Fish and kelp is the fertilizer I reach for when plants need a fast, gentle boost. The fish side brings nitrogen that gets leafy growth moving, and the kelp side adds trace minerals and natural growth compounds that help plants handle stress. It is a liquid, so it gets to the roots quickly instead of waiting weeks to break down like a granular feed.
Why it earned a spot in my garden
- It works fast. Liquid nutrients reach the roots right away, so plants can green up within a week or so.
- It is organic. It feeds the soil life along with the plant, which matters to me since all of my growing is in containers.
- It is easy to dose. Measure, mix in a watering can, and pour. No spreaders and no guesswork.
- It is gentle. Used at the label rate, it is a mild feed that is unlikely to burn plants.
How I use it
- Shake the bottle well. The good stuff settles.
- Mix it into a watering can at the rate on the label.
- Water the soil around the base of the plant, not just the leaves.
- Repeat every two to three weeks while plants are actively growing.
I pair it with a slow release granular feed like my 4-4-4 vegetable fertilizer at planting. The granular feed is the steady base, and the fish and kelp is the quick top-up.
Tips for best results
- Water first if the soil is bone dry, then feed. Roots take it up better from moist soil.
- Ease off nitrogen once fruiting plants like tomatoes and peppers start setting fruit, or you can end up with lots of leaves and fewer fruit.
- Rinse your watering can after each use so it does not get funky.
Who should skip it
If you only grow houseplants in a small apartment, the smell may not be worth it. A synthetic or odorless liquid feed will be easier to live with indoors. It is also not a good fit for most hydroponic systems, since organic liquids can clog pumps and drippers.
Common questions
Does fish and kelp fertilizer smell?
Yes, there is a fishy smell when you mix and apply it. It fades within a day or so outdoors. I avoid using it on indoor plants for that reason.
How often should I use fish and kelp fertilizer?
I feed every two to three weeks during the growing season at the label rate. Always follow the dilution on the bottle, since more is not better with liquid feeds.
Can I use it as a foliar spray?
Many gardeners do. Dilute it to the label's foliar rate, spray early in the morning or in the evening, and avoid spraying in full midday sun.
Ready to try it in your garden?
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