Guaranteed Analysis
Nutrient Breakdown
N · Nitrogen4%
Provides 4% total nitrogen (1.5% water soluble, 2.5% water insoluble) for steady vegetative growth and leaf expansion that powers fruit production without burning shallow blueberry roots.
P · Phosphorus6%
Delivers 6% available phosphate (P2O5) to promote strong root establishment, increased flower bud formation, and heavier fruit set in blueberry bushes.
K · Potassium4%
Supplies 4% soluble potash (K2O) to improve fruit quality, winter hardiness, and disease resistance — critical for perennial blueberry plantings.
Derived from: Total Nitrogen (N) 4.0% (1.5% Water Soluble Nitrogen, 2.5% Water Insoluble Nitrogen), Available Phosphate (P2O5) 6.0%, Soluble Potash (K2O) 4.0%. Derived from: Elemental Sulfur, Animal Protein Meals, Vegetable Protein Meals, Natural Sulfate of Potash, Natural Nitrate of Soda, Bone Char
Overview
What It Is
Organic Blueberry Fertilizer 4-6-4 is a crop-specific organic fertilizer formulated for the unique nutritional and pH requirements of blueberry bushes and similar acid-loving plants. Blueberries need specific nutrients — iron, manganese, and sulfur — that become more available in acidic soils (pH 4.5-5.5). Soils high in calcium, magnesium, or sodium can inhibit blueberry growth, causing chlorosis (yellowing leaves), stunted growth, and poor fruiting.
This fertilizer addresses both nutrition and pH management simultaneously. The elemental sulfur component actively lowers soil pH over time, while the organic protein meals and bone char provide a slow, steady release of macro and micronutrients that match the blueberry's moderate feeding requirements. The organic matter in the ingredients also improves soil structure, moisture retention, and beneficial microbial activity — all critical for the shallow, fibrous root system blueberries depend on.
Crop Fit
Best For
BlueberriesRaspberriesHuckleberriesAzaleasRhododendronsHydrangeasGardeniasCranberries
While formulated specifically for blueberries, this fertilizer works across all acid-loving plants that share similar pH and nutrient requirements. Blueberries (highbush, lowbush, and rabbiteye varieties) are the primary target — the gentle organic nutrition protects their sensitive shallow roots while the sulfur maintains the low pH they demand. Raspberries and huckleberries share similar acid-soil preferences and respond well to this formula. Ornamental acid-loving plants including azaleas, rhododendrons, hydrangeas, gardenias, heaths, heathers, mountain laurels, ferns, and lupine all thrive with the same 4-6-4 organic nutrition profile.
Application Rates
How Much to Use
| Garden & beds | 1 lb per 2 ft of crown diameter |
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| Lawn | N/A — formulated for blueberries and acid-loving plants, not turf |
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| Trees & shrubs | 1 lb per 2 ft of crown diameter, broadcast under the drip line |
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| Containers | 1 tbsp per gallon of soil |
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| Frequency | Twice per year — fall (after harvest) and spring (before bloom). If once, choose fall. |
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Step by Step
How to Apply
1Application Rate
Apply 1 lb of fertilizer per two feet of crown diameter beneath the plant's dripline.
2Root Zone Coverage
Spread evenly across the entire feeder root zone — blueberry roots are shallow and extend well beyond the branch tips.
3Fall Application
Apply in fall to build winter hardiness and store nutrients for spring. Fall is the most critical application timing.
4Spring Application
Apply again in spring to support shoot growth, leaf expansion, and flower bud formation.
5Mulch Tip
For faster response, temporarily remove mulch, apply fertilizer directly to soil, then replace mulch.
6Water In
Water lightly after application to begin organic nutrient activation without washing away material.
7Single Application
If limited to one application per year, choose fall for best long-term results and winter root development.
Blueberry feeder roots are shallow and extend well beyond the visible canopy, so broadcast fertilizer across this entire root zone. Fall applications are especially important — blueberry roots remain active well into fall, efficiently absorbing nutrients that build winter hardiness and provide stored nutrition for the critical spring growth flush. Spring applications further boost early-season vigor, flower bud development, and fruit production. While fertilizer can be applied over mulch (which blueberries should always have), temporarily removing mulch before application delivers faster nutrient uptake.
Handling & Timing
Safety & Season
Safety & Storage
Store in a cool, dry place in original packaging. Natural organic fertilizer — safe for use around children and pets when applied as directed. Wash hands after handling. May attract animals due to protein meal content — keep sealed between uses.
Seasonal Notes
Fall is the preferred and most important application window — apply after harvest to build winter hardiness and store nutrients for next spring's growth. Spring application supports the critical flush of new shoots, leaves, and flower buds that determine the season's fruit yield. Both applications together produce the best results. Avoid summer application during fruit ripening. Not applied in winter when ground is frozen.
In Context
How It Compares
Compared to the Wicked Organics Organic Evergreen Fertilizer, this product shares the same 4-6-4 NPK and ingredient base but is marketed and positioned specifically for blueberry growers with crop-specific application guidance. Versus synthetic blueberry fertilizers (like ammonium sulfate), this organic formula provides gentler, sustained feeding that won't damage blueberry's shallow, sensitive root system. Compared to cottonseed meal or sulfur-only amendments, the complete 4-6-4 formula provides balanced P and K nutrition that single-ingredient approaches lack.
Answers
Frequently Asked Questions
What is the best organic fertilizer for blueberries?
The best organic blueberry fertilizer provides balanced nutrition from natural, slow-release ingredients while supporting the acidic soil conditions blueberries require. An organic formula made from elemental sulfur, protein meals, bone char, and natural sulfate of potash delivers steady NPK nutrition and helps maintain low soil pH through the sulfur component. Organic fertilizers also build soil biology, which improves nutrient cycling in the root zone. Old Cobblers Farm™ Wicked Organics Organic Blueberry Fertilizer is specifically formulated for organic blueberry production with natural ingredients that support both plant and soil health.
How do I fertilize blueberries organically?
Apply organic blueberry fertilizer in early spring when new growth begins and optionally again after harvest in mid-summer. Spread 1–2 cups per established bush around the drip line, lightly incorporate into the top inch of mulch or soil, and water thoroughly. For young bushes, use ½–1 cup. Organic fertilizers release nutrients slowly, so apply 2–4 weeks before you want peak nutrition to give soil microbes time to process the ingredients. Old Cobblers Farm™ Wicked Organics Organic Blueberry Fertilizer provides gentle, season-long feeding from natural ingredients.
Does organic blueberry fertilizer acidify soil?
Organic blueberry fertilizers that contain elemental sulfur help maintain and lower soil pH over time. Soil bacteria convert elemental sulfur into sulfuric acid, which gradually acidifies the root zone — exactly what blueberries need. This natural acidification process is slower and more gentle than applying synthetic acids, providing a sustained pH-lowering effect. Regular application of sulfur-containing organic fertilizer helps keep soil in the 4.5–5.5 pH range blueberries require. Old Cobblers Farm™ Wicked Organics Organic Blueberry Fertilizer includes elemental sulfur for natural soil acidification.
What ingredients are in organic blueberry fertilizer?
Wicked Organics Organic Blueberry Fertilizer is formulated from elemental sulfur, vegetable protein meals, animal protein meals, natural sulfate of potash, nitrate of soda, and bone char. Elemental sulfur acidifies soil naturally. Protein meals provide slow-release nitrogen. Bone char contributes phosphorus and calcium. Sulfate of potash delivers chloride-free potassium essential for berry quality. All ingredients are OMRI-Listed for certified organic use. Old Cobblers Farm™ Wicked Organics uses only high-quality natural ingredients specifically selected for the unique nutritional and pH requirements of blueberry bushes.
Can I use organic blueberry fertilizer on other berries?
Yes, organic blueberry fertilizer works well on other acid-loving berry plants including raspberries, blackberries, cranberries, and huckleberries. It also benefits acid-loving ornamentals like azaleas, rhododendrons, and camellias. However, berries that prefer neutral soil (like strawberries) may not need the soil-acidifying sulfur component. For strawberries, consider Wicked Organics formulas without added sulfur. Old Cobblers Farm™ Wicked Organics Organic Blueberry Fertilizer is ideal for any berry or plant that thrives in acidic soil conditions.
How often should I fertilize blueberries organically?
Fertilize blueberries organically 1–2 times per year. The primary application should be in early spring before new growth begins, with an optional second application after harvest in mid-summer to support flower bud formation for next year's crop. Organic fertilizers release nutrients slowly, so fewer applications are needed compared to synthetic programs. Supplement with elemental sulfur as needed based on soil pH testing to maintain the 4.5–5.5 range. Old Cobblers Farm™ Wicked Organics Organic Blueberry Fertilizer provides sustained nutrition from each application for simpler organic blueberry care.
Is organic blueberry fertilizer OMRI-Listed?
Yes, Old Cobblers Farm™ Wicked Organics Organic Blueberry Fertilizer is OMRI-Listed, meaning it has been reviewed and approved by the Organic Materials Review Institute for use in certified organic production. OMRI certification verifies that all ingredients meet strict organic standards with no synthetic chemicals or prohibited substances. This gives home gardeners and certified organic blueberry growers confidence that they are using a genuinely organic product. Old Cobblers Farm™ Wicked Organics carries the OMRI seal across its entire organic fertilizer lineup.
