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Calphos Soft Rock Phosphate (25 lb bag)
Calphos Soft Rock Phosphate (25 lb bag)
- Ships Nationwide
Boost soil fertility and support strong root development with Calphos Soft Rock Phosphate, a natural source of phosphorus and calcium. This finely ground mineral powder provides essential nutrients that promote vigorous plant growth, improve flowering, and enhance fruit and vegetable production. Ideal for natural gardening, Calphos releases nutrients slowly over time, ensuring long-term benefits for soil health.
Phosphorus plays a crucial role in energy transfer, root establishment, and bloom formation, while calcium strengthens cell walls and improves overall plant resilience. For a deeper understanding of phosphorus's impact on plant health, you might find our article on How to Use Fertilizers—Soft Rock Phosphate insightful.
Calphos Soft Rock Phosphate can be applied before planting or used as a top dressing throughout the growing season. For specific guidance on phosphorus application for bulbous plants, refer to our blog post What Phosphorus is Right For Your Bulbs?
Key Benefits:
- Averages 20% P2O5 (3% immediately available), 18% Calcium
- Use at 5 lb per 100 square feet or 1 ton per acre on phosphate-deficient soils, less on fertile soils
- Trees and perennials in vegetable gardens for flowering plants, use 1-10 lb per planting hole, depending on plant size
- Supplies phosphorus (P) and calcium (Ca) for up to 5 years after application, depending on the crop
- Provides calcium for strong cell structure and plant resilience
- Improves soil microbial activity and reduces nutrient loss
Improve soil structure and encourage abundant plant growth with Calphos Soft Rock Phosphate. This natural mineral fertilizer provides essential nutrients that help plants establish deep roots, produce vibrant blooms, and yield high-quality fruits and vegetables.
Learn More About Soil Health and Fertilization:
- How to Use Fertilizers—Soft Rock Phosphate
- What Phosphorus is Right For Your Bulbs?
- How to Use Fertilizers—Rock Dust
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Shipping & Returns
Shipping & Returns
SHIPPING:
Outdoor Living & Recreation, Home & Garden products ship nationally & some internationally. The national/international shipping fee is calculated at checkout using your shipping address and choice of shipping provider if applicable. Products marked with free shipping will be free shipping at checkout. Once your lifestyle, home & garden order is fulfilled we'll send the tracking information to your email.
RETURNS: 30 day returns.
We accept returns of unused products that are defective or not defective. Your return must be processed within 30 days of the date of purchase. We will provide a shipping label by email, you are responsible for bringing the return to the shipping provider.
FREIGHT PRODUCTS: no returns or exchanges.
There are no returns, exchanges or refunds for products delivered via freight.
REFUNDS:
The cost of the return shipping and a 6% credit card processing/restocking fee will be deducted from your refund amount. The refund balance will be distributed to you once the returned product is received and processed.
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Let customers speak for us
from 45 reviewsGreat job from growing to shipping
Quality was excellent. Perfect for my Dad’s grave site, honoring a proud Marine.
Appreciate the extra effort to get the product to me when needed. The delivery was made with speed and consideration, very much appreciated
Very nice slim design. They hold the poles close to the wall and well organized. Very simple install
Excellent communication and price. Will use them again!!!
Love this Compost! My garden does great every year and it's because of
this great Compost Mix. I would not use anything else.
Great dirt and great communication
Started a new garden and it seems to be helping all of my new starter plantings
Product was great! Ordered some seeds as part of a gift along with a gardening apron. Was a quality item, arrived quickly and it was a big hit!
Super fast service and answered all my questions!
Great service each time I used them, 3 times now.
He delivered great organic topsoil the same day. Excellent subsurface for sod. Friendly and fast, very careful during delivery.
The mulch was great. No junk in it like the bagged stuff. AsS with all outdoor projects weather is a thing. They were understanding of delays and changes.. And when the day came for delivery, there was plenty of communication and showed up on time. Plus the price was right!
I am very happy with my soil purchase! Great company to do business with! I highly recommend!
It works well. I just wish it had some residual to it so I wouldn't have to spray every few weeks.