powdered seaweed fertilizer

25kg Calcified Seaweed Fertilizer (Powder)

25kg Calcified Seaweed Fertilizer (Powder)

25kg Calcified Seaweed Fertiliser (Powder) – Organic Soil Conditioner

  • Breaks down heavy soils and improves soil structure
  • Promotes stronger root systems and vigorous plant growth
  • Only needs to applied once every three years

Calcified Seaweed works by breaking down heavy soils and encourages the development of beneficial micro-organisms. It improves the soil structure with nutrients and trace elements, helping plants to grow stronger root systems leading to healthier and more vigorous plant growth . Rich in minerals Calcified Seaweed can also be used as a lawn dressing early in Spring.

This product should not be used around ericaceous (acid-loving) plants.


Use at 60-75g per square metre.

Any rates that we recommend should also take into account the nutrient levels in your own soil. In studies it has been found that many private gardeners are using up to 5 times the amount of fertiliser than is necessary. Our recommendation is that you either invest in a soil testing kit or send a sample to a soil analyst service for advice before using fertilisers. We also advise caution with regard to waterways as overuse can cause run off and contamination. Applying fertilisers little and often and then retesting your soil is good practice.

Fertilisers usually have their nitrogen, phosphate and potassium levels expressed as ‘NPK’ values. Nitrogen promotes green leafy foliage; phosphate promotes strong root systems and potash promotes fruit and flower production and general plant health.

Fertiliser manufacturers may legitimately include some inert material like clay or sand into their products in order to act as a carrier to ensure that the correct levels of nutrient are present in that particular compound.

This product can be offered in pallet quantities of 10 bags plus. We also offer pallets of mixed products. If you require a pallet price, please contact us by e-mail at [email protected] with your full delivery address (including postcode) for a quote.

Write a review

Your Review: Note: HTML is not translated!

Rating: Bad Good

Enter the code in the box below:

25kg Calcified Seaweed Fertilizer (Powder) 25kg Calcified Seaweed Fertilizer (Powder) 25kg Calcified Seaweed Fertiliser (Powder) – Organic Soil Conditioner Breaks down heavy soils

Seaweed Powder

Provides nutritional support, promotes balanced growth, and improves crop quality.

Ascophyllum nodosum and potassium hydroxide.

Soluble Potash (K2O). 16.0%

Derived from: Ascophyllum nodosum and potassium hydroxide.

Product sizes and weights

50 lbs (22.72 kg)
1225 lbs (Supersack) (555.65 kg)

Download Label

Download SDS

Download Fact Sheet

Download OMRI Certificate

Download CDFA Certificate

Frequently Asked Questions


How is Grower’s Secret Seaweed Powder applied?

Grower’s Secret Soluble Seaweed powder is a kelp product that can be used as part of a comprehensive nutrient management program. It can be applied as a foliar spray, a root soak or through a drip application on all agricultural crops including trees, woody plants and turf. Soluble seaweed is used to enhance chlorophyll content, root growth and flower set and development and helps improve crop quality.

Will Grower’s Secret Soluble Seaweed Powder damage or burn my crops?

Grower’s Secret Soluble Seaweed powder should only be used according to plant needs and suggested use rates. If you have not used a product before, we recommend that you conduct a small jar compatibility test before mixing products to be applied at the same time in the field and also conducting a small infield phytotoxicity test before you apply it in wide-scale use.

What is the shelf life of Grower’s Secret Seaweed Powder Kelp?

About two years if kept away from moisture and sealed in the original container.

What packaging sizes is Grower’s Secret Soluble Seaweed Powder sold in?

Grower’s Secret Soluble Seaweed powder is available in 50 lb. bags and 1,125 lb. super sacks.

Can Grower’s Secret Soluble Seaweed powder be used through drip systems?

Grower’s Secret Soluble Seaweed can be applied through a drip system at suggested use rates. Check system calibration and function to assure even distribution and proper application rates are being applied.

What is the proper use rate for Grower’s Secret Soluble Seaweed powder?

Growers can apply 14-21 oz of Soluble Seaweed powder in a foliar application in sufficient water for for coverage. Soil applications should be applied at a rate of 2-5 pounds per acre. All applications should be made according to plant needs as determined form plant and soil analysis.

Find great deals on Grower’s Secret for Organic Seaweed. We sell the finest organic soluble seaweed powder. Buy seaweed powder from us at good prices.