Best Bloom Booster for Growing Cannabis

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For growers, one of the most significant growing times is during the flowering stage. In fact, right after plants leave the vegetative stage, they go into the flowering stage.

At that time, buds begin to develop and grow. During the initial period of the flowering stage is when your plants need to start a new nutrient application for healthy growth.

Oftentimes growers will use a bloom booster or bud booster to encourage big buds. Bloom booster is a complete fertilizer that has been specially articulated to deliver extra nutrients to the plants during the flowering phase.Β 

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The truth is, all growers want a bigger harvest. One of the best ways to achieve a better harvest is by having more buds.

Bloom boosters help the plants grow more buds as well and encourage the buds to be bigger and more dense.

The Best Bloom Boosters for Cannabis

Just like people, your plants need the right and proper amount of nutrients to be healthy. They need certain essential nutrients in order to grow.

These nutrients can be provided by feeding your plant fertilizer such as bloom booster during the flowering stage. Just like other types of fertilizer, bloom boosters come in a variety of brands and types.

Actually, you need to be very careful not to get the wrong bloom booster for your plants. To make it easier, here are the top bud and bloom boosters to fit your growing needs.

Big Bud Liquid Fertilizer

Advanced Nutrients GL525050-12 Big Bud Liquid Fertilizer is a renowned bloom booster among growers. It provides optimum bud growth for maximum potency capacity.

This excellent formula contains the perfect amount of phosphorus and potassium plus L-amino acids for bigger buds and higher yields.

The Advanced Nutrients GL525050-12 Big Bud Liquid Fertilizer is also easy to use, improves bud flavor, and is economical.


  • A renowned brand
  • Correct N-P-K ratios for large and heavy flowers
  • Works great is soil, hydroponics, and diluted foliar feeding


  • Some consumers say their plants attracted bugs and easily dried up

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Jacks Classic No.1.5 10-30-20 Blossom Booster

J R Peters Inc. 51024 Jacks Classic No.1.5 10-30-20 Blossom Booster Fertilizer is a specialized formula designed to increase the production of flowers. It feeds through both the roots and the leaves for optimal nutrition.

In addition, it contains the ideal N-P-K at 1:3:2. The J R Peters Inc. 51024 Jacks Classic No.1.5 10-30-20 Blossom Booster Fertilizer is great for the vegetative and fruit stage.

In addition, it can be utilized as a transplant solution.


  • Offers optimum nutrients
  • Is water-soluble within a few seconds
  • Provides healthier plants, and bigger blooms


  • The soil needs to be tested before you use the fertilizer

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Flower Fuel 1-34-32

Flower Fuel 1-34-32 is a superior bloom booster best for hydroponic growing. It is made from top-quality ingredients that help produce the largest and most flavorful crops imaginable.

In fact, the fertilizer contains optimum nutrients for a bigger and better harvest. Basically, Flower Fuel 1-34-32 encourages your plants to absorb organic compounds and essential nutrients at a quicker rate.

It contains an exclusive mix of vitamins, chelating agents, phosphorus, potassium, and hormones. As a result, you have high performance and bigger yields.


  • Cost-effective
  • Extremely soluble and dissolves in water quickly


  • Some consumers say they had uncontrollable pH spikes

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Fox Farm Trio Soil Formula: Big Bloom, Grow Big, Tiger Bloom

Fox Farm FX14049 Liquid Nutrient Trio Soil Formula: Big Bloom, Grow Big, Tiger Bloom is a trio set that consists of fertilizer for each stage of flowering – Tiger Bloom, Grow Big Hydro, and Big Bloom.

It is designed for optimum results in lavish greenery and enormous buds. In truth, Fox Farm FX14049 Liquid Nutrient Trio Soil Formula is one of the top bloom boosters on the market.

The fertilizer is extremely stable, simple, and affordable. It is perfect for hydroponics but it can also be used for soil or other methods of growing.

The trio provides simple solutions for the timing of fertilizer applications. It is ideal for both the novice and the expert grower.


  • Works well with both indoor and outdoor grows
  • Suitable for soil, hydroponics, or soil-less grow substrates
  • Contains a combo of grow big, tiger bloom and big bloom for perfect growth and bigger buds


  • Many consumers complained about the product not having a seal when deliver through Amazon

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Osmocote Smart-Release Flower & Vegetable

Osmocote 277960 Smart-Release Plant Food Flower & Vegetable is intended for strong root development and dynamic top-growth. In addition, it can feed up to 4 months, making it very convenient.


  • A renowned brand with numerous positive reviews
  • Great for all variety and types of plants, in all growing conditions
  • Has a slow release that feeds your plants up to 4 months or more


  • Some consumers recommend that you wear gloves and a mask when using the product

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Best Organic Bloom Booster

The Incredible Bulk bloom booster is certified organic and the best option if you want to keep your grow 100% organic.


  • Organic!
  • Small bag, good for small to medium size grows (1-4 plants)
  • High P-K ratio


  • New-ish brand: not a ton of reviews out there on effectiveness

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What is a Bloom Booster?

Whether you grow hydroponically, in the soil, or use coco coir, giving your plants fertilizer during the flowering stage is critical for health bud formation. Although there are many types of fertilizers available on the market, many experts agree that the best supplement for your plants is a bloom booster.

Bloom booster is a fertilizer that contains the essential nutrients for healthy plants during the last stage of development – the flowering stage. All bloom boosters are composed of two macro-nutrients

  • Potassium
  • Phosphorus
  • Nitrogen (sometimes)

In addition, bloom boosters will often contain micronutrients and other nutrients which can vary with each product or brand. Typically, bloom booster has a high middle fertilizer number – which is phosphorus. Some bud boosters also have higher potassium numbers.

The best N-P-K – nitrogen, phosphorus (phosphate), and potassium (potash) ratio for cannabis during the flowering stage is 1:3:2 for early to mid-bloom followed by 0:3:3 for late bloom. As a result, it is important to know what stage of flowering your plants are in.

A hand giving fertilizer to a young plant

Otherwise, you could over-fertilize and cause a drastic reduction in buds and their size. Some growers believe that the N-P-K ratio should be more balanced for bloom boosters.

As soon as your plants leave the vegetative stage, is when you start fertilizing. In result, to apply the right amount of fertilizer during this phase, it is important to know the different Cannabis Stages of Flowering.

All about Organic Fertilizers

Organic fertilizer is probably the most preferred bloom booster among cannabis growers. If fertilizer is labeled organic, then it is made of pure vegetable and /or animal waste.

In addition, some organic fertilizers contain minerals or sedimentary rocks like limestone, rock-dust, and gypsum. Organic fertilizer is typically composed of manure, compost, fish emulsions, worm castings, bone meal, and alfalfa.

These elements have many nutrients that feed the plant slowly, making it less likely of overfeeding. Organic fertilizer means that it does not contain anything that is man-made.

In addition, the ingredients are sustainable and Eco friendly. In truth, organic fertilizer has many benefits for the expert and novice grower


  • Better for the environment
  • Healthier for the consumer
  • Creates a better quality soil
  • Encourages water retention and better airflow
  • Holds organic matter and reduces nutrient runoff
  • Helps with water retention and airflow with recurrent use
  • Slow-release of nutrients; protect your plants from overfeeding and burn

There are also disadvantages in using organic fertilizer


  • More expensive
  • Can host more pests
  • Microorganisms break down at a slower rate with cooler temperatures

What are Synthetic Fertilizers?

Synthetic fertilizers for bloom boosters are comprised of chemical nutrients that are specially made to have precise concentrations of nitrogen, phosphorous, and potassium. These nutrients are absorbed quickly, which allows you to easily adjust the concentrations to fit the needs of the plants.

As well, synthetic fertilizers support the ability to adjust the nutrient content by either raising or lowering the concentrations. Although synthetic fertilizers are more affordable than organic fertilizers, they are not necessarily the most cost-effective solution.

In fact, synthetic fertilizers do not feed your soil by increasing the quality over time. In addition, synthetic fertilizers have a tendency to reduce the overall quality of your soil.

Hand full of small fertilizer

Like organic fertilizer, synthetic fertilizers have their advantages and disadvantages.


  • Cost-effective
  • Very versatile
  • N-P-K ratios are specific
  • Nutrient absorption is faster


  • Not very Eco friendly
  • It does not build a sustainable soil
  • Easy to burn and overfeed your plants

What Nutrients Does Cannabis Need to Grow?

Like most plants, cannabis needs certain nutrients to grow and be healthy as well as produce larger buds. The ideal nutrients for cannabis are nearly the same as many flowering plants.

These nutrient requirements make it a lot easier to select the proper bloom booster for your plants. In addition, most fertilizers contain the essential nutrients for lush plants – nitrogen (N), phosphorus (P), and potassium (K) or P-N-K.

  • Nitrogen (N) – is a significant component of chlorophyll which is generated to absorb energy from light; known as photosynthesis. Nitrogen is also a key element for amino acids to assist with building protein. Cannabis needs a higher ration of nitrogen during the vegetative stage.
  • Phosphorus (P) – helps normalize and regulate protein synthesis by utilizing complex nucleic acid compounds. It assists in developing new tissues and is crucial for cell division. Basically, phosphorus helps deliver energy to where the plant needs it the most. During the flowering stage is when the amount of phosphorus is increased. In fact, it takes energy to the buds, to the root system, and helps create more flowers.
  • Potassium (K) – this amazing element helps control the CO2 applications by opening and closing the stomata throughout photosynthesis. In addition, it triggers growth enzymes and is important to nutrient, water, and carbohydrate absorption. During the flowering stage, potassium is typically increased.

Knowing what N-P-K is and how to apply it for optimum growth is crucial for higher yields. In fact, not knowing what nutrients to use and when, can cost you a lot of money, time, and frustration.

However, there are certain Cheap Hydroponic Nutrients for Growing Weed that are quite beneficial for growers. Once you get to know what nutrients your plants need for the vegetative and flowering stage, it will be the biggest step towards higher yields.

Minor and Micro-Nutrients

The main nutrients for fertilizer are N-P-K. However, there are other nutrients that can be very beneficial for your plants such as minor and micronutrients.

Minor nutrients include

  • Calcium (Ca) – helps regulate the cells and maintains plant stability. Calcium also helps develop the cell walls.
  • Magnesium (Mg) – is a big factor in chlorophyll. It is the micronutrient that processes sunlight.
  • Sulfur (S) – sulfur is utilized to help form proteins, amino acids, and oils. It is also important for activating numerous enzymes and vitamins.

The micronutrients are vital for health but only needed in small amounts. These seven elements include iron (Fe), manganese (Mn), zinc (Zn), boron (B), molybdenum (Mo), nickel (Ni), copper (Cu), and chloride (Cl).

Is Bloom Booster the Same Thing as Bud Booster?

Yes, bloom and bud boosters are the same thing.

Some people call them bud boosters because the plant forms the buds during the bloom phase.

Do Bloom Boosters Work?

Bloom or bud boosters supply and enrich your plants with phosphorus and potassium plus other nutrients such as calcium, magnesium, and sulfur during the late stages of growth. This the crucial time for feeding your plants in order to get optimal results.

In fact, every macronutrient supports a certain aspect of flower development. It is important to know which bloom booster is best for your plants.

Best Bloom Booster for Growing Cannabis

You don’t want to go to the nursery or feed store and buy just any bloom booster off the shelf. Even bud boosters have different N-P-K ratios.

Actually, it is extremely important that you buy a bloom booster made specifically for the plants you are growing. You want to ensure that your plants get the proper ratio of nutrients for the best growth and yields.