10 Best Fertilizers for Crepe Myrtle Trees to Boost Growth and Blooms

I’ve found that the best crepe myrtle fertilizers feature high phosphorus content, like the 8-55-7 Crepe Myrtle Plant Food, which dramatically boosts blooming frequency. Miracle-Gro Tree and Shrub Spikes offer convenient slow-release nutrition for busy gardeners, while NutriStar 10-15-9 Granular provides immediate feeding with sustained release. Complete Liquid Plant Food works exceptionally well for struggling trees in sandy soil conditions. These fertilizers consistently earn 4.6-star ratings and transform ordinary trees into spectacular flowering displays when you understand proper application techniques.

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Notable Insights

• Choose fertilizers with high phosphorus content (like 8-55-7 or 5-20-10 ratios) to promote abundant blooming in crepe myrtles.
• Liquid fertilizers provide rapid absorption and quick results, while slow-release spikes offer consistent nutrition for busy gardeners.
• Apply one gallon of fertilizer solution per foot of tree height during the growing season for optimal coverage.
• Maintain soil pH between 6.0-7.0 to ensure proper nutrient absorption and maximize fertilizer effectiveness for crepe myrtles.
• Consider micronutrients like iron, manganese, and zinc which are essential for leaf strength, photosynthesis, and healthy growth regulation.

Crepe Myrtle Plant Food 24oz 8-55-7

Carl Pool’s Crepe Myrtle Plant Food stands out as the top choice for gardeners seeking rapid, visible improvements in their trees’ blooming performance and overall health. This scientifically formulated 8-55-7 fertilizer delivers nutrients through both roots and leaves, ensuring thorough feeding that promotes optimum growth. You’ll appreciate the straightforward application process: simply mix one tablespoon per gallon of water and apply every 7-14 days during growing season. With over 2,300 customer ratings averaging 4.6 stars, this proven formula consistently delivers results that include increased blooming frequency, enhanced foliage development, and stronger overall tree health for crepe myrtles of all sizes.

Best For: Gardeners with crepe myrtle trees who want fast, visible improvements in blooming frequency and overall tree health through a scientifically formulated feeding program.

Pros:

• Dual feeding method through both roots and leaves ensures thorough nutrient absorption for optimal growth results
• High customer satisfaction with 4.6 out of 5 stars from over 2,300 ratings, demonstrating proven effectiveness
• Simple application process with clear mixing ratios and frequency guidelines for consistent feeding

Cons:

• Application can be challenging on taller crepe myrtle trees due to the need for thorough coverage
• Requires regular application every 7-14 days during growing season, which may be time-consuming for some gardeners
• Recommended amounts may seem impractical for very large trees, raising questions about cost-effectiveness

Crepe Myrtle Fertilizer, Complete Liquid Plant Food (8 oz)

This concentrated 8-ounce liquid fertilizer stands out as the top choice for gardeners who want maximum results from a specialized, easy-to-apply formula. You’ll appreciate how this complete plant food encourages vibrant blooms while strengthening branch development, delivering the nutrients your crepe myrtle needs for peak health. The liquid format guarantees quick absorption, making it particularly effective for revitalizing struggling trees that appear unhealthy or fail to bloom consistently. Users consistently report significant improvements, especially in challenging conditions like zone 9a sandy soil environments. You’ll find the included care instructions straightforward to follow, and the Made in USA quality gives you confidence in results.

Best For: Gardeners with crepe myrtle trees that need revitalization, especially those in challenging growing conditions like zone 9a with sandy soil who want a specialized, easy-to-apply liquid fertilizer.

Pros:

• Quick absorption liquid formula that encourages vibrant blooms and strengthens branch development
• Highly effective for revitalizing struggling or unhealthy trees with consistent user-reported improvements
• Made in USA with complete care instructions included for easy application

Cons:

• Small 8 oz size may require frequent repurchasing for multiple or large trees
• Specialized formula is only designed for crepe myrtle trees, limiting versatility
• Concentrated liquid format may require careful measuring to avoid over-application

NutriStar 10-15-9 Granular Fertilizer for Flowering Trees (2 lb.)

NutriStar 10-15-9 Granular Fertilizer stands out as an exceptional choice for gardeners who want to maximize their crepe myrtle’s blooming potential while supporting multiple flowering trees in their landscape. This versatile formula delivers targeted nutrition through its balanced NPK ratio, featuring higher phosphate content that specifically promotes abundant flower production. You’ll appreciate the five different nitrogen sources that provide both immediate feeding and sustained release, ensuring your trees receive consistent nutrition for up to four months. The granular format works perfectly for both in-ground plantings and container gardens, giving you flexibility in application methods. Essential micronutrients like iron, manganese, and zinc support overall tree health while optimizing bloom quality and quantity.

Best For: Gardeners who want to maximize blooming potential in crepe myrtles and other flowering trees while providing long-lasting nutrition for both in-ground and container plantings.

Pros:

• Five different nitrogen sources provide immediate feeding plus sustained release for up to 4 months
• Higher phosphate content (15%) specifically promotes increased bloom quantity, size, and quality
• Versatile application for multiple flowering tree varieties and works with both established and newly planted trees

Cons:

• 2 lb. package size may not be sufficient for large landscapes with multiple mature trees
• Granular format requires proper watering to activate and may not provide as quick results as liquid fertilizers
• Limited to flowering trees only, requiring separate fertilizers for other garden plants and lawn areas

Miracle-Gro Tree and Shrub Plant Food Spikes (12 Spikes)

Gardeners who prefer a set-and-forget approach will find Miracle-Gro Tree and Shrub Plant Food Spikes perfectly suited for their busy schedules. These convenient spikes deliver a 15-5-10 NPK ratio directly to your crepe myrtle’s root zone, promoting vibrant blooms and healthy foliage through slow-release technology. You’ll simply drive the spikes two inches below the soil surface around your tree’s drip line, spacing them at least three feet apart for ideal nutrient distribution. With twice-yearly applications in spring and fall, this fertilizer eliminates guesswork while preventing over-fertilization risks common with liquid alternatives. The 12-spike package provides sufficient nutrition for multiple seasons.

Best For: Busy gardeners who want a low-maintenance, set-and-forget fertilizing solution for their trees and shrubs without the risk of over-fertilization.

Pros:

• Slow-release technology provides consistent nutrition directly to root zone with only twice-yearly applications
• Easy installation process eliminates guesswork and prevents over-fertilization common with liquid fertilizers
• Versatile formula works effectively on multiple plant types including deciduous, evergreen, and acid-loving plants

Cons:

• Limited quantity of 12 spikes may not be sufficient for larger properties with multiple trees
• Plastic installation caps are prone to breaking during the driving process
• Mixed user experiences with ease of installation, particularly in harder soil conditions

Natures Wisdom Crepe Myrtle Tree Water Soluble Fertilizer (1.5 Lb)

Specially formulated with an 8-55-7 nutrient ratio, Natures Wisdom Crepe Myrtle Tree Water Soluble Fertilizer delivers exceptional results for gardeners seeking abundant blooms and vigorous growth. This balanced blend provides essential nutrients and minerals that optimize your crepe myrtle’s nutritional needs, promoting robust development and vibrant flowering displays. You’ll appreciate its versatility, as it works effectively on various flowering ornamentals including hydrangeas, bougainvillea, and plumeria. The easy application process guarantees safe use without burning roots or leaves, even during hot, dry conditions. Users consistently report visible improvements, with neighbors often admiring their flourishing plants after regular fertilizer applications.

Best For: Gardeners who want to promote abundant blooms and vigorous growth in crepe myrtles and other flowering ornamentals like hydrangeas, bougainvillea, and plumeria.

Pros:

• Specially formulated 8-55-7 nutrient ratio optimizes crepe myrtle nutritional needs for robust development and vibrant blooms
• Versatile application works effectively on various flowering trees, shrubs, and vines beyond just crepe myrtles
• Safe, easy application that won’t burn roots or leaves even in hot, dry conditions

Cons:

• Results may vary significantly based on specific growing conditions and climate zones like Texas
• Limited to 1.5 lb package size which may require frequent repurchasing for larger gardens
• Water soluble formula requires regular reapplication compared to slow-release fertilizers

BioAdvanced 12 Month Tree and Shrub Protect and Feed (4 lb Granules)

BioAdvanced 12 Month Tree and Shrub Protect and Feed offers busy gardeners a thorough solution that combines fertilization with pest control in one convenient application. You’ll appreciate the slow-release fertilizer formula that delivers essential nutrients throughout the growing season, promoting healthier foliage and more vibrant blooms on your crepe myrtles. The granular format eliminates messy spraying, making application straightforward for both established landscape trees and container plants. This dual-action product targets common pests like aphids, Japanese beetles, and leafminers that frequently damage crepe myrtle foliage, while simultaneously feeding your trees for ideal growth and flowering performance.

Best For: Busy gardeners who want a convenient, long-lasting solution that combines pest control and fertilization for their trees and shrubs in a single annual application.

Pros:

• Provides 12 months of protection and fertilization with just one application, saving time and effort
• Targets multiple common pests including Japanese beetles, emerald ash borers, and aphids while delivering slow-release nutrients
• Easy-to-use granular format requires no mixing or spraying, making application simple for both landscape and container plants

Cons:

• Higher upfront cost compared to separate fertilizer and pesticide products
• Limited to granular application method, which may not be suitable for all garden situations
• Contains pesticides that may affect beneficial insects and require careful handling and storage

Leaves and Soul Crepe Myrtle Professional Liquid Fertilizer (3-5-4 Nutrient Blend, 8 oz)

When you’re seeking a fertilizer that delivers professional-grade results with convenient liquid application, Leaves and Soul Crepe Myrtle Professional Liquid Fertilizer stands out as an excellent choice for dedicated plant enthusiasts. This specialized 3-5-4 nutrient blend concentrate targets crepe myrtles specifically, promoting vibrant blooms and robust foliage development through its carefully balanced formula. You’ll appreciate the rapid absorption capability, which guarantees quick nutrient uptake and immediate benefits for both growth and flowering performance. The eco-friendly formulation supports sustainable gardening practices while delivering professional-grade nutrition that enhances root development and flower production effectively.

Best For: Gardening enthusiasts and plant care professionals who want to maximize crepe myrtle blooming performance and overall plant health with a specialized, eco-friendly liquid fertilizer formula.

Pros:

• Specialized 3-5-4 nutrient blend formulated specifically for crepe myrtles to promote vibrant blooms and healthy foliage
• Rapid absorption liquid formula provides quick nutrient uptake and immediate growth benefits
• Professional-grade, eco-friendly formulation suitable for both indoor and outdoor flowering plants

Cons:

• Only comes in 8 oz size which may require frequent repurchasing for larger gardens or multiple plants
• Specialized formula is optimized for crepe myrtles and may not be ideal for other plant varieties
• Liquid concentrate requires proper dilution and application knowledge for optimal results

The Old Farmers Almanac Tree & Shrub Fertilizer Spikes (Box of 6 Spikes)

The Old Farmers Almanac Tree & Shrub Fertilizer Spikes offer an excellent solution for gardeners who prefer low-maintenance fertilizing methods that deliver consistent, long-term nutrition to their crepe myrtles. These six spikes per box provide a mess-free application process, as you simply hammer them into the soil around your tree’s drip line. The slow-release formula guarantees your crepe myrtle receives steady nutrients over extended periods, promoting healthier foliage and stronger growth patterns. Users report noticeable improvements in tree vigor, with some experiencing dramatic size increases in their specimens. However, the large spike design works best for mature crepe myrtles rather than younger plantings.

Best For: Gardeners with mature trees and shrubs who want a low-maintenance, mess-free fertilizing solution that provides slow-release nutrition over extended periods.

Pros:

• Easy, mess-free application – simply hammer into soil with no additional work required
• Slow-release formula provides consistent nutrition over time, promoting healthier foliage and stronger growth
• Users report significant improvements in tree vigor, with some experiencing dramatic size increases

Cons:

• Large spike design makes them less suitable for smaller plants or precise placement needs
• Some users found spike remnants in soil 1-2 years later, raising questions about complete nutrient release
• Mixed results reported, with some users not observing meaningful changes in certain plant varieties

Miracle-Gro Shake N Feed Plant Food for Flowering Trees and Shrubs (8 lbs)

Miracle-Gro Shake N Feed Plant Food stands out as an excellent choice for gardeners who want a convenient, long-lasting fertilizer that nourishes crepe myrtles with natural ingredients. This 8-pound formula combines kelp, earthworm castings, bone meal, and feather meal to create a nutrient-rich blend that promotes both vibrant foliage and abundant blooms. You’ll appreciate how this fertilizer feeds your trees for up to three months, reducing the frequency of applications while maintaining consistent nutrition. Simply apply the granules evenly around the soil within your tree’s branch spread, avoiding direct contact with the trunk, then lightly work it into the soil and water thoroughly to activate the feeding process.

Best For: Gardeners seeking a convenient, long-lasting fertilizer for acid-loving flowering trees and shrubs who prefer natural ingredient formulations and want to reduce application frequency while maintaining consistent plant nutrition.

Pros:

• Contains natural ingredients like kelp, earthworm castings, bone meal, and feather meal for improved plant health
• Provides up to 3 months of continuous nutrition, reducing the need for frequent reapplication
• Works for both in-ground and container plants, offering versatility for different gardening situations

Cons:

• Requires reapplication every 3 months, which may be more frequent than some slow-release alternatives
• Must avoid direct contact with trunk and foliage during application, requiring careful placement
• Specifically formulated for acid-loving plants, limiting its use for trees and shrubs that prefer neutral or alkaline soil

Southern Ag All Purpose Granular Fertilizer 10-10-10, 5 LB Size: 5 LB

Budget-conscious gardeners who want reliable nutrition for their crepe myrtles will find Southern Ag All Purpose Granular Fertilizer 10-10-10 delivers exceptional value without compromising plant health. This balanced formula provides equal parts nitrogen, phosphorus, and potassium, ensuring your trees receive extensive nutrition for vigorous growth and abundant blooms. You’ll appreciate how easily these granules blend into soil around your crepe myrtles, eliminating concerns about root burn or plant stress that can occur with harsh chemical fertilizers. The 5-pound bag covers multiple trees, making it perfect for homeowners with several crepe myrtles throughout their landscape, and customers consistently rate this product 4.6 out of 5 stars for its effectiveness across various flowering trees and shrubs.

Best For: Budget-conscious gardeners with multiple crepe myrtles or flowering trees who want a reliable, balanced fertilizer that’s easy to apply and won’t burn their plants.

Pros:

• Balanced 10-10-10 formula provides equal nutrition without risk of root burn or plant stress
• Easy-to-apply granules blend smoothly into soil and cover multiple trees per 5-pound bag
• Highly rated by customers (4.6/5 stars) and ranked #72 in garden fertilizers for proven effectiveness

Cons:

• Limited to 5-pound bag size which may not be cost-effective for large properties
• Warranty information not clearly specified and must be requested separately
• Primarily distributed in Southeast US, potentially limiting availability in other regions

Factors to Consider When Choosing Fertilizer for Crepe Myrtle

When selecting fertilizer for your crepe myrtle trees, I recommend assessing several key factors that directly impact your tree’s health and flowering performance. The NPK ratio, soil pH levels, and your preferred application method will determine which fertilizer works best for your specific growing conditions. Additionally, you’ll want to take into account the release rate of nutrients and your tree’s current size, as these factors influence both timing and quantity of fertilizer applications.

NPK Ratio Requirements

Understanding the proper NPK ratio forms the foundation of successful crepe myrtle fertilization, as these three essential nutrients directly impact your tree’s blooming potential and overall vigor. I recommend focusing on formulations with higher phosphorus levels, such as 5-20-10 or 8-55-7 ratios, which specifically promote robust flowering and strong root development. You’ll want to maintain moderate nitrogen levels since excessive amounts can encourage lush foliage growth at the expense of those beautiful blooms you’re after. Don’t overlook potassium’s importance, as it strengthens your tree’s stress resistance and supports overall health throughout growing seasons. I suggest choosing fertilizers specifically formulated for flowering trees, ensuring they meet crepe myrtles’ unique nutritional requirements for peak performance.

Soil Ph Levels

Beyond selecting the right NPK ratio, soil pH levels play a fundamental role in determining how effectively your crepe myrtle can absorb those carefully chosen nutrients. I recommend maintaining soil pH between 6.0 and 7.0, which creates the slightly acidic to neutral conditions where crepe myrtles thrive best. When pH strays outside this range, nutrient lockout occurs, preventing your tree from accessing essential minerals regardless of fertilizer quality.

I suggest conducting regular soil tests to monitor pH levels and identify potential issues before they affect growth and blooming. If your soil tests too acidic, apply lime to raise pH gradually. Conversely, if it’s too alkaline, incorporate sulfur to lower pH levels. These amendments guarantee your fertilizer investments translate into vigorous growth and abundant blooms.

Application Method Preferences

Three primary application methods exist for crepe myrtle fertilization, each offering distinct advantages that align with different gardening preferences and practical needs. Liquid fertilizers provide rapid nutrient absorption and faster visible results, though they require more frequent applications every seven to fourteen days. Granular options offer convenience for taller trees since you can simply scatter them around the base without reaching high branches. Fertilizer spikes present the easiest insertion method, delivering slow-release nutrients over several months while minimizing over-fertilization risks. I recommend considering your maintenance preferences when selecting methods; liquid feeds suit gardeners seeking immediate results and don’t mind regular applications, while spikes work perfectly for those preferring less frequent care routines with consistent nutrient delivery throughout the growing season.

Release Rate Options

Fertilizer release rates play a fundamental role in determining how effectively your crepe myrtle receives nourishment throughout its growing season. I recommend considering slow-release fertilizers for their steady nutrient delivery, which lasts several months to a full year, reducing your application frequency considerably. These formulations align perfectly with crepe myrtles’ natural growth cycles, providing consistent feeding during critical development periods. Fast-release options offer immediate nutrient availability, making them ideal for addressing specific deficiencies or boosting growth quickly, though they’ll require more frequent applications. Environmental factors like temperature, moisture levels, and soil conditions directly influence how quickly nutrients become available to your trees. Understanding these release patterns helps you match fertilizer timing to your crepe myrtle’s seasonal needs, ensuring maximum growth and abundant blooming.

Tree Size Considerations

Your crepe myrtle’s size directly determines both the quantity of fertilizer you’ll need and the application strategy that works best for ideal growth. I recommend applying one gallon of mixed fertilizer per foot of your tree’s height, which guarantees adequate nutrition without waste. Larger specimens require extended root zone coverage, since their feeder roots often spread well beyond the visible canopy line. You’ll need proper equipment, like extension sprayers or telescoping tools, to reach upper foliage areas where foliar feeding occurs most effectively. Adjust your feeding schedule based on size too, with larger trees benefiting from intervals of 10-14 days rather than weekly applications, allowing sufficient time for complete nutrient absorption throughout their extensive root systems.

Seasonal Timing Needs

Timing your crepe myrtle fertilization correctly makes the difference between mediocre blooms and spectacular flowering displays that last throughout the growing season. I recommend applying fertilizer in early spring when new growth emerges, providing essential nutrients for robust flowering throughout summer. A second mid-summer application sustains continued nutrition during peak blooming periods, ensuring your trees maintain their vibrant displays. I strongly advise avoiding late fall fertilization, which encourages tender growth susceptible to frost damage that can weaken your trees. Before fertilizing, I suggest conducting soil tests to determine specific nutrient needs, allowing you to customize timing and formulation. Always water thoroughly after applying fertilizer, ensuring nutrients reach the root zone effectively during active growing periods.

Budget and Quantity

Smart financial planning guarantees you’ll maintain healthy, blooming crepe myrtles without straining your gardening budget throughout multiple growing seasons. I recommend calculating your fertilizer needs based on tree height, using the standard guideline of one gallon diluted fertilizer per foot of height. Compare cost per application rather than initial purchase price, since some products require monthly feeding while others last several months. Consider package sizes carefully; an 8-ounce liquid concentrate might seem cheaper initially, but a 2-pound granular fertilizer often provides better long-term value. I focus on nutrient concentration when evaluating costs, as higher-concentration formulas typically require smaller amounts per application, reducing your overall expenses while delivering superior results for your crepe myrtles.

Additional Nutrient Content

The extensive nutrient profile of your chosen fertilizer determines how effectively your crepe myrtles will develop strong root systems, produce abundant blooms, and maintain vibrant foliage throughout the growing season. Beyond the essential NPK ratio, I recommend seeking fertilizers that include vital micronutrients like iron, manganese, and zinc, which prevent yellowing leaves and support overall plant health. Potassium content deserves special attention because it strengthens your trees’ cold hardiness and disease resistance, making them more resilient during challenging weather conditions. Look for products containing soluble potash, which provides readily available potassium for immediate uptake. A complete nutrient profile guarantees your crepe myrtles receive thorough nutrition rather than just basic macronutrients, resulting in stronger growth and more spectacular blooming displays.

On a final note

I’ve walked you through eight excellent fertilizers that’ll transform your crepe myrtle’s growth and flowering potential. Whether you prefer liquid formulations, granular options, or convenient spikes, each product offers unique benefits for your specific gardening needs. Remember to evaluate your soil’s current nutrient levels, your tree’s maturity, and your maintenance preferences when making your selection. With proper fertilization and timing, you’ll enjoy spectacular blooms and vigorous growth throughout the growing season.