Comparison: Best Slow Release Fertilizer Spikes (Updated | Nov 11th)
But with so many options on the market, how do you know which ones truly deliver? We’ve tested the top contenders to help you find the best fertilizer spikes for your garden, houseplants, or lawn—so you can spend less time fussing and more time enjoying healthier, greener growth.
- Best for vibrant tree boost: Miracle-Gro Tree and Shrub Plant Food Spikes
- Best for fruit yield boost: Jobe’s Garden Fertilizer Spikes
- Best for citrus fruit power: Miracle-Gro Fruit & Citrus Plant Food Spikes
- Best for blooming pot plant: Jobe’s Fertilizer Spikes for Flowering Plants (54 Spikes)
- Best for evergreen nutrient guard: Jobe’s Slow Release Evergreen Fertilizer Spikes
- Best for heritage tree care: The Old Farmer’s Almanac Tree & Shrub Fertilizer Spikes (Box of 6 Spikes – 1.5 Lbs)
- Best for palm & fern vitality: Jobe’s Plant Food Fertilizer Spikes
- Best for six-month feed: Osmocote Smart-Release Plant Food Plus Outdoor & Indoor₁
- Best for balanced growth formula: 10-10-10 Slow-Release Premium Fertilizer – All-Purpose Plant Food for Indoor Outdoor Gardening Vegetables Flowers Lawn Trees Shrubs
- Best for palm nutrient boost: Jobe’s Palm Tree Fertilizer Spikes 10-5-10 Time Release Fertilizer for All Outdoor Palm Trees
Product Comparison: Best Slow Release Fertilizer Spikes
Miracle-Gro Tree and Shrub Plant Food Spikes, For Deciduous, Flowering and Evergreen Trees, 12 Spikes
- Miracle-Gro Tree & Shrub Plant Food Spikes promote vibrant color and foliage for trees and shrubs in your landscape
- These easy-to-use tree food spikes provide nutrition directly to your trees’ roots, where they need it most
- Use with deciduous, flowering, and evergreen trees, also great for acid-loving plants
- Apply plant food spikes once in spring and once in fall by placing tree spikes around the tree’s drip line with at least 3 ft. between each spike
- This package includes 12 Miracle-Gro Tree & Shrub Plant Food Spikes, enough to feed 3 trees with a 4-ft drip line diameter or 1 tree with a 12-ft. drip line diameter
Jobe’s Garden Fertilizer Spikes, Easy Plant Care Slow Release Fertilizer for Fruit and Citrus Plants and Trees, 9 Count
- Package contains 9 fruit and citrus fertilizer spikes and is produced to avoid wasteful runoff, mess, hazards and smells
- Plant fertilizer is formulated with a 8-11-11 NPK to provide fruit and citrus plants nutrients they need to create high yield and vibrant foliage
- Application is simple and should be done twice a year in early spring and late fall or as needed during the growing season
- Jobe’s fertilizer is measured to provide the right amount of nutrients for fruit and citrus plants and trees without risk of over fertilizing
- Jobe’s fertilizer spikes come in a variety of formulas and pack sizes to help provide lush foliage and vibrant color to your lawn and garden
Miracle-Gro Fruit & Citrus Plant Food Spikes
- Promotes more fruit and lush foliage (vs unfed)
- Contains natural ingredients
- Feed once per season in Spring and Fall
- Also great for use on palm trees
- Easy-to-use spikes release nutrients directly into the root zone to help promote strong fruit, citrus, and palm trees
Jobe’s Fertilizer Spikes for Flowering Plants (54 Spikes)
- THE IDEAL FERTILIZER SPIKE for Potted Plants and Hanging Baskets including Begonias, Fuschia, Lobelia, Petunia, Creeping Jenny and more
- SLOW RELEASE: Jobe’s fertilizer spikes are slow release, meaning that they release a small steady amount of nutrients to your plants over time to keep your plants happy and healthy all season long
- EASY-TO-USE: Whether you’re a seasoned gardening pro or just starting your gardening journey, Jobe’s spikes are easy to insert around each plant’s dripline
- NO WASTEFUL RUNOFF, no mess, and no hazards. Jobe’s fertilizer spikes go right to the root of the plant, so there’s no need to worry about fertilizer running off anywhere else around you. Each spike gives your plant the perfect amount of nutrients
- ABOUT JOBE’S: The Jobe’s Company is Based in Waco, Texas and we specialize in home and garden products that make short work out of working in the garden. One garden at a time, we want to make the world a happier, healthier, and more beautiful place
Jobe’s Slow Release Evergreen Fertilizer Spikes, Easy Plant Care for Cypress, Arborvitae, Pine, Cedar, and Many More Acid Loving Trees, 15 Count
- Package contains 15 evergreen fertilizer spikes and are produced to avoid wasteful runoff, mess, hazards and smells
- Formulated with a 13-3-4 NPK to ensure a continuous supply of nutrients below the surface, where the shrubs and tree’s active roots are growing
- Application is simple and should be done twice a year in early spring and late fall
- Jobe’s evergreen fertilizer spikes come pre-measured to provide the right amount of nutrients for your tree and there is no risk of over fertilizing
- Jobe’s fertilizer spikes come in a variety of formulas and pack sizes to help provide lush foliage and vibrant color to your lawn and garden
The Old Farmer’s Almanac Tree & Shrub Fertilizer Spikes (Box of 6 Spikes – 1.5 Lbs)
Jobe’s Plant Food Fertilizer Spikes, Easy Plant Care for All Ferns and Palm Plants, 30 Count
- Package contains 30 fertilizer spikes for palm trees, plants, and ferns and is produced to avoid wasteful runoff, mess, hazards and smells
- Plant fertilizer is formulated with a 16-2-6 NPK to provide palm plants and ferns the nutrients they need to create healthy, lush, and vibrant foliage
- Application is simple and should be done every 60 days
- Jobe’s fertilizer spikes are pre-measured to provide the right amount of nutrients for palm trees and plants without the risk of over fertilizing
- Jobe’s fertilizer spikes come in a variety of formulas and pack sizes to help provide lush foliage and vibrant color to your lawn and garden
Osmocote Smart-Release Plant Food Plus Outdoor & Indoor₁, Granular Fertilizer with 11 Essential Nutrients, 2 lbs.
- Osmocote Smart-Release Plant Food Plus Outdoor & Indoor₁ granular plant food contains 11 essential nutrients and feeds live plants up to 6 full months
- This fertilizer works with virtually all plant varieties and growing conditions
- Each granule is coated with a unique resin that controls nutritional release so plants get what they need when they need it
- Osmocote offers a no-burn pledge, when used as directed
- One 2 lb. container of Osmocote Smart-Release Plant Food Plus Outdoor & Indoor₁ covers up to 75 sq. ft.
10-10-10 Slow-Release Premium Fertilizer – All-Purpose Plant Food for Indoor Outdoor Gardening Vegetables Flowers Lawn Trees Shrubs, 0.5 Quart
- Balanced Nutrition for Healthy Growth: Our 10-10-10 fertilizer provides Nitrogen, Phosphorus, and Potassium in equal amounts, giving your plants the nutrients they need for strong roots, vibrant blooms, and lush growth.
- Efficient Nutrient Release: Our fast-dissolving formula delivers essential nutrients to your plants right after application, promoting immediate growth and providing ongoing nourishment for an extended period—making it easy to keep your garden thriving.
- Fast-Acting and Easy to Use: Designed with a professional-grade formula, it delivers nutrients quickly to help your plants grow healthier and stronger, with visible results in no time. Sprinkle it on moist soil or lightly bury it for effortless fertilizing.
- Safe and Reliable Ingredients: Crafted with high-quality, naturally sourced ingredients, our fertilizer is free from synthetic additives, ensuring a safe and enjoyable gardening experience for you and your plants.
- Suitable for All Plants: This all-purpose fertilizer is perfect for flowers, vegetables, fruit trees, and ornamental plants. It works for any garden, making it a go-to choice for all gardeners.
Jobe’s Palm Tree Fertilizer Spikes 10-5-10 Time Release Fertilizer for All Outdoor Palm Trees, 5 Spikes per Package (3)
- 10-5-10 formula
- 5 palm spikes per selling unit
- Formulated with special micro-nutrients-sulfur, magnesium, iron, and zinc
- Additional nitrogen, phosphorus and potassium supplements other palm growing needs
- Bagged
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.com at the time of purchase will apply to the purchase of this product.
Buying Guide
FAQs
What should I look for when choosing slow‑release fertilizer spikes for trees and shrubs?
Check the NPK ratio to match the plant’s needs, the recommended application frequency, and the coverage area per spike. Look for formulations that target root zones and claim reduced runoff, as these protect the environment and improve nutrient uptake. Also compare the number of spikes per package to gauge overall value.
How do Miracle‑Gro Tree & Shrub spikes compare with Jobe’s Evergreen spikes?
Miracle‑Gro spikes are marketed for both deciduous and evergreen trees with a balanced nutrient mix, while Jobe’s Evergreen spikes use a 13‑3‑4 ratio that emphasizes nitrogen for lush foliage. Miracle‑Gro provides 12 spikes per pack, enough for one large tree, whereas Jobe’s offers 15 spikes for multiple smaller trees. Both promise slow release and minimal runoff, but Jobe’s may be more cost‑effective for larger plantings.
Which spikes are best for fruit‑bearing trees and citrus?
Jobe’s Fruit & Citrus spikes (8‑11‑11 NPK) and Miracle‑Gro Fruit & Citrus spikes both target high‑yield production, but Jobe’s emphasizes a higher nitrogen level for vigorous growth. Miracle‑Gro’s version also highlights natural ingredients and suitability for palm trees. If you prefer a slightly higher phosphorus boost for fruit set, Jobe’s may be the better choice.
Are there spikes specifically designed for potted or hanging basket plants?
Yes, Jobe’s Fertilizer Spikes for Flowering Plants (54 spikes) are formulated for container‑grown varieties like begonias, petunias, and fuchsias. They release nutrients slowly over the season and are sized for easy insertion around a plant’s drip line. This makes them ideal for indoor gardeners who want mess‑free feeding without over‑fertilizing.
How often should I apply these slow‑release spikes?
Most tree and shrub spikes, including Miracle‑Gro and Jobe’s, recommend two applications per year—once in early spring and once in late fall. Palm‑specific spikes from Jobe’s suggest re‑application every 60 days for continuous feeding. Always follow the manufacturer’s schedule to avoid nutrient buildup.
What is the environmental impact of using fertilizer spikes versus granular fertilizers?
Spikes are designed to place nutrients directly at the root zone, which greatly reduces the risk of runoff and leaching compared with broadcast granular products. Brands like Jobe’s and Miracle‑Gro highlight “no‑waste” formulations that minimize odor and mess. For gardeners concerned about water quality, spikes generally offer a greener alternative.
Is it more economical to buy spikes in bulk or to choose a granular product like Osmocote?
Bulk spike packs, such as Jobe’s 30‑spike palm package, can lower the per‑spike cost for large landscaping projects. Osmocote’s granular formula covers up to 75 sq ft for six months, which may be cheaper for wide‑area lawns but requires more handling. Consider the size of your garden and how often you plan to fertilize when evaluating overall value.
Can I use the same spikes for both indoor and outdoor plants?
While many spikes are safe for both environments, some formulas are optimized for specific plant types. For example, Jobe’s Plant Food spikes are tailored for ferns and palms, making them suitable for indoor spaces, whereas Miracle‑Gro Tree spikes are intended for outdoor trees and shrubs. Always verify the product label to ensure compatibility with your planting location.