When to Switch to Flowering Nutrients For Your Cannabis

Switch your plants to a flowering fertilizer like Reefertilizer Bloom when switching to a 12/12 light schedule or after the summer solstice.

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When to Switch to Flowering Nutrients

The growth of a cannabis plant can be broken down into two basic stages: the vegetative stage and the flowering stage. You will need to pay close attention to your plants to know when to switch to flowering fertilizer at the beginning of the flowering stage.
Plants will have a short growth spurt then stop growing taller when the flower period begins. At that point, they’ll be focusing all of their energy on growing bigger, juicier buds. Typically, this happens around three weeks into the flowering stage.

When To Switch Indoor Weed To Bloom Nutrients

When you switch lights to 12 hours of darkness a day the plant will naturally go to a flowering state. A week after the switch is when you should start feeding plants Bloom fertilizer.

Click the image above to see a close up of the very early stages of flowering.

Those small white “hairs” are called pistils. The pistils emerge from a little pod called a calyx. The cannabis flower is made up of a cluster of these calyxes.

When To Switch To Flowering Nutrients Outdoors

Plants will normally begin to flower a few weeks after the summer solstice (June 20) as the days begin to get shorter. Look to the formation of flowers as a sign to switch to Bloom fertilizer.

When To Switch Autoflowers To Flower Nutrients 

These types of strains will flower automatically no matter how much light they’re getting daily. Autos typically start flowering after 3-4 weeks. Keep an eye out for new flowers and switch to Bloom fertilizer.

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Why Switching To Flowering Nutrients Is Essential for Growing Good Cannabis

Flowering nutrients play a critical role in cannabis growth by providing the specific elements plants need during the flowering stage. Unlike the vegetative phase, where nitrogen is key for leaf and stem development, the flowering stage requires higher levels of phosphorus and potassium.

Phosphorus supports the development of robust flowers by enhancing root strength and energy transfer within the plant. Potassium, on the other hand, boosts bud density and improves resistance to stress. Together, these nutrients ensure healthy flower formation, leading to larger, more potent yields.

Using the right flowering nutrients at the right time maximizes the plant’s genetic potential, ensuring a successful harvest with high-quality buds. Neglecting this can result in weak, underdeveloped flowers and lower yields.

Always choose nutrients specifically formulated for the flowering stage to meet the plant’s evolving needs.

Signs Your Cannabis Needs Flowering Nutrients

As cannabis transitions into the flowering stage, its nutrient requirements shift dramatically. Recognizing the signs that your plant needs flowering nutrients is crucial for maximizing yield and bud quality.

1. Slowed Flower Development: If buds seem small or are forming slowly, it may indicate a lack of phosphorus and potassium, essential nutrients for flower growth.

2. Yellowing Leaves: While some leaf yellowing is natural in late flowering, early yellowing may signal a nitrogen deficiency, common when plants start using stored nutrients.

3. Weak or Sparse Buds: Buds that are light, airy, or poorly developed suggest a lack of potassium, which is critical for bud density and strength.

4. Reduced Resilience: Plants become more susceptible to stress, pests, or diseases when flowering nutrients are insufficient.

By providing a balanced nutrient mix tailored to the flowering stage, you ensure the plant has everything it needs to thrive, producing dense, resinous buds.

How Often To Fertilize In Flowering Stage?

During the flowering stage, the frequency of fertilizing your cannabis plants can vary based on the specific requirements of the strain you are growing. Generally, it’s recommended to feed them with a flowering fertilizer blend about once per week. However, auto-flowering strains or those with particular nutrient sensitivities may require adjustments to this schedule. Always observe your plants’ response to the fertilizer; signs of nutrient burn may indicate that you should reduce the frequency or concentration of feeding. Additionally, stop all nutrient feeding in the last week before harvest to allow your plants to flush out any residual nutrients, improving the taste and quality of your buds.