based on air humidity and VPD (vapor pressure deficit). High humidity is a real problem because it inhibits the plants’ absorption of water, compromising the crop’s quality. Similarly, if humidity is too low and transpiration is elevated, the plants will close their stomatal openings to prevent wilting. However, this slows photosynthesis and overall growth.
As briefly mentioned above, the two functions that are closely related to airborne humidity and crop performance are photosynthesis and transpiration. We’ll discuss these factors in the sections below.
Conversely, if the air is humid, a plant won’t take in much water from the soil, which means it won’t absorb much fertilizer, either. This poses quite the problem, as inadequate intake of certain elements will cause nutrient deficiencies. Furthermore, low water absorption is linked to high growth medium pH, which limits the availability of micronutrients. Typically, such problems are encountered during winter and in early spring, when outdoor temperatures are low. They can also occur during the hottest, humid parts of summer.
It’s essential to maintain a constant humidity level in an indoor growing environment, but it shouldn’t be so humid that it approaches the dew point. If temps are at or right below the dew point, the air can’t hold moisture and condensation will build, covering leaf surfaces. When there’s water on a plant’s leaves, it greatly increases the chances of disease while inhibiting water and nutrient uptake.
Sometimes it’s difficult to maintain a temperature that’s above the dew point, especially during the winter when there’s not much air exchange. Dripping is a concern even when the relative humidity is enough, as it increases the risk of disease and leads to uneven drying. The use of heaters and fans helps, but there may still be enough humidity to cause condensation. Infrared heating systems may reduce condensation because they increase the temperature of surfaces such as plants and growing media, but they don’t affect the air.
If you’re planning to cultivate cannabis for personal or medicinal use, there are a few things to keep in mind, such as air conditioning, lighting, and humidity control. By monitoring these factors, you’ll ensure adequate airflow and maintain greater control over your cultivation effort. Not only will you maximize the overall yield, but you’ll also minimize threats from pests and disease. Most new growers know how to control room temperatures, but they often struggle to maintain the right relative humidity. Here are a few tips for indoor humidity control.
Many times, growers assume that they’ve perfected their indoor humidity control strategies. However, when they find that the grow room’s relative humidity is too high, those thoughts are dispelled. By following these tips, you’ll find it easier to keep your indoor garden room at the right humidity level for optimal growth.
It’s important to remember that plants will transpire about 97% of the water absorbed. Therefore, it’s crucial to buy the right size dehumidifier so it pulls enough moisture from the air. If you have a large indoor garden, you may need multiple dehumidifiers. Design your system so that if a unit malfunctions, the others will continue working. It may seem costly at first, but this strategy will help you save on power when compared to the use of a residential dehumidifier.
Even if your climate is ideal for cannabis cultivation, you’ll still have to balance your electricity usage and your spending to adequately control humidity. Proper climate control is crucial in a marketplace where marijuana prices are dropping but energy and labor costs are on the rise. Here are three easy tips to control humidity in your outdoor growing environment.
There’s more to humidity than what’s happening in the cultivation area. Ambient humidity is the moisture encountered outside your grow room or outdoor garden. In an air-conditioned space, the humidity level stays around 30% because the air conditioner removes most of the moisture from the air. In heated areas, the humidity may be even lower as the heating unit removes more moisture.
In the time it takes to prepare buds for consumption, they may lose a substantial amount of moisture. Without a good way to adjust and monitor humidity in the growing and storage area, your buds will dry out too quickly. When storing your prepared cannabis, a humidity control product will allow you to quickly replace lost moisture in buds and in the air, so you’ll enjoy consistent quality every time.
If you want a high-quality cure, it’s important to store your harvested crop in an area with a relative humidity that’s in a favorable range. Again, a humidity control product will help you maintain the ideal humidity level inside your storage area. From there, the biggest concerns are light and temperature. A good humidity control system will adjust levels based on changing temperatures, but it’s still important to keep your harvested cannabis flowers away from high heat. This prevents decarboxylation and minimizes the activation of cannabinoids. As many in the cannabis sector suggest, store your buds in a dark, cool place.
Though you’ll have to consider many factors as a cannabis cultivator, humidity is one of the most important. With too much humidity, your crops will suffer from bud rot, mold, and other diseases; with too little moisture, they may wither and die. With the tips in this guide and a functional humidity control system, it’s possible to grow a green, lush, and flavorful crop. Check out some tasty strains at i49.net!