Jack's 18-8-23 Outdoor
Best nutrient blend for outdoor hemp and cannabis cultivators.
Jack's 18-8-23 Outdoor is a specialized granular nutrient blend designed by Jack's research team for efficient and cost-effective outdoor hemp and cannabis production. This formula is crafted to maintain a potentially acidic pH, ensuring optimal nutrient uptake for thriving plants in high-sunlight environments. It features a perfected N:K2O ratio, balanced with added Magnesium (Mg) and Sulfur (S) for an ideal nutritional profile. This fertilizer helps growers achieve healthy, robust crops by providing targeted nutrition in a convenient 25 lb. package.
$65.00
Owner Satisfaction
4.7
/ 5
Category Rank
50
/ 4425
#50 in Fertilizers
Price vs Category Average
+5%
Above average
NPK Ratio
18823
/ --
Who it's for
- Gardeners seeking to prevent nutrient deficiencies and boost plant health
- Growers prioritizing strong root systems and abundant flower production
- Users needing fast-acting nutrients for immediate plant growth results
Who should skip it
- Budget-conscious shoppers looking for inexpensive, general-purpose fertilizers
- Busy gardeners preferring low-maintenance, slow-release feeding schedules
- Beginners worried about the risks of over-fertilizing sensitive plants
Performance breakdown
Nutrient Density
High-potency NPK ratio delivers concentrated fuel for vigorous outdoor growth.
pH Optimization
Acidic formulation ensures consistent nutrient availability in diverse soil conditions.
Application Ease
Granular consistency allows for uniform distribution across large outdoor plots.
Secondary Nutrient Profile
Added magnesium and sulfur prevent common deficiencies in high-sunlight environments.
Outdoor Resilience
Engineered specifically to withstand the demands of intense, direct sun exposure.
Production Efficiency
Cost-effective formula maximizes yield potential for large-scale hemp and cannabis.
Key Specs
NPK Ratio
18-8-23
Package Weight
25 lb.
Fertilizer Form
Granular
Secondary Nutrients
Magnesium (Mg) and Sulfur (S)
pH Effect
Potentially acidic
Intended Use
Outdoor production
Nitrogen Percent
18%
Phosphorus Percent
8%
Features
- Tailored for outdoor cannabis and hemp
- Maintains optimal pH for nutrient uptake
- Optimized N:K2O ratio for sunlight
- Includes Mg and S for plant balance
- Efficient and cost-effective formulation
- Supports robust plant growth outdoors
- Granular form for easy application
- Provides essential secondary nutrients
What customers say
Customers highly value Jack's 18 8 23 Outdoor for its superior quality and reliable performance. Reviewers consistently report achieving deep greening and robust growth rapidly after use. This product is widely regarded as an excellent value, offering professional grade results without a high cost. Its consistent seasonal feeding simplifies lawn maintenance, making the process straightforward and rewarding for users seeking dependable lawn nutrition.
Know before you buy
Yes, this blend was developed by Jack's research team specifically to meet the nutritional demands of outdoor hemp and cannabis production. While it is tailored for these crops, its balanced NPK ratio also makes it suitable for vegetables, trees, and shrubs.
The formula is designed to maintain a potentially acidic pH in the soil, which is critical for maximizing nutrient uptake. This ensures your plants can efficiently absorb the minerals they need, even in high-sunlight outdoor environments.
The high potassium content (23%) is specifically balanced against the nitrogen levels to support plants exposed to intense, direct sunlight. This ratio helps maintain plant structure and vigor throughout the summer growing season.
Yes, this blend includes essential secondary nutrients, specifically Magnesium (Mg) and Sulfur (S). These are included to ensure a balanced nutritional profile that supports overall plant health and metabolic function.
As a granular product, it is designed for straightforward application to the soil around your plants. It is best applied during the summer months when plants are in their peak growth phase to provide consistent, targeted nutrition.
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$65