April 20, 2025
As you likely know, I like to fish. A lot. Fortunately, I tend to have a lot of fish carcasses and hate to see anything go to waste. I’ve been experimenting with different ways to compost these fish. It’s 2025 and spring is here and while it’s peak fishing time, it’s also time for planting the garden.
Fish carcass fertilizer
I’ve heard people talk about using fish carcasses in the garden under their plants as a natural slow release fertilizer. Some swear by the results saying their plants with the fish under them out perform others in their garden. So, this year I thought I’d test the theory.
This concept is an ancient practice. The theory is as the fish breaks down, it releases essential plant nutrients—primarily nitrogen, phosphorus, and potassium—directly into the root zone. This provides a strong and ongoing fertilizer source to the plant throughout the season.
The plan
I’ve planted one row of tomato plants approximately two feet apart. Every other plant received a fish under it about 14” deep – approximately 5″ below the rootball of the plant. Likewise, I planted a row of squash and zucchini. Alternating these plants and adding fish under 4 of the 6 planting locations (I planted 4 seeds of each type in each location).
In theory, the he breakdown of the fish oils and bones should place plant living nutrients right at the roots – if I’ve not gone too deep with the fish.
Initial testing
Living in the woods, there is a lot of predator pressure. So I buried the fish approximately 17” under the squash and 14” under the tomatoes. I gave each location a couple days before planting it and I’m happy to report nothing found or dug into the buried fish.
But will it work
So now, we wait. Each plant will get water and pruned similar. Each plant will get fertilized the same. The goal is to care for each plant the same way and see if we can track any real difference in production.
Save this post and check back as the season progresses to see how this experiment turns out! I’ll post updates as we progress.
Update 1 : 5-27-2025
Despite the glowing successes you see on YouTube, sometimes gardening doesn’t go as planned. This year I’ve faced challenges I’ve never faced before – specifically with germination
Out of approximately 50 green bean plants, maybe 10 came up. Out of 2 rows of black-eyed peas I only had 7 germinate. Similar, with the squash and zucchini I had less about a 10% germination success. Likewise, I planted an entire row of Okra – and literally, none of them came up. I must have been working with bad seed.
I’ve replanted the green beans and now have almost 100% growing. They are strung and starting to do their thing. I’ve also replanted the green beans. I still have a few that didn’t germinate, but the overall results are much better. I’ve also re-tilled and completely replanted the okra. It can be slow to pop up, so we’ll give it a couple weeks and see what happens. This new run of okra was all new seed.
Tomatoes, I planted transplants. Out of 12 in the ground I lost 3. All 3 were side by side and in the center of the row. I have more seedlings growing to replace them when they get a little stronger. Two of the dead tomato plants were one with fish carcasses under them, but I don’t think the fish would be factoring in just yet.
In between my two last posts I also planted watermelon which is starting to sprout. Cucumbers are also doing well.
So, the germination issues have set up back, but hopefully we are on track now. I’m curious to see if the squash and zucchini replanting will germinate.