Rock Phosphate

Rated 5.00 out of 5 based on 4 customer ratings
(4 customer reviews)


Why Use It?

Long-term, slow-release calcium and organic phosphate. builds up native and depleted soils.

Product Documents

Not Available in California

Product Description


Product form:

Dry powder

NPK analysis:


Primary function/use:

Slow-release phosphate fertilizer.

Other product highlights:

A good alternative to bat guano. Product is 20% total phosphate and 3% available phosphate.

Product designation:


Best suited for:

Well suited for amending and enhancing the soil.

Directions For Use

When and where to use:

Start with early season soil preparation and supplement as needed during grow cycle.

How to apply:

Sprinkle evenly around base of plant or till into soil before planting.

How to mix:

Vegetable Gardens: 4-6 lbs. per 100 sq. ft.

Trees & Shrubs: 1 lb. per one inch diameter of tree.

Perennials & Roses: 1/2 cup per each new plant


Ensure bag is properly sealed and stored in cool, dry, dark place.

All items are shipped using USPS Priority Mail, unless otherwise requested and arranged by the customer, prior to order completion.Free Shipping

All orders ship within 48 hours of order confirmation and as always FREE SHIPPING in the USA. After successfully placing an order from you will receive an order confirmation email with the details of your order to the email address provided.

Once your order has shipped you will be emailed specific tracking information.

To check the status of an order please visit our “View Order” page.

Gift Cards are electronically delivered to your email address.

State of Idaho is not an option for shipping any of our products. If you are in the State of Idaho, please contact us direct.

Kelp4less Disclaimer

While Kelp4less has made every effort to ensure accuracy of information on its website and labels, Kelp4less assumes no responsibility or liability for the use and results of any of it’s products.

The purchaser and the end user of Kelp4less products assumes sole responsibility and liability for product use, results and disposal. Kelp4less makes no guarantees either express or implied.

4 reviews for Rock Phosphate

  1. Rated 5 out of 5

    Chad (verified owner)

    Phosphorous isn’t very mobile in soils, but this is an affordable way to premix and supply ample phosphorus for big blooms. Not recommended as a top dress, mix in before planting.

  2. Rated 5 out of 5

    JJayW (verified owner)

    A great product if you have a plant that is root heavy. My hops and Flying Dragon (Citrus trifoliate) are really happy with it.

  3. Rated 5 out of 5

    Carol Nelson (verified owner)

    When added to my garden fertilizer mix, my plants bloom and produce at an amazing rate (side dressing along rows). It’s nice to have an affordable source for soft rock phosphate and all the other ingredients in my fertilizer. The delivery time is excellent. My rural postal delivery guy even knows if it’s a big heavy box from Kelp4Less just put it on the table in the garden shed!

  4. Rated 5 out of 5

    randall (verified owner)

    This product is tremendous and works well with my dry mixes and I will use this my entire life and works well with fish bone meal, this is a must have folks – would recommend this to all my friends

Add a review

Your email address will not be published. Required fields are marked *

You may also like…