Feeding Flowering Cannabis Fertilizer

Week 1-2 of Flowering

The plant is still in the early stages of flowering, so its nutritional needs are similar to those of the vegetative stage. However, the plant will start to require more phosphorus and potassium, as these nutrients are essential for flower development.

You can start feeding your plants a flowering fertilizer at this stage. A good flowering fertilizer will have a high phosphorus and potassium content, with a lower nitrogen content.

The amount of fertilizer you need to feed your plants will depend on the size of your plants and the type of fertilizer you are using. Be sure to follow the instructions on the fertilizer packaging carefully.

During weeks 1-2 of flowering, you should also pay attention to the following:

• Light: The plant will need more light during the flowering stage. If you are growing indoors, you may need to increase the amount of light your plants are receiving.
• Water: The plant will need more water during the flowering stage. Be sure to water your plants regularly, but do not overwater them.
• Temperature: The plant will prefer a slightly cooler temperature during the flowering stage. A temperature around 70-75 degrees Fahrenheit (21°C-23°C) is ideal.
• Humidity: The plant will prefer a slightly lower humidity during the flowering stage. A humidity of around 50-60% is ideal.

Best Practices

Here are some best practices for week 1-2 of flowering:

• Start feeding your plants a flowering fertilizer. A good flowering fertilizer will have a high phosphorus and potassium content, with a lower nitrogen content.
• Increase the amount of light your plants are receiving. If you are growing indoors, you may need to increase the light intensity or the number of hours of light your plants are receiving.
• Water your plants regularly, but don’t overwater them. Overwatering can lead to root rot and other problems.
• Monitor and track your plants closely. Pay attention to their growth and development, and make sure they are not showing any signs of nutrient deficiencies or pests, or diseases.
• Keep your grow space clean and free of debris. This will help to prevent the spread of pests and diseases.

If you are growing cannabis outdoors read our blog on the best nutrients for outdoor growth. 

Week 3-4 of Flowering

The plant is now in the early to mid-flowering stage. Its nutritional needs will continue to increase, and it will require more phosphorus and potassium than ever before. You should be feeding your plants a flowering fertilizer at full strength at this point.

During this stage, the plant will start to produce pistils (the female reproductive organs) and trichomes (the resinous glands that produce the cannabinoids and terpenes). The plant will also start to develop its buds.

To help your plants thrive during this stage, you should focus on providing them with the following:

• Potassium: Potassium is essential for flower development and bud growth. It helps to regulate the plant’s water uptake and transport, and it also helps to strengthen the plant’s stems and branches.
• Phosphorus: Phosphorus is essential for flower development and bud growth. It helps to produce energy for the plant, and it also helps to regulate the plant’s metabolism.
• Nitrogen: Nitrogen is still important during this stage, but it is not as important as phosphorus and potassium. Nitrogen helps to promote vegetative growth, so you should reduce the amount of nitrogen you are feeding your plants.

Best Practices

Sure, here are some best practices specifically for weeks 3-4 of flowering cannabis plants:

• Continue feeding your plants a flowering fertilizer. The plant will need more phosphorus and potassium during this stage, so you may need to increase the strength of the fertilizer.
• Monitor the pistils. The pistils are the female reproductive organs of the plant, and they will start to turn from white to orange or brown during the flowering stage. 
• Check the trichomes. Trichomes hold many cannabinoids and terpenes. The trichomes will start to turn from cloudy to amber during this stage. The amber trichomes are when the THC content is at its peak, but at this point, many will still be clear.
• Keep an eye out for mold. The cooler temperatures and increased moisture in late flowers can create a perfect environment for mold growth. Make sure to provide your plants with adequate ventilation and airflow to help prevent mold.
• Defoliate your plants. This will help to improve airflow and reduce the risk of mold growth.

Beware of the smell. Your plants might be very fragrant and they’re only going to get stronger. If your growing indoors a carbon air filter can be very helpful. Growing outdoors, strong flowers like lilac can help mask the smell.

Week 5-6 of Flowering

The plant is now in the mid-to-late flowering stage. Its nutritional needs won’t taper off, as the plant is now focused on producing flowers. You can continue feeding your plants a flowering fertilizer.

During this stage, the plant will continue to develop its buds. The buds will start to swell and fill out, and the trichomes will start to mature.

To help your plants thrive during this stage, you should focus on providing them with the following:

• Potassium: Potassium is still essential for flower development and bud growth. It helps to regulate the plant’s water uptake and transport, and it also helps to strengthen the plant’s stems and branches.
• Phosphorus: Phosphorus is still important during this stage, but it is not as important as potassium. Phosphorus helps to produce energy for the plant, and it also helps to regulate the plant’s metabolism.
• Nitrogen: Nitrogen is not as important during this stage, so you can reduce the amount of nitrogen you are feeding your plants.

You can feed your plants a flowering fertilizer at half-strength during this stage. Be sure to follow the instructions on the fertilizer label carefully.

Best Practices

Best Practices for Week 5-6 of Flowering Cannabis Plants:

Feeding:

• Peak flowering time: Week 5 and 6 are critical for maximizing flower development, so closely monitor your plants during this period.
• Nutrient balance: Check for signs of nutrient deficiencies or overfeeding. Adjust nutrient levels accordingly for optimal growth.
• Increased calcium: Flowering plants have higher demands for calcium, which is essential for strong cell walls and overall plant health.

Stress:

• Avoid stress: Minimize any stress factors to prevent stunting bud growth or triggering hermaphroditism.
• Hermaphroditism risk: Stress can cause female plants to produce pollen and self-pollinate as a last-ditch effort to reproduce before the end of their life cycle.
• Avoid light leaks: If you’re growing photoperiod plants indoors it’s very important that the plants are getting 12 hours of complete darkness every day. A small amount of light can mess with your plant’s sense of time and trigger it to go back to it vegetative stage.

Support:

• Provide support: Fresh cannabis flowers can become quite heavy, potentially causing branches to bend or break. Use bamboo stakes, strings, or plant clips to keep plants upright and support heavy buds.
• Prevent tumbling: Proper support prevents plants from falling over, which can damage flowers and affect overall yield.

Humidity and Temperature:

• Maintain humidity: Keep humidity levels between 30–40% to prevent issues with mold or pests that thrive in high-humidity environments.
• Daytime temperature: Maintain daytime temperatures at a maximum of 25°C to ensure optimal flower development.
• Nighttime temperature: Keep nighttime temperatures around 16–17°C to create a favorable environment for flowering cannabis plants.

Week 7-8 of Flowering

The plant is now in the late-flowering stage. Its nutritional needs are still high, as the plant is now focused on ripening its flowers. You can make the decision on whether or not you want to flush the plants before harvest. 

However, it is important to keep an eye out for any nutrient deficiencies that may occur during this stage. Some common nutrient deficiencies that can occur during the flowering stage include:

• Magnesium: Magnesium is a key nutrient for photosynthesis, and a deficiency can lead to yellowing leaves and stunted growth. It is also involved in the production of chlorophyll, which is necessary for plants to absorb sunlight. Its deficiency can lead to yellowing leaves and stunted growth.
• Calcium: Calcium is important for cell wall development, and a deficiency can lead to bud rot and other problems. It is also involved in the transmission of signals between cells.
• Boron: Boron is important for cell division, and a deficiency can lead to stunted growth and deformed flowers. It is also involved in the transport of nutrients within the plant.
• Copper: Copper is important for enzyme function, and a deficiency can lead to stunted growth and poor flowering. It is also involved in the production of melanin, which gives plants their color.
• Iron: Iron is important for chlorophyll production, and a deficiency can lead to yellowing leaves. It is also involved in the production of energy within the plant.
• Manganese: Manganese is important for photosynthesis, and a deficiency can lead to yellowing leaves and stunted growth. It is also involved in the production of antioxidants, which protect plants from damage.
• Zinc: Zinc is important for enzyme function, and a deficiency can lead to stunted growth and poor flowering. It is also involved in the production of proteins, which are essential for plant growth.

If you suspect that your plants may have a nutrient deficiency, you can test the soil or leaves to determine the levels of nutrients present. When you’re this late in the game it might not be that important to try and cure every deficiency you see. This late in the plant’s lifecycle it will begin using up nutrients in older leaves and begin shedding those leaves. This is totally normal for a cannabis plant.   

Best Practices

Nutrient Flush

• Timing: Initiate the nutrient flush two weeks before your planned harvest date to remove excess nutrients from the soil.
• Flushing benefits: Flushing improves the overall taste, aroma, and smoothness of the final product, as well as reducing the risk of harsh, chemical flavors. Some folks believe the difference is minimal.

Humidity

• Maintain low humidity: Keep humidity levels between 30–40% to minimize the risk of mold and pests during the final stages of flowering.
• Proper ventilation: Ensure proper air circulation in the growing area to prevent moisture buildup and potential mold issues.

Bud Maturity

• Observing trichomes: Continuously monitor your plants during the two-week flush period. Use a magnifying glass to check the trichomes (resin glands) on the buds.
• Trichome method: Harvest when trichomes appear cloudy or milky and some are amber. This indicates peak cannabinoid content for the desired potency.

48–72 Hours of Darkness (Optional)

• Darkness before harvest: Consider implementing a 48–72 hour period of complete darkness just before harvest.
• Increased trichome production: Some growers believe this technique can stimulate the plant to produce more trichomes, leading to potentially more potent weed.
• Monitor carefully: Be cautious with this method as it can be stressful for the plant, and its effectiveness might vary depending on cultivar and growing conditions.

If you want to get the most out of your cannabis plants, then you need to be feeding them Reefertilizer Bloom.

How to Feed Your Plants Reefertilizer Bloom

Reefertilizer Bloom is a high-quality flowering fertilizer that is designed to help your plants produce big, dense flowers. It is a dry powder fertilizer that is easy to mix with water.

To feed your plants, Reefertilizer Bloom, simply follow these steps:

1. Mix the recommended amount of Reefertilizer Bloom with water in a clean container.
2. Water your plants as usual.

You can feed your plants, Reefertilizer Bloom, every time you water them during the flowering stage. The frequency of feeding may vary depending on the size and type of your plants.

Start feeding your plants Reefertilizer Bloom when you switch lights to 12/12 or when preflowers appear.

Feeding “Reefertilizer Bloom – flowering cannabis fertilizer” is essential for helping your plants produce big, dense flowers. Reefertilizer Bloom is a high-quality flowering fertilizer that is designed to help your plants reach their full potential. It is easy to use and provides all the nutrients your plants need to produce a bountiful harvest.

Here are some additional benefits of using Reefertilizer Bloom:

• It is made with chelated nutrients that are immediately available to plants
• It is safe for both plants and the environment when used as directed.
• It is easy to use and measure.
• It is affordable.