Neptune's Harvest Organic Fish & Seaweed Fertilizer
Best organic nutrient for thriving gardens and healthy plants.
Neptune's Harvest Organic Fish & Seaweed Fertilizer is a gardener's go-to for boosting plant health and productivity. This 2-3-1 blend combines hydrolyzed fish (75%) and nutrient-packed seaweed (25%) to create an all-purpose, organic liquid fertilizer that works wonders on everything— vegetables, fruits, flowers, trees, and even container plants, outdoors or indoors. OMRI Listed for organic use, this environmentally friendly formula delivers essential nutrients for strong, vigorous plants. This powerful blend helps plants handle stress better—whether it's heat, drought, or cold—and naturally strengthens resistance to pests and disease. Expect bigger harvests, more flowers, and bolder colors. Fruits and veggies grow larger and taste better, plus they stay fresh longer. By increasing natural sugar levels in plants, this fertilizer even makes them less appealing to pests, so you'll have fewer bug problems in the garden. Use Neptune's Harvest as a foliar spray for a quick pick-me-up or as a soil drench to enrich the ground and support beneficial microbes. It's also great for seed starting —just soak seeds in a diluted mix (1 tsp per cup of water) to speed up germination. Young plants get a strong start, developing deeper roots, larger leaves, and faster growth. This formula is made with wild-caught North Atlantic fish, processed using a cold method to preserve heat-sensitive nutrients and enzymes. Unlike fish emulsions, it contains all the natural amino acids, vitamins, Omega oils, and growth hormones plants need. The added seaweed (Ascophyllum Nodosum) is a natural biostimulant packed with trace minerals and plant-boosting compounds that encourage fast, healthy growth and stronger root systems.
$64.99
More Fish & Seaweed Fertilizer Options
Owner Satisfaction
4.5
/ 5
Category Rank
3091
/ 4425
#3091 in Fertilizers
Price vs Category Average
+5%
Above average
SKU
44507
Who it's for
- Gardeners prioritizing natural, comprehensive nutrition for their plants and soil
- Eco-conscious growers seeking a chemical-free, environmentally friendly plant food
- Cultivators aiming for healthier, more robust plants with improved stress tolerance
Who should skip it
- Home gardeners sensitive to strong smells or those with indoor plants
- Urban gardeners or those in areas with wildlife activity
- Busy individuals preferring low-maintenance, set-it-and-forget-it fertilization methods
Performance breakdown
Nutrient Bioavailability
Cold-processed method preserves essential enzymes and heat-sensitive growth hormones.
Application Versatility
Seamlessly transitions between foliar sprays, soil drenches, and seed soaking.
Organic Integrity
OMRI certification ensures strict adherence to high-quality organic gardening standards.
Stress Resilience
Seaweed biostimulants significantly bolster plant defenses against heat and drought.
Pest Deterrence
Increased sugar levels naturally discourage common garden pests and insects.
Growth Stimulation
Promotes rapid root development and vigorous foliage for all plant types.
Key Specs
SKU
44507
Size
36 Ounce
Special Features
Fertilizer, Indoor Growing, Made in USA, Tomato aids
State Shipping Restrictions
GU, PR, VI
NPK Ratio
2-3-1
Fertilizer Source
Organic, Natural
OMRI Listed
Yes
Country of Origin
USA
Features
- All-purpose organic liquid fertilizer
- Boosts plant health and productivity
- Strengthens resistance to pests and disease
- Improves fruit and vegetable taste and shelf life
- Promotes faster germination and stronger root systems
- Made from wild-caught North Atlantic fish and seaweed
- OMRI Listed for organic gardening
- Versatile application methods
What customers say
Customers consistently praise this organic fertilizer for its remarkable effectiveness in promoting vigorous plant growth and vibrant health across diverse gardens. While its distinct fishy aroma is frequently noted, users overwhelmingly report visible improvements in foliage, blooms, and yields, affirming its high quality. Many find its liquid application simple and appreciate the natural benefits. The product is largely seen as a valuable investment for cultivating robust, thriving plants, despite the initial smell.
Know before you buy
Yes, it is suitable for indoor plants, though keep in mind that it is a fish-based product and may have a distinct scent immediately after application that typically dissipates quickly.
The cold-processing method preserves heat-sensitive nutrients, amino acids, and enzymes that are often destroyed in standard fish emulsions, ensuring your plants receive the full spectrum of natural growth hormones and vitamins.
Absolutely. You can soak your seeds in a diluted mixture of one teaspoon per cup of water to help speed up germination and give young seedlings a stronger, more vigorous start.
A foliar spray is applied directly to the leaves for quick nutrient absorption, while a soil drench is applied to the base of the plant to nourish the root system and support beneficial soil microbes.
While it is not a pesticide, it increases the natural sugar levels in plants, which makes them less attractive to many common garden pests and helps the plant naturally strengthen its resistance to disease.
Yes, this product is OMRI Listed, meaning it has been independently verified to meet the strict standards required for use in organic gardening.
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