10 Best Slow Release Fertilizers of 2025

Tested and Reviewed: Top 10 Slow Release Fertilizers deals with expert ratings from 8.1 to a perfect 10

March 2026 Edition

Editor's Choice

9.7

Gardenera

𝐁𝐄𝐒𝐓𝐒𝐄𝐋𝐋𝐄𝐑 10-10-10 Plant Fertilizer Slow Release | 10 10 10 All Purpose Fertilizer for Fruit Trees, Evergreens, Vegetables, Arborvitae, Fig Trees, Shrubs, Pines, Oaks, Flowers [1 Quart]

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Editor's bottom line:

“This slow release fertilizers is the best one we tested. In terms of quality, brand and price, we couldn't ask for more.”

Main Highlights

ALL-PURPOSE PLANT FOOD Balanced 10-10-10 NPK fertilizer supports strong root development, lush foliage, and vibrant blooms for vegetables, flowers, trees, shrubs, and lawns.

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Picked by 397 people today

9.5

Osmocote

Osmocote Smart-Release Plant Food Plus Outdoor & Indoor1 - Granular, Continuous Release Plant Fertilizer with 11 Essential Nutrients, 2 lbs.

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Main Highlights

CONTINUOUS RELEASE NUTRITION: Osmocote Smart-Release Plant Food Plus Outdoor & Indoor1 granular fertilizer contains 11 essential nutrients and feeds live plants up to 6 full months
USE WITH VIRTUALLY ALL PLANTS: This plant food for houseplants, flowers, vegetables, trees, shrubs, roses, and more works in virtually all growing conditions both indoors and outdoors, in containers, raised beds, and in-ground garden.
RESIN COATING: Each granule of Osmocote Plus Outdoor & Indoor1 is coated with a unique resin that controls nutritional release so plants get what they need when they need it
NO-BURN PLEDGE: When used as directed, this Osmocote plant food outdoor and indoor will not burn your plants
COVERAGE: One 2 lb. container of Osmocote Smart-Release Plant Food Plus indoor and outdoor plant food covers up to 75 sq. ft.

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9.5

Osmocote

Osmocote Smart-Release Plant Food Flower & Vegetable - Continuous Release Plant Fertilizer for Vegetables and More, 8 lb.

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Main Highlights

OSMOCOTES HIGHEST TOTAL NUTRIENT FORMULA: 14-14-14 NPK - favored for seasonal vegetables and perennials; use this plant food outdoors to promote strong roots as well as vigorous and bountiful above-ground growth.
HOW TO USE: Use the included scoop to apply 1 scoopful per 4 sq. ft. and mix into the top 1-3 inches of soil; apply this vegetable and flower food to vegetable gardens and mulched areas around ornamental trees/shrubs, and in raised beds.
OSMOCOTE QUALITY: Osmocote is the original slow-release plant food; decades of rigorous field testing confirm product effectiveness with hundreds of plant species in a variety of climate and soil conditions.
OSMOCOTES SECRET: Soil temperature controls how Osmocote flower and vegetable plant food releases its nutrients, and how nutrients are taken up by the plant; replenishment and feeding are in natural harmony.
OSMOCOTE IS MISTAKE-PROOF: Even if over-applied up to 3x the recommended rate, Osmocote does not burn the plant.
COVERAGE: 1 lb. of continous release fertilizer for vegetables and flowers covers 40 sq. ft. (approx. 6½ ft. x 6½ ft.); this 8 lb. container covers 320 sq. ft.

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9.2

GARDENWISE

10-10-10 Plant Fertilizer Slow Release - 10 10 10 All Purpose Granular Garden Fertilizer for Vegetables, Tomato, Arborvitae, Shrubs, Rose, Flowers, Fruit, Fig Trees (1/2 Quart)

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Main Highlights

Balanced 10-10-10 Granular Fertilizer for Outdoor & Indoor Plants: All-purpose plant food with 10% Nitrogen, 10% Phosphorus, and 10% Potassium. Perfect for outdoor vegetable gardens, fruit trees, evergreens, shrubs, lawns, and flowers. Also great for potted plants and indoor gardening. One solution for all your plant needs!
Slow-Release Formula for Continuous Outdoor Feeding: Provides up to 8 weeks of sustained nutrition with fewer applications. Ideal for outdoor lawns, vegetable gardens, fruit trees, and flowering plants. Apply twice per season for gardens and three times per year for trees and shrubs. Less work, more growth!
Promotes Strong Roots, Lush Growth, and Vibrant Outdoor Blooms: Phosphorus supports root health, Nitrogen fuels lush green leaves, and Potassium enhances plant resilience. Perfect for outdoor flowers, tomatoes, peppers, roses, evergreens, and shrubs. Enjoy thriving plants, colorful blooms, and abundant harvests!
Easy-to-Apply Granules for Even Outdoor Coverage: Fine granules spread evenly for maximum soil absorption in outdoor gardens, lawns, and landscapes. Ideal for pines, oaks, banana trees, fig trees, and ornamentals. Just spread, water, and watch your outdoor garden flourish!
Quick-Release Nitrogen for Immediate Outdoor Results: Instant nitrogen boost for rapid growth, combined with slow-release feeding for lasting results. Perfect for outdoor grass lawns, evergreen trees, flowering plants, and vegetables. See your outdoor garden thrive quickly and sustainably!

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9.0

Miracle-Gro

Miracle-Gro Shake 'N Feed All Purpose Plant Food - Outdoor and Indoor Plant Food for In-Ground and Containers, Feeds for up to 3 Months, 4.5 lbs.

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Main Highlights

3 MONTHS OF FEEDING: Miracle-Gro Shake 'N Feed All Purpose Plant Food feeds plants for up to 3 months, and nourishes above and below the soil
GROW STRONGER PLANTS: This plant food contains vital micronutrients to grow stronger, vibrant, and more productive plants (vs unfed plants)
FOR ALL PLANTS: Use this all-purpose plant food outdoor or indoor to feed container plants or plants in outdoor in-ground and raised bed gardens, including flowers, vegetables, and herbs
APPLICATION: Apply this continuous release garden product evenly onto the soil and work into the top 1-3 inches of soil for in-ground plants, or lightly work into the soil of established container plants; water to start feeding; reapply every 3 months
NOURISHES ABOVE & BELOW THE SOIL: Indoor and outdoor plant food contains natural ingredients to feed soil microbes that break down the ingredients into nutrients that support root strength and development which increases water efficiency
COVERAGE: One 4.5 lb. container of Miracle-Gro Shake 'n Feed All Purpose Plant Food feeds up to 180 sq. ft.

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8.8

GARDENWISE

10-10-10 Plant Fertilizer Slow Release - 10 10 10 All Purpose Granular Garden Fertilizer for Vegetables, Tomato, Arborvitae, Shrubs, Rose, Flowers, Fruit, Fig Trees (3 QUARTS)

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Main Highlights

Balanced 10-10-10 Granular Fertilizer for Outdoor & Indoor Plants: All-purpose plant food with 10% Nitrogen, 10% Phosphorus, and 10% Potassium. Perfect for outdoor vegetable gardens, fruit trees, evergreens, shrubs, lawns, and flowers. Also great for potted plants and indoor gardening. One solution for all your plant needs!
Slow-Release Formula for Continuous Outdoor Feeding: Provides up to 8 weeks of sustained nutrition with fewer applications. Ideal for outdoor lawns, vegetable gardens, fruit trees, and flowering plants. Apply twice per season for gardens and three times per year for trees and shrubs. Less work, more growth!
Promotes Strong Roots, Lush Growth, and Vibrant Outdoor Blooms: Phosphorus supports root health, Nitrogen fuels lush green leaves, and Potassium enhances plant resilience. Perfect for outdoor flowers, tomatoes, peppers, roses, evergreens, and shrubs. Enjoy thriving plants, colorful blooms, and abundant harvests!
Easy-to-Apply Granules for Even Outdoor Coverage: Fine granules spread evenly for maximum soil absorption in outdoor gardens, lawns, and landscapes. Ideal for pines, oaks, banana trees, fig trees, and ornamentals. Just spread, water, and watch your outdoor garden flourish!
Quick-Release Nitrogen for Immediate Outdoor Results: Instant nitrogen boost for rapid growth, combined with slow-release feeding for lasting results. Perfect for outdoor grass lawns, evergreen trees, flowering plants, and vegetables. See your outdoor garden thrive quickly and sustainably!

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8.6

GARDENWISE

10-10-10 Plant Fertilizer Slow Release - 10 10 10 All Purpose Granular Garden Fertilizer for Vegetables, Tomato, Arborvitae, Shrubs, Rose, Flowers, Fruit, Fig Trees (4 QUARTS)

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Main Highlights

Balanced 10-10-10 Granular Fertilizer for Outdoor & Indoor Plants: All-purpose plant food with 10% Nitrogen, 10% Phosphorus, and 10% Potassium. Perfect for outdoor vegetable gardens, fruit trees, evergreens, shrubs, lawns, and flowers. Also great for potted plants and indoor gardening. One solution for all your plant needs!
Slow-Release Formula for Continuous Outdoor Feeding: Provides up to 8 weeks of sustained nutrition with fewer applications. Ideal for outdoor lawns, vegetable gardens, fruit trees, and flowering plants. Apply twice per season for gardens and three times per year for trees and shrubs. Less work, more growth!
Promotes Strong Roots, Lush Growth, and Vibrant Outdoor Blooms: Phosphorus supports root health, Nitrogen fuels lush green leaves, and Potassium enhances plant resilience. Perfect for outdoor flowers, tomatoes, peppers, roses, evergreens, and shrubs. Enjoy thriving plants, colorful blooms, and abundant harvests!
Easy-to-Apply Granules for Even Outdoor Coverage: Fine granules spread evenly for maximum soil absorption in outdoor gardens, lawns, and landscapes. Ideal for pines, oaks, banana trees, fig trees, and ornamentals. Just spread, water, and watch your outdoor garden flourish!
Quick-Release Nitrogen for Immediate Outdoor Results: Instant nitrogen boost for rapid growth, combined with slow-release feeding for lasting results. Perfect for outdoor grass lawns, evergreen trees, flowering plants, and vegetables. See your outdoor garden thrive quickly and sustainably!

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8.3

Schultz

Schultz 018065 Spf48270 Slow-Release Bloom Fertilizer 3.5 Lbs, 56 Ounce

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Main Highlights

12-24-12
Size: 3.5 Lbs
Slow Release

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Our Best Overall Choice

Best Choice

9.7

Gardenera

𝐁𝐄𝐒𝐓𝐒𝐄𝐋𝐋𝐄𝐑 10-10-10 Plant Fertilizer Slow Release | 10 10 10 All Purpose Fertilizer for Fruit Trees, Evergreens, Vegetables, Arborvitae, Fig Trees, Shrubs, Pines, Oaks, Flowers [1 Quart]

Free Shipping

Editor's bottom line:

“This is the best one we tested. In terms of quality, brand and price, we couldn't ask for more.”

Main Highlights

ALL-PURPOSE PLANT FOOD Balanced 10-10-10 NPK fertilizer supports strong root development, lush foliage, and vibrant blooms for vegetables, flowers, trees, shrubs, and lawns.

Show Price

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