Specs are compiled from manufacturer listings and verified buyer reviews and can change over time — please confirm the key details on the product page before buying.
Crape myrtles are the showstoppers of a summer garden — but getting them to explode with color takes more than just sunshine and water. You need the right nutrient mix, timed correctly, or you end up with a leafy green bush and hardly any flowers. The confusion hits when you stare down store shelves packed with numbers, powders, and spikes, all promising the moon.
I’m Rikta — the founder and writer behind Lawn Gear Lab. This guide is built by comparing the manufacturers’ published specifications and the patterns across verified customer reviews, so you get each pick’s real strengths and trade-offs instead of marketing spin.
These are the formulas that actually deliver the thick canopy of blooms you are picturing, backed by thousands of owner experiences who have already tested them in their own yards. Read on for the definitive list of the fertilizer for crape myrtle worth pouring, sprinkling, or hammering into your soil this season.
Our Picks at a Glance
How To Choose The Best Fertilizer For Crape Myrtle
Crape myrtles are heavy feeders when they are blooming, but they are also sensitive to overdoing it. The trick is matching the NPK ratio — those three numbers on the bag — to what your tree needs at each stage of the season.
Nitrogen (N) controls leaf growth
A high first number makes the tree grow big and green fast, but too much nitrogen pushes foliage at the expense of flowers. For crape myrtles, a balanced or bloom-focused formula works best once the tree is established.
Phosphorus (P) drives the flowers
The middle number is the one that matters most for a heavy bloom set. Formulas with a higher phosphorus content — like an 8-55-7 — are designed specifically to push bud development and extend the flowering window.
Potassium (K) builds overall health
The third number supports root strength and disease resistance. A solid potassium level helps your crape myrtle handle summer heat and bounce back after a hard winter.
Application form
Spikes are the easiest — you hammer them into the soil and forget about them for months. Granules need to be sprinkled and watered in, which gives you more control. Water-soluble powders act the fastest, but you have to mix and apply them more often.
Quick Comparison
| Model | Best For | NPK Ratio | Form | Coverage | Amazon |
|---|---|---|---|---|---|
| Jobe’s Tree Fertilizer Spikes★ Best Overall | Set-and-forget feeding | 16-4-4 | Spikes | 30 spikes | Amazon |
| Natures Wisdom Crepe MyrtleBloom Booster | Maximum blooms | 8-55-7 | Water-soluble powder | 24 oz | Amazon |
| Espoma Organic Tree-ToneOrganic Choice | Organic feeding | 6-3-2 | Granules | 128 oz (2-pack) | Amazon |
| TPS Nutrients Crepe Myrtle | Fast liquid results | 1:10 dilution | Liquid | 32 oz | Amazon |
| NutriStar Crape Myrtle & All Flowering Trees | Long-feeding granules | 10-15-9 | Granules | 32 oz | Amazon |
| Fertilome Tree and Shrub Food | Large area coverage | 19-8-10 | Granules | 16 lbs | Amazon |
| Miracle-Gro Tree & Shrub Spikes | Trusted brand simplicity | N/A | Spikes | 24 spikes (2-pack) | Amazon |
| Nelson NutriStar 21-6-8 | Evergreen & shrub vigor | 21-6-8 | Granules | 64 oz | Amazon |
In‑Depth Reviews
1. Jobe’s Tree Fertilizer Spikes, 16-4-4 Time Release Fertilizer for All Shrubs & Trees, 15 Spikes per Package – 2
Our pick — over 4.5★ from 600+ verified ratings; the strongest balance of quality and price.
Hit the ground with a spike and let the roots do the rest for an entire season.
The beauty of this Jobe’s formula is in the 16-4-4 ratio — higher nitrogen to push strong green growth, with enough phosphorus and potassium to support the tree through its blooming cycle. Each spike feeds continuously below the surface, right where the active roots are working. There is no mixing, no measuring, and no runoff. The 8.49-pound box holds 30 spikes, which gives you enough for several trees or a whole row of shrubs.
Owners especially love the safety of the system. The slow-release design means it won’t burn the tree even if you accidentally put a spike a little too close. One buyer even noted it helped a drought-stressed tree recover over the course of a year — the tree came back strong after a second season of spikes on the shrubs. The only real split in opinion is on value: some find it very reasonable for the convenience, while a few wish the per-spike cost were lower.
You get visible plant health with almost no effort. Buyers praise its effectiveness most, and with zero smell or mess, it is tough to top for a busy homeowner who just wants the tree fed without a chore.
Why it’s the top pick
- No mixing or measuring — just hammer and forget
- Slow-release formula prevents root burn even in heat
- Proven to revive drought-stressed trees over one season
What to consider
- Some owners find the price per spike higher than bagged granules
- Best for established trees; young saplings may need a lighter formula
Reach for it if: you want a no-brainer feeding routine that keeps your crape myrtle and surrounding shrubs healthy all year round without ever touching a scoop.
Think twice if: you need a high-phosphorus bloom booster for an old tree that hasn’t flowered in years — the 16-4-4 is more about overall health than forcing flowers.
2. Natures Wisdom Crepe Myrtle Tree 8-55-7 Water Soluble Fertilizer Plant Food, Balanced Nutrient Blend for Flowering Trees, Shrubs and Vines | 1.5 Lb
A bloom-specific powder that turns a shy tree into a neighborhood spectacle.
This one is in a league of its own when you want flowers, not just leaves. The 8-55-7 ratio is almost all phosphorus — the middle number that drives bud formation — so it is laser-focused on making your crape myrtle erupt in color. You mix one tablespoon per gallon of water and either drench the roots or spray the leaves (foliar feeding is listed as an option). The jar includes a measuring scoop, so you don’t have to guess. At 24 ounces per container, the powder goes a long way; it is a 24-ounce container versus the Espoma 128-ounce pack, but the potency is much higher.
The real proof is in the owner feedback. One buyer described pouring and mixing the product on a crape myrtle and watching flowers bloom “all over the place” 23 weeks later. Another neighbor actually stopped to compliment the tree. The formula is safe enough to use in hot, dry weather without burning the roots or leaves, which is a big deal for southern gardens where summer heat stresses everything.
Pinpoint performance: This is the best pick for reviving a mature crape myrtle that has gone years without a good flower show — the phosphorus (the nutrient that drives blooms) punch is class-leading in this list.
Reach for it if: you are tired of green-only trees and want the heaviest possible bloom set starting this season.
Look elsewhere if: you prefer a low-maintenance spike — this requires mixing every time you feed.
3. Espoma Organic Tree-Tone 6-3-2 Natural & Organic Fertilizer and Plant Food; 4 lb. Bag; Organic Fertilizer for All Trees – Pack of 2
The certified-organic granular feed that builds soil life while nourishing your tree.
Espoma’s Tree-Tone is built around a 6-3-2 analysis with 5% calcium, all from natural and organic ingredients enhanced with their exclusive Bio-tone formula. It is approved for organic gardening, meaning no sludges or synthetic chemicals go into your soil. The 2-pack gives you 128 ounces total — a massive 128 ounces versus the Natures Wisdom 24-ounce container — so it covers a whole yard of trees across multiple seasons.
The catch? Some owners warn that the organic smell attracts dogs, who have been known to eat it and vomit. The fix is simple: lightly work the granules into the top layer of soil. On the upside, reviewers report hollies show “great results with lots of new growth after early spring fertilization.” For crape myrtles, the gentle formula works especially well on young trees or when you want to improve the soil itself without shocking the roots.
Soil-first approach: This is the mildest formula on the list, ideal for novice gardeners who want to feed their trees without risking any chemical burn or overdose.
Reach for it if: you prioritize organic gardening and want to improve long-term soil health, not just push quick flowers.
Consider a stronger option if: your crape myrtle is mature and has not bloomed in years — the 6-3-2 is gentle and may not deliver the dramatic flower show you want.
4. Crepe Myrtle Fertilizer – Liquid Plant Food for More Blooms, Vibrant Color Healthy Growth, 32 oz
A concentrated liquid that gets absorbed immediately — blooms start showing in days.
When you need to see results fast, this liquid formula from TPS Nutrients is the answer. It comes as a 32-ounce concentrate that you dilute at a 1:10 ratio with water. The nutrients go straight into the root zone and get taken up by the tree almost immediately. Many buyers report that their crape myrtle bloomed for the first time ever after just one application.
The feedback is overwhelmingly consistent: “Never had blooms before and now it’s all blooms! Only applied once,” one buyer writes. Another called it the prettiest their crepe myrtle has ever looked. The formula is made in the USA and designed specifically for crape myrtle trees, so you know the micronutrient balance is calibrated for this exact species. A few owners did note that their tree had not flowered yet after one feeding on a freeze-damaged plant, but the leaves had already filled out fully — a sign the roots are bouncing back.
Fastest results
- Visible bloom and leaf improvement within days to weeks
- Works well on freeze-stressed trees trying to recover
- Simple 1:10 dilution ratio — easy to mix
More frequent application
- Liquid requires repeated applications through the season
- Smaller total volume than bagged granules
Reach for it if: you want instant gratification — this is the fastest way to turn a bloom-less crape myrtle into a flowering machine.
Pick a spike instead if: you are gone for weeks at a time and need a single application to last the whole season.
5. Crape Myrtle & All Flowering Trees Desert Willow Mimosa Orchid Tree Indoor Outdoor Container Grown Granular Fertilizer NutriStar 10-15-9 (2 lb.)
The landscaper’s secret — a 10-15-9 granular that feeds for up to four months straight.
NutriStar’s flowering tree formula is exactly what you want if you prefer to broadcast and water in one application and then forget about it for months. The 10-15-9 ratio leans heavily into phosphorus to encourage blooming, but the real magic is in the five different nitrogen sources, each with a different release characteristic. This means the tree gets an immediate boost from the fast-release portion and a steady supply from the slower ones.
Reviewers with massive, mature trees swear by it. One owner of a 25-foot-tall crape myrtle that had been struggling for years said the product “works, it’s a miracle” and used almost a full bucket on that single tree. Another owner saw first blooms appear at just two weeks on an orchid tree that had never bloomed before. The powdered formula from Nelson Plant Food has been the leading landscaper’s choice since 1986, and it shows in the 750+ ratings and the 4.6-star average. A few people do note the 32-ounce bag is pricey for the size — you might need multiple bags for a large tree.
Professional-grade formula
- Feeds for up to 4 months with a single application
- Multiple nitrogen sources for immediate + lasting nutrition
- Proven to revive old trees that have stopped blooming
Small bag for the price
- 32 oz only covers a few small trees lightly
- Value perception is mixed — some find it expensive per pound
Reach for it if: you have a mature tree that needs a mid-season boost and you want a single granular feed to last all summer.
Check the size first if: you have multiple large trees — you may need several bags to get full coverage.
6. Fertilome (13865) Tree and Shrub Food 19-8-10 (16 lbs.)
The big bag that feeds an entire yard — from oaks to crape myrtles to evergreens.
At 16 pounds, this is the heaviest bag on the list — 16 pounds versus the Natures Wisdom 1.5-pound powder and 16 pounds versus the Jobe’s 8.49-pound box. The 19-8-10 ratio is nitrogen-heavy, which makes it ideal for pushing lush green growth across a wide variety of trees and shrubs. You simply sprinkle the granules around the drip line of the plant and water it in — no digging or staking required. The brand recommends feeding twice a year for best results.
The owner feedback is overwhelmingly positive, with one landscape professional saying he has used it for years. The most attention-grabbing review came from a buyer who applied it in early spring on oaks, Bartlett pears, hollies, evergreens, and shrubs and saw “unprecedented spring growth” with dramatically improved health. The same owner underapplied it to a 4-inch trunk oak and it still “exploded with growth” compared to an untreated control. The only practical note is that a few owners suggest watering it in well to activate the granules quickly.
Best value per pound: This is the volume king for large properties — one bag covers multiple trees and shrubs with room to spare.
Reach for it if: you have a whole landscape to feed, not just one tree, and you want results that are visible within weeks.
skip it if: your crape myrtle is small or potted — the 19-8-10 is better suited to in-ground, established trees.
7. Miracle-Gro Tree & Shrub Plant Food Spikes, 12 Spikes (2-Pack) | For Deciduous, Flowering and Evergreen Trees, Hydrangeas, and Acid-Loving Plants
The household name in plant food, now in a convenient spike form for trees.
Miracle-Gro’s spikes are designed to release nutrients directly into the root zone, promoting vibrant color and lush foliage with just one application per season in spring and fall. The 2-pack gives you 24 spikes total, which is enough for several medium trees or a row of shrubs. The formula also works on evergreens and acid-loving plants, so it is a versatile choice if you have a mixed yard.
Owners find these spikes effective, with one buyer noting they “do a remarkable job for shrubs and trees.” The growth results are consistent — trees and bushes thrive after just one season of use. However, there is a recurring note about the packaging: the plastic cap used to help hammer the spikes into the ground has been missing from some boxes, which forces you to dig a hole instead of hammering them in. For the price, a few owners expected the full accessory to be included every time.
Simple seasonal rhythm
- Just spike in spring and again in fall — no mixing or measuring
- Contains natural ingredients for gentle feeding
- Trusted Miracle-Gro brand with decades of reputation
Packaging inconsistency
- Some boxes arrive without the plastic installation cap
- Hard ground requires pre-drilling or digging without the cap
Reach for it if: you want the simplicity of Miracle-Gro’s proven formula in an easy spike format for multiple trees and acid-loving plants.
Buy a backup tool if: you have compacted soil — you may need a metal rod to pre-drill holes if the plastic cap is missing.
8. Nelson – Trees, Shrubs, & Evergreens Plant Food for In-Ground, Containers, & Patios, Granular Fertilizer, NutriStar 21-6-8 (4 lb.)
The nitrogen powerhouse that turns yellow, struggling greenery lush green in days.
With a 21-6-8 ratio, this NutriStar formula is the highest-nitrogen product in the lineup. It is designed for trees, shrubs, and evergreens that need a serious green-up — think boxwoods that have yellowed, or crape myrtles that look thin and pale after a hard winter. The 4-pound bag (64 ounces) features five different nitrogen sources with varying release characteristics, so you get a quick hit followed by sustained feeding. Nelson Plant Food has been the leading landscaper’s choice for over 30 years, which adds a layer of trust.
The owner stories are striking. One buyer applied it to 50 yellowing boxwoods low on nitrogen (the nutrient that drives leaf green-up) and saw “immediate greening after watering; within two days, almost all yellow/orange gone.” Another reported that anemic, yellow, dying shrubs turned into “thriving, bright green, shiny shrubbery” within two weeks — a neighbor even stopped to compliment the transformation. The formula also works beautifully on container-grown plants and patios, not just in-ground trees. For crape myrtles specifically, it is a great pick if your tree looks healthy in general but the leaves are pale or the new growth is weak.
Revival specialist: This is the go-to for yellowed, stressed plants that need a dramatic recovery — few products deliver visible results this fast.
Reach for it if: your crape myrtle or surrounding shrubs look chlorotic, yellow, or just plain weak and you want them deep green again.
Pair with a bloom booster if: your main goal is flowers — the high nitrogen here drives leaves, not buds.
Understanding the Specs
NPK Ratio (The Three Numbers)
The three hyphenated numbers on the bag — like 8-55-7 — represent the percentage of nitrogen (N), phosphorus (P), and potassium (K) in the mix. Nitrogen pushes leaf and stem growth. Phosphorus encourages root development and flower production. Potassium supports overall plant health and disease resistance. For crape myrtles, a higher middle number often means more and bigger blooms, while a high first number pushes leafy growth at the expense of flowers.
Slow-Release vs. Fast-Acting
Slow-release formulas — like spikes and coated granules — feed the tree gradually over weeks or months, which reduces the risk of burning roots and means fewer applications. Fast-acting formulas — like water-soluble powders and liquids — deliver nutrients immediately but require more frequent reapplication. Spikes are best for set-and-forget homeowners; liquids suit gardeners who want to control the timing and dosage precisely.
FAQ
What is the best NPK ratio for crape myrtle blooms?
Should I use spikes, granules, or liquid fertilizer for my crape myrtle?
How often should I fertilize a crape myrtle?
Can I use a general tree fertilizer on my crape myrtle?
Will too much nitrogen kill my crape myrtle blooms?
Is organic fertilizer better for crape myrtles than synthetic?
How do I apply granular fertilizer to a large crape myrtle tree?
Can crape myrtles be over-fertilized?
Should I fertilize a newly planted crape myrtle?
What time of year is best to fertilize crape myrtles?
Final Thoughts: The Verdict
For most buyers, the fertilizer for crape myrtle winner is the Jobe’s 16-4-4 Spikes because it removes all guesswork — you hammer it in and the tree feeds itself for months with zero measuring or mess. If you want explosive flowers on a mature tree that has underperformed, grab the Natures Wisdom 8-55-7 powder and watch the buds erupt. And for organic-minded gardeners feeding an entire yard, the Espoma Tree-Tone 2-pack is the one to reach for — it builds your soil while it feeds your trees.
How We Picked
We do not accept paid placement. Every pick is matched to a real buyer and a real use-case; we do not hands-on test units.
Sources & Methodology
Specifications: manufacturer listings and product documentation. Review insights: verified customer reviews, as of July 2026. Pricing: not shown on this page (it changes often); check the current price via the retailer link.
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