Cannabis Science


What are the Best Bud Hardeners for Marijuana?

Have you ever grown a marijuana plant that was supposed to be the bomb, only to end up with less than desirable colas of fluff? Instead of dense, firm buds, the flower was light and airy with no weight. On top of that, there was hardly any smell or taste, and the effects were subpar, to say the least.

Several factors can contribute to this unfortunate outcome. Indeed, environmental conditions can play their part. Temperature, humidity, and airflow must be in sync, while the right nutrient recipes and training techniques must be applied, depending on the cannabis plant’s growth stage.

Stable genetics from recognized cannabis breeders is also a significant influence. Tried and true marijuana cultivars deliver expected results of cannabinoid and terpene levels, height and weight expectations, and how to grow info. Unfortunately, even if you have the best genetics in the world, the plant may still not produce big, bodacious buds if it does not receive the essentials for growth.

Healthy plant development requires feeding a well-rounded diet of the big three base nutrients, NPK, the secondary element support of calcium, magnesium, and sulfur, and essential micronutrients. However, different life stages command different formulations of nutrient programs to capitalize on growth advancement.

As buds begin to set in the flowering stage, growers can help the marijuana plant push energy flow into flower development by implementing bud hardeners. These extra additives target flower structure and composition, resulting in the rock-hard bud cannabis connoisseurs expect.

In this article, we’ll look at some of the best bud hardeners for marijuana growing and see what makes each product unique. These formulas range from soil organic inputs that feed the microbial world to synthetic bloom food enhancers for a hydroponic or soilless substrate.

But first, let’s take a look at what a marijuana plant needs to build a solid cola structure during peak flower time.

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Building the Buds for Heavy Colas

While outside cannabis growers rely on nature to oversee environmental conditions, indoor growers have the advantage of controlling much of the activity within a grow room. If they want to flip a vigorous marijuana strain from veg into the flowering stage, a simple switch to a 12-12 light schedule and aN HPS bulb(unless it is being grown under led grow lights), triggers photoperiod cannabis strains to refocus plant growth.

At this junction, marijuana plants undergo considerable transformations during reproduction. They double in size in the expansive pre-flowering growth stage while small, white pistils begin emerging as bud-sites establish on limbs and branches.

To help the plant redirect energy flow into bud formation, adjustments in NPK ratios encourage the cannabis plant to change course. However, nitrogen is a heavy player in vegetative growth, inputs of this nutrient need to be dialled back considerably in the flowering phase. Phosphorus and potassium are required during all cannabis plant life cycles but are hard-hitting driving forces in flowering plants.

Secondary plant nutrients calcium and sulfur are immobile, meaning they don’t move around within the plant. Most trace elements such as zinc, iron, boron, and manganese are immobile as well. A good flower recipe will replenish these essential nutrients frequently as they perform their specific duties in plant growth.

As the flower nutrient regime shows signs of building a solid base of cola development with nice sized, thick bud structure, introducing a flower hardener into the nutrient program will help the plant ‘thicken up.’ Many bud hardening formulas contain a blend of nutes, including inputs that encourage the building block formations of proteins, amino acids, and essential oils.

So, with a good idea of what a cannabis plant needs to build a heavy, dense bud structure, let’s take a look at some of the commercial options available on the market today.

Best Bloom Booster for Organics

BioBud by General Organics

General Organics’ BioBud product is a bloom booster that uses a plant-derived vegan approach in their formula. With an NPK ratio of 0.5 – 0.1 – 1.0, the big shot of potassium sends added support to Bulk up developing buds. This product also contains a small amount of the trace mineral molybdenum, an essential component for enzyme activity to increase nutrient uptake.

Derived from plant protein hydrolysate, rock phosphate, and sea kelp, BioBud stimulates expansive flower production with organic inputs. The formula encourages microbial activity to focus energy into bud development through bio-stimulants directed at fattening up the flowers. Application rates for BioBud are between ½ – 1 tsp/gal of water.

MaxiCrop Soluble Seaweed Powder

MaxiCrop’s Soluble Seaweed Powder builds flower density with this powerful 0 – 0 – 17 NPK formulation. Derived from Ascophyllum nodosum seaweed from cold Norwegian waters, this powder naturally feeds microbes with essential vitamins and minerals while encouraging enzyme activity.

The powerful potassium punch is a catalyst for carbohydrate metabolism encouraging glucose production. As the plant receives this big K boost, buds naturally become thick and dense with each feeding. At an application rate of one teaspoon per gallon of water, cannabis growers will save money with this handy powder.

Marijuana plant treated with bud hardeners

FoxFarm’s Big Bloom Liquid Plant Food

Big Bloom Liquid Plant Food by FoxFarm is a blend of organic inputs that include rock phosphate, sulfate of potash, and Norwegian Ascophyllum nodosum kelp. The product also contains high concentrations of worm castings and bat guano used to fortify flower production.

With a 0.01 – 0.3 – 0.7 NPK profile, Big Bloom encourages strong flower development and thick bud structure. This environmentally friendly organic bud hardener is formulated to produce dense, trichome-rich colas. Application rate recommendations vary between 2 – 4 Tablespoons per gallon depending on the growth stage.

Incredible Bulk Organic Bloom Booster by Growganica

Incredible Bulk is an eco-friendly, vegan bloom booster listed as OMRI approved for organic cannabis growers. With impressive 0.1 – 10 – 25 NPK ratios, Incredible Bulk is a powerful punch of potassium to encourage energy transfer during the flowering stage.

Enzymatic activity and the formation of proteins and essential oils increase with the hefty dose of sulfur in this product. Additionally, sea kelp is included in this dry formula with its array of micronutrients, promoting densely packed buds. Recommended application rates start with ¼ tsp./gal and gradually increase to a maximum of 4 tbsp./gal.

Best Synthetic Bud Hardeners

Big Bud by Advanced Nutrients

Advanced Nutrients Big Buds is a popular bud hardener for hydroponic and soilless growers. With 0 – 1 – 3 NPK proportions, this formula provides good phosphorus to potassium ratio for flower production. This product also contains 20 different L-form amino acids, which are essential for building proteins, phenols, and alkaloids in addition to terpene production.

Additionally, Big Buds contains citric acid that helps marijuana plants transform sugars into energy, building big, thick buds throughout the canopy. Advanced Nutrients Big Bloom is one of the more popular bud hardening products in the cannabis nutrient market, boasting a 20% increase in yield with its use. The recommended dose is 1 tsp/gal or 5ml/litre.

KoolBloom by General Hydroponics

General Hydroponics offers KoolBloom bud hardener in two different formulations. The first, a liquid form with NPK ratios of 0 – 10 – 10, is recommended during the early stages of blooming. This recipe encourages the production of essential oils and fragrances while building a solid base for flower development.

The second formula is a dry concentrate bud hardener used in the last 1 – 2 weeks of flowering to stack the plant. Dry KoolBloom has NPK ratios of 2 – 45 – 28, which targets the bud hardening process. Both KoolBloom products contain the secondary nutrient, sulfur which aids in the activation of amino acids, proteins, and essential oils. Recommended dosing of the liquid varies through the flowering stage, whereas the dry concentrate is limited to ¼ tsp/gal.

Botanicare Hydroplex Bloom Enhancer 

Hydroplex Bloom Maximizer is another favourite bud hardener for seasoned marijuana growers. With a 0 – 10 – 6 NPK profile, Botanicare added amino acids, trace minerals, and vitamins to its’ Hydroplex recipe. This combination helps support plant development by encouraging enzymatic activity while elevating chlorophyll, oil, and sugar production.

The product promotes a healthy, strong flower structure encouraging thick, condensed cola formations. The PK boost helps marijuana plants overcome external stress while amplifying bud size and density. With a low dilution rate of 2 – 5 ml/gal, Hydroplex Bloom Maximizer is an economical option for hydro growers to save money while increasing bud thickness.

Hawaiian Bud by Grow More

Grow More’s Hawaiian Bud is a high phosphorus fertilizer designed to produce heavy bud-dense colas. With an NPK ratio of 5 – 50 – 17, Hawaiian Bud pushes energy transfer into flower and bud production. Accompanied by trace elements zinc, boron, copper, iron, manganese, and molybdenum, this urea-free formula promotes essential oil and resin production.

Additionally, humic acid and Norwegian kelp extract push bud development throughout the flowering stage resulting in solid, firm buds. Recommended doses range from ¼ – 1 tsp/gal beginning in the middle to late flowering phase depending on other nutrient inputs.

Post author
Charle Thibodeau
Charle’ Thibodeau is a freelance writer with almost a decade´s experience, specializing in cannabis content for the past two years. A strong motivation to educate, inform, and promote the culture surrounding this miraculous plant is her earnest mission.
See more from Charle Thibodeau

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