Osmocote Smart-Release Plant Food Plus Outdoor & Indoor Granular Fertilizer
Best long-lasting fertilizer for busy gardeners managing diverse indoor and outdoor plants.
Nourish your plants for up to six months with Osmocote® Smart-Release® Plant Food Plus Outdoor & Indoor. This advanced formula is enriched with 11 essential nutrients, making it suitable for nearly all plant varieties and growing conditions. It comes with a no-burn pledge when used as directed. As the original slow-release plant food, Osmocote's effectiveness is proven through decades of field testing across numerous plant species and environments. Each granule contains a 15-9-12 NPK ratio, along with micro and secondary nutrients, ensuring balanced feeding controlled by soil temperature for natural nutrient uptake.
$14.99
Owner Satisfaction
4.7
/ 5
Category Rank
50
/ 4425
#50 in Fertilizers
Price vs Category Average
-76%
Below average
Fertilizer type
Synthetic
/ Synthetic
Who it's for
- Busy gardeners wanting a set-it-and-forget-it feeding schedule
- Novice plant owners worried about accidental root damage
- Serious growers seeking comprehensive, all-in-one plant nutrition
Who should skip it
- Budget-conscious shoppers looking for the lowest upfront cost
- Gardeners in extreme climates needing consistent, year-round nutrient delivery
- Owners of struggling plants requiring an immediate nutrient boost
Performance breakdown
Nutrient Longevity
Six-month release cycle minimizes the need for frequent reapplication.
Versatility
Balanced formula adapts seamlessly to both indoor and outdoor environments.
Application Safety
Smart-release technology effectively eliminates the risk of fertilizer burn.
Nutrient Profile
Comprehensive blend of eleven essential nutrients supports diverse plant health.
Ease of Use
Simple sprinkle-and-mix application makes feeding plants effortless for beginners.
Release Precision
Temperature-dependent delivery aligns nutrient availability with natural plant growth cycles.
Key Specs
Fertilizer type
Synthetic
Form
Granules
NPK ratio
15-9-12
Release rate
6 months
Net content statement
2 lb
Coverage area
75 sq. ft.
Nitrogen
15%
Phosphorus
9%
Features
- Controlled feeding with Smart-Release® technology
- Fortified with 11 essential nutrients
- Suitable for all plant varieties
- No-burn pledge for safe use
- Nutrient release synchronized with plant needs
- Feeds plants for up to 6 months
- Ideal for indoor and outdoor plants
- Proven effectiveness over decades
What customers say
Gardeners consistently praise the exceptional ease of use and reliable performance of this product. The smart release technology ensures plants receive steady feeding for months, significantly reducing the need for frequent reapplication. This low maintenance approach yields visible, healthy growth for both indoor and outdoor plants. It has become a trustworthy, high quality staple for achieving effortless gardening success.
Know before you buy
The granules are coated with a semi-permeable resin that releases nutrients based on soil temperature. As the soil warms and your plants begin to grow, the fertilizer is released at a rate synchronized with the plant's natural uptake needs.
Yes, this formula is designed for both indoor and outdoor use. Just be sure to use half the recommended outdoor application rate when feeding your indoor houseplants.
Osmocote offers a no-burn pledge when the product is used according to the label directions. Because the nutrients are released slowly over time rather than all at once, it is much safer for delicate root systems than traditional quick-release fertilizers.
You only need to apply it once every six months. The granules provide a steady, consistent supply of 11 essential nutrients throughout that entire period.
This product has a 15-9-12 NPK ratio, meaning it contains 15% nitrogen for foliage growth, 9% phosphorus for root and bloom development, and 12% potassium for overall plant health. It also includes secondary and micro-nutrients to ensure a balanced diet for almost any plant variety.
Sprinkle the recommended amount of granules evenly onto the soil surface, then mix them into the top 1 to 3 inches of soil. After incorporating the fertilizer, water the area thoroughly to begin the activation process.
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