1. Sunshine Advanced Ultra Coir - OMRI-listed


    For growers who want to learn and 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? Feel free to ask our experts any question you may have in the comments section below. Enjoy!

    Sunshine Advanced Ultra Coir was designed specifically for growing indoor and outdoor foliage crops, vegetables, herbs and other consumable crops. Highly recommended for indoor use with crops that need a lot of water, although close monitoring of water retention is important to make sure they do not get too much water. If using outdoors, containers need to be heavy so that they will not blow over in windy situations.



    • Indoor and Outdoor growing medium with maximum water retention capabilities
    • Coir mix with added peat moss and perlite
    • Non-bark, non-compost mix


    • pH – 6.00 – 7.00
    • Soluble salts – 1.5 – 2.5 mmhos/cm
    • Nitrate N – 25 – 60 ppm
    • Phosphorus – 1 – 10 ppm
    • Potassium – 150 – 450 ppm
    • Calcium – 30 – 60 ppm
    • Magnesium – 10 – 25 ppm

    Sunshine Advanced Ultra Coir is formulated to maintain maximum water retention without sacrificing good aeration. It encourages the development of strong, healthy root systems for maximum stem, flower, and foliage growth.

    Sunshine Advanced Ultra Coir has the dual benefits of coir (coconut fiber) and peat moss to hold water and nutrients for optimal plant growth. The perlite provides excellent drainage, resulting in a mix that is most suitable for growing conditions where plants need to be watered more frequently. Our organic nutrient package gives a supplemental charge to help plants get started, and our endomycorrhizal blend enhances the ability of plants to access the nutrients in the root zone.

    This formula was modeled after our professional coir-based mixes used in greenhouses and nurseries on a wide variety of ornamental and agricultural crops. We’ve trialed the mix in our own greenhouses until we developed a formula that maintains high water retention while still providing excellent air porosity and nutrient availability. In addition, using our in house lab, we examined the roots for mycorrhizal colonization to determine that Sunshine Advanced Ultra Coir would optimize the effectiveness of mycorrhizae on root growth. Ongoing testing in our trial greenhouses ensures that Sunshine Advanced Ultra Coir will continue to provide the maximum results you expect from all Sunshine products.

    Sunshine Advanced Ultra Coir is designed to provide a perfect background to your own fertility program because it is essentially inert when you receive it. An organic fertilizer is included to give a background boost to your seedlings or transplants. You should start your own feeding program within 7 days after planting or seedling emergence. Mycorrhizae require low phosphorus fertilizer for optimal growth. During the plant’s active foliar growth stage, it is important to remember to use fertilizer with high nitrogen and low phosphorus.

    Using endomycorrhizae means you only get the mycorrhizal species that actually work with garden, foliage, and vegetable plants. Other growing mixes offer ectomycorrhizae as part of their mycorrhizal blend – but ectomycorrhizae only work for 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 multi-species blend of endomycorrhizae ensures that your plants will derive the maximum benefit from the same fungi that colonize their roots in nature.


    1. How is Sunshine Advanced Mix Ultra Coir different from other competitive coir products?
    Sunshine Advanced Ultra Coir contains washed coir, Canadian sphagnum peat moss and coarse perlite. Coir has unique properties of high aeration coupled with excellent water retention and is frequently used in peat mixes to aid in rapid rewetting of the mix. Many other coir products on the market are only coir and may need to be blended with other ingredients for optimal performance. In addition, Sunshine Advanced Ultra Coir is natural and organic.

    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 and enhance uptake by the plants. It is estimated that 90% of the world’s plants are dependent on mycorrhizae in their native habitats.

    3. Why should I use mycorrhizae in my growing mix?
    The same benefits of using mycorrhizae 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 continue to grow along with the roots, seeking nutrients to provide to the plant.

    4. Why does Sunshine Advanced Ultra Coir contain an organic fertilizer?
    Our custom designed organic fertilizer contains both feather meal and sulfate of potash and gives your plants a base fertility level. We kept the fertilizer at a low level so you would be able to customize your fertilizer program for the needs of your plants. 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 are growing along with your plant, remember to 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, such as 20-9-20.

    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. Hal

      So during flowering, when phosphor is normally set higher (like 10 30 10) will the additional organic feet in ultra coir caused burning at that level? Should it on be raised to 10 20 10?

    2. Sunshine Advanced

      Hi Hal,

      We recommend a low phosphorus fertilizer with a middle number lower than 10, such as 20-9-20, or for lower nitrogen something like 1-4-5.
      Phosphorus (P2O5) is necessary for the development of roots, and as plants mature phosphorus moves into the flower bud and then into the fruit (seed). Adding more P does not necessarily mean bigger and more flowers and fruit! In fact, we recommend a low percentage of phosphorus since the mycorrhizae in the Sunshine Advanced mixes do their best work at low P levels, facilitating better root nutrient and water uptake and thereby providing the adequate amount of P for plant flowering.

      Please see our ‘Tech Talk’ on Sunshine Advanced Ultra Coir. There is a lot of information there that may answer some of your questions.

      The starter nutrients added to Ultra Coir are at a low dosage and will not cause burning of plant roots in combination with your fertilizer program, which you can start after 7 days post planting. We hope this helps!

    3. Troy

      I’ve read that using fertilizers that contain calcium carbonate in coco coir based potting mixes should be avoided. Apparently the properties of coco coir bind the carbonates and they precipitate into salts? These salts build up in the medium/coco and cause nutrient lock out issues. Should I used coco specific nutrients without calcium carbonate in them? Is there a way to flush the built up salts out to keep them from building up? Thanks.

    4. Sunshine Advanced

      Hi Troy,
      No fertilizers contain calcium carbonate, though the potential for fertilizers to increase pH or decrease pH is sometimes expressed in ‘Calcium Carbonate equivalents.’ Just remember that over-fertilizing with any fertilizer in any mix (not just coir based mixes) can lead to salt buildup over time, if too much is used.
      Our coir-based mixes, such as Sunshine Advanced Ultra Coir, are triple rinsed with water to leach out any salts. If your plants are on a fertilization program, just be sure not to over-fertilize, and water your pots until free-flowing water drains out of the bottom. Happy growing! Shawnee

    5. Cameron

      Hello, my zip code is 91016. Do you know where I can find the nearest place to pick up
      bags of Sunshine Advanced Ultra Coir 2.0 714782?

      Thank you,


    6. Sunshine Advanced

      Hi Cameron,

      Just check out our store finder! Plug in your zip code and you will see that there are lots of stores that carry SSA in your area. Call to determine specific availability as it will vary.

      Happy growing!

      SSA Team

    7. Sunshine Advanced

      Hi Jay,

      No. Our Sunshine Advanced Ultra Coir does not need to be rinsed or pH corrected. It is actually a mix of coir, peat and perlite. Our coir source rinses the coir with pure water to get rid of salts. When we mix the ingredients, we add the exact amount of lime to bring the pH to a range of 6.0 – 7.0.

      Happy growing!


    8. Shawn

      Are there any real benefits to using your coir blend vs say a sunshine #4 blended 50/50 with additional perlite for indoor container gardening? We grow in a high co2 environment with high feed ppm numbers, with zero runoff.

    9. Sunshine Advanced

      There are a couple of factors that need to be considered in your choice of media. First of all, when comparing Sunshine Advanced Ultra Coir to Sunshine Advanced Mix #4, The Ultra Coir has about 50% coir in it plus peat and perlite. Although Coir may hold water and at the same time have more pore space for your zero runoff, the salts (EC) may run higher with a coir product rather than a product that has more peat, like the Sunshine Advanced Mix #4. Therefore, from this standpoint, it would be best to use the Sunshine Advanced Mix #4 and add some perlite to it, to bring it up to a 50/50 mix (there is already a good bit of perlite in this mix, about 35 – 40 %).
      The other factors that need to be considered are the EC’s for your fertilizer, how often you are fertilizing. and what kind of water you are using. The water should be RO or distilled with a neutral pH. If the fertilizer is high in ppm and salts, and there is no runoff, you need to watch for burning. Also, there is a plateau for a high CO2 environment where the growth push levels off; you might have already researched to find out what levels you need for optimum results.