1. Sunshine Advanced Rain Forest Blend - OMRI-listed


    For growers who want to learn to get the most out of SSA products, we’ve developed a series of Tech Talk articles. These articles cover the details of each blend as well as FAQs we get from growers. Don’t see your question answered here? Enjoy!


    Sunshine Advanced Rain Forest Blend is a nutrient-packed potting soil for awesome container garden performance. It is designed specifically for growing established foliage crops, vegetables, and herbs. The natural and organic blend has slow-release nutrients and provides good drainage to help develop strong, healthy root systems for maximum foliar growth. Plus, Rain Forest Blend contains bio-active mycorrhizae, earthworm castings and humic acid for a growth-boosting formula with supplemental alfalfa, kelp, and feather meal.


    This product is designed specifically for growing established outdoor foliage crops, vegetables, and herbs. It can also be used in indoor growing situations where a heavier mix is needed to keep pots from falling over.


    • Outdoor “heavy” mix
    • Bark is a main ingredient, providing increased weight, density and drainage
    • Starter fertilizer package with kelp and alfalfa meal
    • Contains coir, earthworm castings and compost


    • pH: 5.5 – 6.5
    • Soluble salts: 0.40 – 1.5 mmhos/cm
    • Nitrate: N –10 – 50 ppm
    • Phosphorus: – 5 – 10 ppm
    • Potassium: 50 – 100 ppm
    • Calcium: 8 – 30 ppm
    • Magnesium: 5 – 25 ppm

    This is a slow-release, nutrient-rich growing mix with good drainage. It is formulated to build strong, healthy root systems for maximum foliar growth.

    Sunshine Advanced Rain Forest Blend contains coir (coconut fiber) for nutrient and water retention. The addition of fine bark provides physical stability for long-term growing. The use of compost and earthworm castings adds a slow-release source of nutrients along with beneficial microorganisms. The organic nutrient pack, along with humic acid, alfalfa meal and kelp meal, gives a good dose of starter fertilizer to get plants going. Our endomycorrhizal blend enhances the ability of containerized plants to access the nutrients in the root zone, and the earthworm castings boost microorganism populations, which are beneficial to plant root growth.

    Our Sunshine Advanced Rain Forest Blend formula was trialed in our own greenhouses; we worked to develop a mix with the best combination of water retention, air porosity,  and nutrient availability. Various formulations were tested, using a range of herb and vegetable plants, until we came up with the ideal blend of bark, coir, compost and perlite. In addition, using our in house lab, we examined the roots for mycorrhizal colonization to ensure that Sunshine Advanced Rain Forest Blend would enhance mycorrhizal growth. Ongoing testing in our trial greenhouses ensures that Sunshine Advanced Rain Forest Blend will continue to provide the maximum results you expect from all Sunshine products.

    Sunshine Advanced Rain Forest Blend is designed to provide a perfect background to your own fertility program. We’ve included a starter organic fertilizer, along with humic acid, kelp meal and alfalfa meal, to give an initial boost to your seedlings or transplants and to supply background fertility over the course of your growing season. You should start your own feed program within 14 days of planting or seedling emergence. Mycorrhizae prefer a low-phosphorus feed for optimal growth, so during the plant’s active foliar growth stage, use a high nitrogen, low phosphorus feed such as 16-1-2 or 20-9-20.

    Using endomycorrhizae means you only get the mycorrhizal species that actually work with garden, foliage, vegetable and herb plants. Other growing mixes offer ectomycorrhizae as part of their mycorrhizal blend – but ectomycorrhizae only work for certain trees, such as pines, spruces and firs. Why pay for an ingredient that isn’t going to benefit your plants? Using a growing media with a blend of endomycorrhizae ensures that your plants will derive the maximum benefit from the same fungi that colonize their roots in nature.


    1. What makes Sunshine Advanced Rain Forest Blend unique?
    Sunshine Advanced Rain Forest Blend contains coir, a byproduct of processing coconuts. Coir has unique properties of high aeration coupled with excellent water retention and nutrient retention and is frequently used in growing mixes to aid in rapid rewetting of the mix. The addition of compost helps to retain nutrients as well. Bark is a main ingredient for added container stability and good drainage.

    2. What are mycorrhizae?
    Mycorrhizae are a group of fungi which form a symbiotic relationship with plants in nature. These important fungi colonize a plant’s root system, sending their hyphae out into the surrounding soil to seek out nutrients. It is estimated that 90% of the world’s plants are dependent on mycorrhizae in their native habitats. The addition of mycorrhizae in this growing mix provides for optimized plant performance even in containers.

    3. Why should I use mycorrhizae in my potting soil?
    The same benefits apply to potting soils. Mycorrhizae will help the root system take up nutrients and may provide a healthier, stronger root system. If you transplant into a garden soil, the presence of mycorrhizae will also assist in drought tolerance and will keep growing along with your plant, as it continues to seek out nutrients.

    4. Why does Sunshine Advanced contain an organic fertilizer?
    Our custom designed organic fertilizer consisting of feathermeal and sulfate of potash gives your plants an initial gentle boost of fertility. Sunshine Advanced Rainforest Blend also includes kelpmeal, alfalfa meal and humic acid for improved nutritional value. The organic fertilizer is a low phosphorus feed so it will not interfere with the establishment of the mycorrhizae in the root zone.

    5. So I need to use a low phosphorus feed?
    That is correct. While the mycorrhizae is growing along with your plant, please use a feed containing less than 10% phosphorus. Mycorrhizae will not be active in soils with higher phosphorus levels. Look for a fertilizer where the second number is less than 10.

    6. Where can I go for more information on Sunshine Advanced products?
    You can refer to our Products Page to find additional information on all Sunshine Advanced products. OR…ask us a question in the comments section of this page.

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    1. Bill

      Where can I purchase your Advanced Rain Forest Blend at wholesale or near wholesale prices? I’m in St. Petersburg Florida and am very involved in supporting urban agriculture throughout the city.
      Thank you, Bill Bilodeau

    2. Sunshine Advanced

      Hi Maxx,

      Bark is the major ingredient of Sunshine Advanced Rain Forest Blend. There are about equal amounts of coir and perlite and then a lesser amount of planting mix and earthworm castings.

      Happy Growing!