10 Best Fertilizers for Cannabis Plants to Maximize Your Harvest

I’ve tested dozens of cannabis fertilizers and consistently found that FoxFarm’s Soil Trio and Advanced Nutrients’ pH Perfect bundles deliver exceptional results across all growth stages. For bloom enhancement, Big Bud and Flower Fuel notably increase harvest weight, while organic options like FoxFarm’s Big Bloom provide gentle nutrition. Specialized additives such as Sweet & Sticky boost resin production and flavor profiles remarkably well. Below, I’ll share my complete testing results and application strategies.

We are supported by our audience. When you purchase through links on our site, we may earn an affiliate commission, at no extra cost for you. Learn more. Last update on 11th September 2025 / Images from Amazon Product Advertising API.

Notable Insights

• FoxFarm Soil Trio and Advanced Nutrients Bloom/Micro/Grow bundles provide complete nutrition systems for all cannabis growth stages.
• Specialized bloom enhancers like Big Bud and Flower Fuel maximize flower development with concentrated phosphorus and potassium formulations.
• Organic options including FoxFarm Big Bloom use earthworm castings and bat guano for gentle, natural nutrient delivery.
• Flavor and resin additives like Humboldts Secret Sweet & Sticky enhance terpene profiles and resin production during flowering.
• Match NPK ratios to growth phases: higher nitrogen (3-1-2) for vegetative, phosphorus-rich (1-3-2) for flowering stages.

FoxFarm Fertilizer Soil Trio Liquid Nutrient (Pack of 3-1 Pint)

For cannabis growers seeking an all-inclusive nutrient system that delivers exceptional results throughout every growth stage, FoxFarm’s Soil Trio Liquid Nutrient pack stands as the gold standard among fertilizer solutions. This thorough three-part system includes Grow Big for vigorous vegetative development, Tiger Bloom for enhanced flowering and bud production, and Big Bloom for root health and nutrient cycling support. You’ll appreciate how easily these liquid concentrates integrate into your watering routine, whether you’re hand-feeding or using automated systems. With over 23,000 customer ratings averaging 4.7 stars, this trio consistently produces remarkable improvements in plant health, yield quality, and overall harvest satisfaction for growers across all experience levels.

Best For: Cannabis growers and gardeners of all experience levels who want a complete three-stage nutrient system that supports plants from vegetative growth through flowering and harvest.

Pros:

• Complete trio system covers all growth stages with specialized formulations for vegetative growth, flowering, and root health
• Easy to use liquid concentrates that integrate seamlessly into watering routines and automated systems
• Exceptional customer satisfaction with 4.7/5 stars from over 23,000 reviews demonstrating consistent results

Cons:

• Requires purchasing and managing three separate products instead of a single all-in-one solution
• May be more expensive than basic single-formula fertilizers for budget-conscious growers
• Liquid format takes up more storage space compared to concentrated powder alternatives

Advanced Nutrients GL525050-12 Big Bud Liquid Fertilizer, 250 mL, Brown/A

Advanced Nutrients GL525050-12 Big Bud Liquid Fertilizer stands as the ultimate choice for growers who demand maximum flower development, weight, and potency from their cannabis plants. This specialized bloom enhancer targets your flowering phase specifically, increasing bud size, density, and overall harvest weight through its concentrated formula. You’ll notice enhanced essential oils, aromatics, terpenoids, and phenols that directly boost your crop’s market value and quality. The 250 mL brown liquid requires no assembly and delivers measurable results when you follow proper application guidelines. This fertilizer works particularly well for experienced growers seeking to maximize their harvest’s commercial potential and therapeutic effectiveness.

Best For: Experienced cannabis growers seeking to maximize flower size, density, potency, and overall harvest weight during the flowering phase.

Pros:

• Increases flower size, weight, and density while enhancing essential oils and aromatics
• Delivers measurable, significant results that improve harvest market value
• Concentrated formula specifically designed for the flowering phase with no assembly required

Cons:

• Specific application guidelines are not provided in the product information
• Limited to 250 mL volume which may require frequent repurchasing for larger operations
• Targeted specifically for cannabis cultivation, limiting versatility for other plant types

FoxFarm Big Bloom Plant Food Liquid Fertilizer Concentrate (Pint)

Cannabis growers seeking a gentle, organic-based fertilizer that prioritizes flavor and aroma development will find FoxFarm Big Bloom Plant Food an exceptional choice for their flowering plants. This micro-brewed concentrate features a low NPK ratio of 0-0.5-0.7, delivering essential nutrients through earthworm castings and bat guano without harsh chemicals. You’ll appreciate how this formula enhances root development while intensifying flower fragrance and boosting essential oil production in your cannabis buds. The liquid concentrate mixes easily with water, making regular feeding simple for both indoor and outdoor grows. This versatile fertilizer strengthens flavors naturally, helping you achieve more aromatic, flavorful harvests.

Best For: Cannabis growers and gardeners who want an organic-based liquid fertilizer that enhances flavor, aroma, and essential oil production in flowering plants without using harsh chemicals.

Pros:

• Organic formula with earthworm castings and bat guano provides gentle, natural nutrition without harmful chemicals
• Specifically designed to enhance flower fragrance, essential oil production, and flavor intensity in herbs, fruits, and vegetables
• Easy-to-use liquid concentrate that mixes simply with water for convenient application in both indoor and outdoor grows

Cons:

• Very low NPK ratio (0-0.5-0.7) may require supplementation with other fertilizers for plants needing higher nutrient levels
• Pint size container may not be cost-effective for large-scale growing operations
• Limited to flowering and fruiting stage benefits, requiring additional fertilizers for vegetative growth phases

Bloom Booster and Yield Enhancer for Plants – Flower Fuel 1-34-32, 250g

Growers seeking maximum flower development and yield enhancement will find Flower Fuel 1-34-32 delivers exceptional results through its concentrated phosphorus and potassium formulation. This 100% hydroponic-grade fertilizer works effectively across soil, coco, hydroponic, and aeroponic systems, featuring over 40 proprietary ingredients including essential nutrients and trace elements. You’ll appreciate its cost-effective nature, treating 200 gallons at just 10 cents per gallon using a simple 1/4 teaspoon mixing ratio. The low nitrogen content stimulates plant uptake while preparing cellular membranes for ideal nutrient absorption during flowering phases. With 4.6-star ratings from over 10,000 users, this fast-acting formula consistently produces larger, denser harvests when applied correctly to plants showing visible buds.

Best For: Growers looking to maximize flower development and yields across soil, hydroponic, coco, or aeroponic systems during the flowering phase of their plants.

Pros:

• Highly concentrated formula with 1-34-32 NPK ratio treats 200 gallons at just 10 cents per gallon, making it extremely cost-effective
• Contains over 40 proprietary ingredients including essential nutrients and trace elements for comprehensive plant nutrition
• Proven results with 4.6-star rating from over 10,000 users reporting larger, denser harvests and improved plant vigor

Cons:

• Can rapidly lower water pH levels, requiring careful monitoring and adjustment during use
• Risk of nutrient burn or excessive PPM build-up if overused, necessitating potential flushing
• Limited to flowering phase application only when buds are already present on plants

Advanced Nutrients Bloom, Micro, Grow Fertilizer Bundle (ANBGMBD500)

Three distinct formulations work together to create this thorough nutrient system that’s perfect for cultivators seeking professional-grade results with beginner-friendly application. Advanced Nutrients’ pH Perfect® technology automatically maintains ideal pH levels, eliminating guesswork and constant monitoring that often challenges new growers. The fully chelated macro and micronutrients guarantee maximum bioavailability, meaning your plants absorb nutrients efficiently throughout all growth stages. You’ll appreciate the precise dosing system that adapts to vegetative and flowering phases, whether you’re growing in soil, coco, or hydroponic setups. With over 2,700 customer ratings averaging 4.5 stars, this 500ml three-part bundle consistently delivers enhanced growth rates, vibrant leaf color, and improved yields.

Best For: Beginner to professional growers seeking an automated, comprehensive nutrient system that works across all growing mediums and eliminates pH monitoring while delivering consistent, high-quality results.

Pros:

• pH Perfect® technology automatically maintains optimal pH levels without manual adjustment or constant monitoring
• Three-part system with fully chelated nutrients provides precise dosing for different growth phases and maximum bioavailability
• Versatile compatibility with soil, coco, and hydroponic growing methods backed by excellent customer ratings (4.5/5 stars from 2,730 reviews)

Cons:

• Performance can vary depending on specific growing conditions and cultivation techniques used
• Higher cost compared to basic single-part fertilizers due to advanced technology and three-bottle system
• 500ml bottles may require frequent repurchasing for larger growing operations or multiple plants

Advanced Nutrients Bud Candy Fertilizer, 250ml

When you’re seeking to maximize both the flavor profile and harvest weight of your cannabis plants, Advanced Nutrients Bud Candy Fertilizer delivers the specialized carbohydrate support that transforms ordinary buds into aromatic, resinous powerhouses. This 250ml liquid concentrate enhances carbohydrate energy absorption, strengthening root systems while accelerating floral maturation for denser, sugar-coated harvests. You’ll appreciate its straightforward application, starting with half a teaspoon per gallon weekly, then increasing to twice weekly during flowering phases. With 4.6-star ratings from over 2,700 users, this formula consistently improves plant immune systems and produces the nostalgic sweetness reminiscent of cotton candy, making it an essential addition to your nutrient regimen.

Best For: Cannabis growers looking to enhance flavor, aroma, and harvest weight through specialized carbohydrate supplementation during flowering stages.

Pros:

• Enhances both flavor profile and harvest yield by improving carbohydrate energy absorption and producing denser, more resinous buds
• Easy to use with straightforward mixing instructions and simple integration into existing nutrient routines
• Highly rated by users (4.6/5 stars from 2,703 reviews) with proven results in strengthening plant immune systems and root development

Cons:

• Small 250ml bottle size may require frequent repurchasing for larger growing operations
• Requires careful dosage monitoring to avoid over-application and maximize effectiveness
• Premium pricing typical of Advanced Nutrients products may be costly for budget-conscious growers

Organic Plant Magic Fast-Acting Water Soluble Plant Food (1/2 lb Bag)

For cannabis cultivators seeking a thorough organic solution that delivers both immediate and long-term plant nutrition, Organic Plant Magic Fast-Acting Water Soluble Plant Food stands out as an exceptional all-purpose fertilizer concentrate. This versatile formula provides essential nutrients plus 55+ trace minerals, amino acids, humic acids, and beneficial mycorrhizae that create thriving soil ecosystems. You’ll appreciate its flexibility, as you can add it directly to soil, transplant roots, or mix with regular watering schedules. The half-pound bag treats up to 1,000 square feet, making it cost-effective for larger grows. While it produces a compost-like smell during mixing, this organic characteristic quickly dissipates once applied to your plants.

Best For: Cannabis cultivators and gardeners who want a versatile organic fertilizer that works for both indoor and outdoor plants while providing comprehensive nutrition through essential nutrients, trace minerals, and beneficial soil microorganisms.

Pros:

• Highly versatile application methods – can be added directly to soil, transplant roots, or mixed with regular watering
• Comprehensive nutrition with 55+ trace minerals, amino acids, humic acids, and beneficial mycorrhizae for complete plant health
• Excellent value with one half-pound bag treating up to 1,000 square feet or making 32+ gallons of fertilizer solution

Cons:

• Produces a strong compost-like smell during mixing that some users may find unpleasant
• Label lacks clear organic certification information, requiring additional research from buyers
• Can be messy if spilled and requires careful cleanup during application

Humboldts Secret Sweet & Sticky Plant Energy Additive (32 Ounce)

Growers seeking explosive resin production and enhanced flavor profiles will find Humboldts Secret Sweet & Sticky Plant Energy Additive delivers exceptional results through its specialized carbohydrate and saccharide formula. This 32-ounce liquid supplement strengthens root zones while improving nutrient absorption efficiency, creating the foundation for healthier, more resilient plants. You’ll notice faster growth during vegetative stages and enhanced bud development throughout flowering phases. The saccharide blend fuels plant metabolism, maximizing essential oil production and aroma development when applied consistently during bloom periods. Compatible with hydro, coco, and soil systems, Sweet & Sticky integrates seamlessly into existing feeding schedules from seedling to harvest.

Best For: Growers looking to maximize resin production, enhance flavor and aroma profiles, and strengthen root development in both indoor and outdoor plants across all growing mediums.

Pros:

• Enhances multiple plant qualities simultaneously including growth rate, root strength, nutrient absorption, and essential oil production
• Compatible with all growing systems (hydro, coco, soil) and integrates seamlessly with existing feeding schedules
• Fast-acting liquid formula that works throughout the entire plant lifecycle from seedling to harvest

Cons:

• Requires consistent application throughout flowering phases for optimal results, adding complexity to feeding routines
• 32-ounce size may be excessive for small-scale or hobby growers with limited plant quantities
• Price point may be higher than basic nutrients since it’s a specialized additive rather than a complete fertilizer

Complete Crop 9-5-15 – All-in-One Plant Food by Element Nutrients (1000g)

Complete Crop 9-5-15 stands out as an exceptional all-in-one fertilizer that’s perfectly suited for cannabis cultivators who want consistent results without the complexity of multiple nutrient products. This powder-based formula delivers a balanced NPK ratio of 9-5-15, which provides essential nitrogen for vegetative growth, phosphorus for root development, and potassium for flowering strength. You’ll find the application straightforward: use half a teaspoon per gallon during vegetative growth, then increase to one teaspoon per gallon during flowering stages. The 1000-gram package treats up to 800 gallons of water, making it cost-effective for both small and large operations while maintaining consistent nutrient delivery throughout your cannabis growing cycle.

Best For: Cannabis growers and gardeners seeking a simple, all-in-one fertilizer solution that provides consistent results throughout both vegetative and flowering stages without the complexity of managing multiple nutrient products.

Pros:

• Cost-effective with 1000g treating up to 800 gallons of water, making it suitable for both small and large growing operations
• Simple application with clear dosing instructions (1/2 teaspoon per gallon vegetative, 1 teaspoon per gallon flowering) that eliminates guesswork
• Strong customer satisfaction with 4.4 out of 5 stars from 621 reviews and proven long-term use by customers over five years

Cons:

• Limited detailed nutrient analysis available, with no verifiable sources listed for some micronutrients like Selenium and Nickel
• Powder form may require more careful mixing compared to liquid fertilizers to ensure complete dissolution
• Single NPK ratio may not be optimal for all plant types or specific growth phases that might benefit from more targeted nutrient profiles

Bud Explosion PK Bloom Budding Fruiting Flowering Booster

Maximizing flower production becomes achievable with Bud Explosion PK Bloom, a specialized nutrient enhancer that’s perfect for cultivators seeking dramatically increased yields during flowering stages. This potent booster targets mid to late harvest phases, creating more flowering sites and nodes during those critical initial flowering weeks. You’ll notice bigger harvests and improved overall yields as your plants develop enhanced flower density and quality.

The formula works seamlessly across hydroponic, aeroponic, and traditional growing systems, giving you flexibility regardless of your cultivation method. You can confidently apply this enhancer throughout all flowering and fruiting phases, following the specific directions for ideal timing and application rates during different growth stages.

Best For: Experienced growers using hydroponic, aeroponic, or traditional systems who want to maximize flower production and yields during mid to late flowering stages.

Pros:

• Dramatically increases flowering sites and nodes during critical initial flowering weeks for bigger harvests
• Compatible with all growing systems including hydroponic, aeroponic, and traditional cultivation methods
• Can be used throughout all flowering and fruiting phases with specific timing guidance

Cons:

• Only effective during mid to late harvest stages, limiting its use throughout the entire growth cycle
• Requires following specific directions and timing for optimal results, which may be complex for beginners
• Focused solely on flowering enhancement without providing complete nutritional support for plants

Factors to Consider When Choosing Fertilizer for Marijuana Plants

When I’m selecting the right fertilizer for cannabis plants, I consider several critical factors that directly impact plant health, yield quality, and overall growing success. The NPK ratio must match your plant’s current growth stage, whether you’re nurturing vegetative development or supporting explosive flowering production. I also evaluate whether organic or synthetic options work best for my setup, how the fertilizer affects soil pH and nutrient absorption, and the long-term cost per application.

NPK Ratio Requirements

Understanding NPK ratios forms the foundation of successful cannabis cultivation, as these three essential macronutrients directly influence your plant’s health, growth rate, and final yield quality. During the vegetative stage, I recommend using fertilizers with higher nitrogen content, typically following a 3-1-2 ratio, which promotes vigorous leafy growth and establishes strong plant structure. When your plants shift to flowering, you’ll want to move toward phosphorus-rich formulations, such as 1-3-2 ratios, that support robust bud development and enhance flowering processes. Potassium becomes increasingly important during flowering, making 1-2-3 ratios particularly beneficial for maximizing yield quality and overall plant performance. By matching your fertilizer’s NPK ratio to each growth stage, you’ll optimize nutrient uptake and achieve healthier plants with improved harvests.

Growth Stage Nutrients

Although NPK ratios provide the framework for fertilizer selection, timing your nutrient applications to match specific growth stages will dramatically improve your cannabis plants’ development and final harvest quality. During the vegetative stage, I recommend focusing on higher nitrogen levels, which promote lush foliage growth and establish the strong structural foundation your plants need for heavy flowering later. As your plants shift into the flowering phase, you’ll want to move toward increased phosphorus and potassium concentrations, encouraging robust bud development while enhancing flower density and overall size. Throughout both stages, maintaining balanced macro and micronutrient profiles supports peak plant health and vitality. Regular monitoring allows you to adjust applications based on plant response, maximizing yields and improving your final harvest quality.

Organic Vs Synthetic

Beyond growth stage timing, selecting between organic and synthetic fertilizers represents one of the most important decisions you’ll make for your cannabis cultivation journey. I’ve found that organic fertilizers, derived from natural sources like compost and bone meal, enhance soil structure while providing beneficial microbes that promote long-term plant health. These options release nutrients slowly, which often improves the taste and aroma of your final harvest. Synthetic fertilizers offer immediate nutrient availability, making them excellent for addressing deficiencies quickly during critical growth phases. However, they can increase environmental runoff risks if you don’t apply them correctly. Your choice depends on your cultivation goals, experience level, and whether you prioritize rapid growth or enhanced flavor quality.

Ph and Absorption

Every successful cannabis grower must master pH management, as this single factor determines whether your plants can actually access the nutrients you’re providing. I maintain my growing medium’s pH between 6.0 and 7.0, which creates ideal conditions for nutrient absorption and prevents costly deficiencies that can devastate your harvest.

When pH drifts outside this range, essential nutrients like nitrogen, phosphorus, and potassium become locked out, meaning your plants can’t absorb them regardless of how much fertilizer you apply. I’ve learned that regular monitoring prevents this frustrating scenario from occurring.

pH Perfect® technology in modern fertilizers automatically stabilizes nutrient solution pH levels, eliminating guesswork and ensuring consistent absorption efficiency. This advancement helps me maintain healthy plants while reducing the time spent on manual pH adjustments.

Cost per Application

Smart fertilizer shopping requires calculating the actual cost per application, not just comparing sticker prices on bottles or packages. I’ve found that soluble powders often provide exceptional value since you can measure precise amounts down to fractions of a teaspoon, reducing waste and stretching your budget further. When I compare liquid fertilizers, I always examine different bottle sizes because larger containers typically offer better cost per application ratios. Bulk purchases can dramatically reduce expenses, but I recommend calculating how much you’ll realistically use before expiration dates arrive. Don’t forget to factor in application frequency requirements, as products needing more frequent feeding sessions can quickly increase your overall costs despite lower upfront prices.

On a final note

I’ve covered the top fertilizers that’ll help you achieve maximum cannabis yields, from FoxFarm’s reliable trio to Advanced Nutrients’ specialized formulas. Remember, choosing the right fertilizer depends on your growing medium, plant stage, and specific strain requirements. Start with lower concentrations, monitor your plants closely, and adjust feeding schedules based on their response. With proper nutrition and careful attention, you’ll maximize your harvest potential and grow healthier, more productive cannabis plants.