Product Review: Neptune’s Harvest Fertilizer

I HOPE YOU DON’T MIND, BUT I’M GOING TO CONTINUE in my string of posts about smelly stuff. This time it’s about liquid seaweed and fish fertilizer, and although Neptune’s Harvest would have you believe that it smells like a day at the beach, that isn’t exactly true.

That’s not to say that I don’t recommend this organic fertilizer. I found that it works exceptionally well, encouraging dark green leaves and leaf growth on a number of my favorite garden plants, e.g., strawberries, tomatoes, zucchini and more. I use it when I want to encourage growth of both established plants and seedlings. Although when I use it on seedlings I dilute it to half strength to avoid damaging the tender plants.

As you might expect, Neptune’s Harvest is derived from fish and seaweed. You can see a little bit about how the Gloucester, Mass. company makes their liquid fertilizer in this video from New England Cable News Network (NECN).

From my research, I’ve learned that fish emulsion and fish fertilizer are not the same exact thing. Neptune’s Harvest also has seaweed only fertilizer and a hydrolyzed liquid fish fertilizer. If you want to get into the technical differences between emulsion and fish fertilizer, see this webpage from The Organic Gardener on fish emulsion.

Very economical

I found NH’s fish and seaweed mix to be very economical. I paid $10 for an 18 ounce bottle that has lasted me about two years. Today, a 1 quart bottle costs $25.55 on their website, so in the last two years the price has gone up about $.24 an ounce. I’m sure you can find it for less at a local garden center or on the web.

Normally, I would encourage readers to make their own soil amendments, but just the thought of making fish and seaweed fertilizer turns my stomach. Here’s a video on how one person makes a fish fertilizer and compost tea mixture. I must say that I found this video of this attractive, young lady casually talking about something as awful as blending fish in a food processor completely ironic — but also captivating. One thing’s for sure, I’ll never try it. My recommendation: pay the price for this product.

Downsides to consider

There’s only a couple of downsides to consider when using the product as directed. First, don’t get any on you if you can help it because the smell is terrible and it doesn’t come off easily. Second, when I used it on tomato and cucumber seedlings, I found that about a week after planting outside an animal dug up the plants thinking that there must be something good’n fishy to eat under the plants. More than likely, it was our resident skunk that did the damage.

Another product that is pretty popular is Alaska Fish Fertilizer. I haven’t tried it, but you may want to look into it. I hesitate to try a product when I can’t easily figure out who manufactures it.

Let me know what your experiences been with organic fertilizers by commenting below. I’m sure my readers will find your experience extremely helpful.

If you would like to purchase Neptune’s Harvest Fish & Seaweed Fertilizer, please purchase it using this link because I receive a small amount of money if you buy it from here.

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