Seaweed Fertilizer
Liquid seaweed fertilizer packed with natural growth compounds from kelp. Boosts rooting, stress tolerance, and vigor in every plant you feed.
Simply mix it with water as directed for an easy way to provide consistent nutrition throughout the growing season.
Why You'll Love It
- Nutrient Uptake A kelp biostimulant that supports how well plants take up nutrients.
- Stress Resilience For transplant shock and plants pushing through heat or drought.
- Complete Nutrition Filtered kelp blended with chlorella and spirulina for broad nutrition.
Made by growers
More than a bottle on a shelf.
- Talk to real plant people. The team that mixes the formula answers your email.
- Made in-house, in the USA. Every bottle mixed and filled by us, not a third party.
- We're growers, not resellers. We use this on our own plants before it ships.
- Bundle savings only here. Pair any two TPS formulas — your order ships free.
Seaweed Fertilizer — an ultra-premium filtered kelp biostimulant blended with chlorella and spirulina, made to boost plant resilience and nutrient uptake rather than to feed plants with NPK. The natural growth compounds in seaweed help plants handle stress and take up nutrients more effectively, so the fertilizer you're already using works better and plants stay vigorous through heat, transplanting, and seasonal change.
How to Use Seaweed Fertilizer
| Method | Amount | How Often |
|---|---|---|
| Watering can | 2-4 tsp per gallon of water, then water as usual | Spring & Summer: apply once weekly |
| Watering can | Same dilution | Fall & Winter: every 4 weeks |
| Hose-end sprayer | Set dial to 1 Tbs setting | Spring & Summer: apply once weekly |
| Leaf misting (optional) | 1 tsp per quart of water, spray plants weekly | weekly |
This is a biostimulant that supports plant health and uptake — use it alongside your regular fertilizer, not in place of it.
What's Inside
This is a seaweed biostimulant rather than an NPK fertilizer, so there's no nitrogen-phosphorus-potassium ratio — its value is in natural plant compounds rather than mineral nutrients. It's built on ultra-premium filtered Ascophyllum nodosum kelp, which carries natural growth-promoting compounds, hormones, and trace elements that support root growth, stress tolerance, and nutrient uptake. Filtering makes it clean enough to run through a sprayer or drip line without clogging.
Beyond the kelp: it adds chlorella (Chlorella vulgaris) and spirulina (Arthrospira platensis), two nutrient-dense microalgae that bring additional amino acids and plant-supporting compounds, with citric acid to stabilize the liquid. The point of the blend is resilience and uptake — helping plants recover from transplant shock, handle heat and drought, and get more out of the nutrients they're fed. Because it doesn't supply meaningful NPK, use it to complement your feeding program, not to replace it.
Made For
Made as a resilience and uptake booster for any plant — vegetables, flowers, lawns, trees and shrubs, and houseplants — used alongside your regular fertilizer, and especially useful around transplanting, heat, or other stress.
Problems It Solves
- Transplant shock and slow establishment
- Plants struggling through heat or drought stress
- Poor nutrient uptake despite regular feeding
- Wanting a natural boost to overall plant vigor
FAQs
How often should I use seaweed fertilizer?
In spring and summer, apply once weekly at 2-4 tsp per gallon in a watering can, then water as usual, or use the hose-end sprayer on the 1 Tbs setting. In fall and winter, cut back to once every 4 weeks. Because it's a biostimulant rather than a feed, it's gentle and hard to overapply, but weekly use through the growing season is where you'll see the resilience and uptake benefits build up.
What's the difference between seaweed fertilizer and regular fertilizer?
Regular fertilizer supplies nitrogen, phosphorus, and potassium that feed the plant's growth. Seaweed fertilizer is a biostimulant — it provides natural growth compounds, hormones, and trace elements from kelp and microalgae that help plants take up nutrients and handle stress, but very little NPK. It has no fertilizer ratio because feeding isn't its job. Use the two together: your fertilizer feeds the plant, and this helps the plant make the most of it.
Can seaweed fertilizer be my only plant food?
No — it doesn't supply meaningful nitrogen, phosphorus, or potassium, so it can't replace a fertilizer. A plant given only seaweed would slowly run short on the nutrients it needs to grow. Think of it as a supplement that improves resilience and uptake, used alongside a complete fertilizer. It's one of the most useful add-ons for a feeding program, but it works with a fertilizer, not instead of one.
Does seaweed fertilizer help with transplant shock?
This is one of its best uses. The natural compounds in kelp support root development and help plants handle the stress of being moved, so many gardeners apply seaweed at transplanting and after. It won't guarantee a plant survives a rough transplant, but it supports recovery alongside good watering and placement. Use it when setting out seedlings, potting up, or moving plants, and continue through the establishment period.
When will I see results?
Biostimulant benefits are gradual and show up as steadier, more resilient growth rather than a dramatic green-up — you may notice better recovery from stress and stronger root and overall vigor over a few weeks of regular use. It works best as part of an ongoing program, where the resilience and uptake benefits compound across the season, rather than from a single application.
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