Soil Additives

87 products

  • CHARCOAL - FERT-LOME 1.5 LB (750G)

    Lambert CHARCOAL - FERT-LOME 1.5 LB (750G)

    Out of stock, 1-3 weeks

    CHARCOAL - FERT-LOME 1.5 LB (750G)

    Out of stock, 1-3 weeks

    $10.99

  • Hoffman's Garden Gypsum - 5LB

    Hoffman Hoffman's Garden Gypsum - 5LB

    Out of stock, 1-3 weeks

    Out of stock, 1-3 weeks

    $8.99

  • Sale -7% Lambert Horticultural Perlite 8 Dry Qt

    Lambert Lambert Horticultural Perlite 8 Dry Qt

    Out of stock, 1-3 weeks

    Lambert Horticultural Perlite 8 Dry Qt

    Out of stock, 1-3 weeks

    $13.99 $12.99

  • Black Gold® Peat Moss Plus - 8qt

    Black Gold Black Gold® Peat Moss Plus - 8qt

    Out of stock, 1-3 weeks

     Canadian Sphagnum peat moss plus an added organic wetting agent. Particularly suited to acid-loving plants and can slightly lower the pH of more alkaline soils. This product is OMRI® Listed 

    Out of stock, 1-3 weeks

    $8.49

  • Mosser Lee® Long Fibered Sphagnum Moss - 432cu in

    Mosser Lee Mosser Lee® Long Fibered Sphagnum Moss - 432cu in

    Out of stock, 1-3 weeks

    Long fibered, fluffy and clean. Absorbs and retains up to twenty times its weight in water. Use for soilless gardening, transplanting, mulch and hanging basket filler. For soil mixes, it offers excellent root aeration. Also used for rooting bulbs, cuttings and swamp gardens. Long-Fibered Sphagnum Moss is not peat moss, but rather a perennial plant that grows wild in the Central Wisconsin sphagnum bogs. Mosser Lee's sphagnum is a renewable resource growing back in the same bogs every 5-7 years, so using Mosser Lee's long-fibered sphagnum does not destroy our precious wet lands.

    Out of stock, 1-3 weeks

    $10.99

  • Sol Soils Chunky Perlite™ - 64oz (2qt)

    Sol Soils Sol Soils Chunky Perlite™ - 64oz (2qt)

    Out of stock, 1-3 weeks

     Chunky Perlite is a large and super lightweight, naturally occurring volcanic glass. When heated to the appropriate temperature during processing, it expands like popcorn. As a soil amendment perlite keeps mixes lighter and allows water to flow through. Popular with many leafy plants and orchids especially. 

    Out of stock, 1-3 weeks

    $14.99

  • Build A Soil Certified Organic Straw Mulch (BOX) - 2cu ft

    Build-A-Soil Build A Soil Certified Organic Straw Mulch (BOX) - 2cu ft

    Out of stock, 1-3 weeks

      Looking for mulch but don't have a farm in your backyard? We now have the Organic Certification for this straw!! We have access to an abundance of straw and are happy to ship you some for your small garden. Larger gardens will benefit from sourcing locally. This barley straw is CERTIFIED ORGANIC and comes from a local farm.  We get MONSTER bales by the full truckload and then store it on pallets under hay tarps to ensure the cleanest organic straw for your garden.  Looking for something that has NO seeds? Check out our Blue Oyster Mushroom Straw Logs. They are made on an organic mushroom farm and pre-sterilized before they grow mushrooms on them.  Useful Info 1 Cubic Foot of straw doesn't weigh much but will easily mulch 6-12 plants depending on the depth of mulch and the size of the container. The straw is compressed when baled and we do not fluff it up before packaging. So 1 bag will hold more than you think. Approximate measurements: 1/2 Cubic Foot Bag - Good for 5-10 Plants 1 Cubic Foot Bag - Good for 6-12 Plants 2 Cubic Foot Box - This is a 30x15x15 box is uncompressed barley straw from our compressed bales. The weight of the boxes may vary, but we will always get them as full as possible! Free Bonus - This straw will have seeds in it still and you will have volunteer "Living Mulch" in your containers. This grass will move moisture around in your soil container and provide additional root exudates to feed the microlife. If you have been waiting to mulch until you get a round to it.... Well that day is today. Add a box of Organic Straw to your shopping cart and take your garden to the next level. How To Use Top dress your containers for a sweet straw mulch layer. I often put my straw into a tub or bucket and moisten it so that it's less dusty and clean and easy to apply as mulch. You could even presoak your straw in Yah-Whey or something microbial to help kick start the break down. 

    Out of stock, 1-3 weeks

    $60.00

  • Sale -17% Organic Inoculated Biochar - 64oz

    Foop Organic Inoculated Biochar - 64oz

    Out of stock, 1-3 weeks

    Organic Inoculated Biochar helps plants, trees, and shrubs get the most out of soil. Biochar is like a sponge: it will absorb anything it comes into contact with – and one small handful has the surface area of a football field. This makes biochar a perfect medium to house nutrients, moisture, and microbes – the three building blocks of plant life. CONTAINS MILLIONS OF SOIL-ENRICHING MICROORGANISMS: Provides a perfect habitat for soil-enriching microbes, and comes preloaded with billions of them to kick-start the soil microbiology of any lawn, field, or container -- improving soil health & fertility HELPS PLANTS, TREES, AND SHRUBS GET THE MOST OUT OF SOIL: Absorbs and retains excess nutrients and moisture and makes both available when plants need them most -- allowing plants to uptake nutrients more efficiently ORGANIC AND MADE IN THE USA: Ensuring quality and safety standards are met and guaranteed not to contain any harmful chemicals SUSTAINABLE AND SAFE: Sustainably sourced from pine industry waste; safe to use; no dusty particles, no PPE required. MIXING INSTRUCTIONS: Combine entire contents of this bag with one cubic foot of soil.

    Out of stock, 1-3 weeks

    $29.99 $24.99

  • PVP Industries® Horticultural Grade Vermiculite - 4cu ft - Super Coarse - OMRI Listed®

    PVP Industries PVP Industries® Horticultural Grade Vermiculite - 4cu ft - Super Coarse - OMRI Listed®

    Out of stock, 1-3 weeks

     PVP Industries® Horticultural Grade Vermiculite is a permanent, clean, odorless, sterile, and pH neutral medium that mixes easily with soil, peat, composted bark, fertilizers, pesticides, and herbicides to support faster root growth and reliable anchorage for young plants. Its natural wicking properties help attract and hold essential nutrients such as ammonium, potassium, calcium, and magnesium while maintaining aeration and moisture retention for consistent plant development. Vermiculite can absorb more than three times its volume in water, making it suitable for passive hydroponic setups, seed germination, and cutting propagation. Common Uses: Super Coarse Vermiculite is commonly used for hydroponics, high value crop production, high porosity soil mixes, packaging filler, adsorbent & cushion, squarefoot gardening, raised bed gardening, etc. Chemical Analysis Silicon dioxide (SiO₂) 38-46% Aluminum oxide (Al₂O₃) 10-16% Magnesium oxide (MgO) 16-35% Calcium oxide (CaO) 1-5% Potassium oxide (K₂O) 1-6% Iron oxide (Fe₂O₃) 6-13% Titanium dioxide (TiO₂) 1-3% Water (H₂O) 8-16% Other 0.2-1.2% Properties Moisture Content: < 0.5% pH Range: 6.5-7.5 Bulk Density: 4-7lbs per cu ft

    Out of stock, 1-3 weeks

    $46.99

  • PVP Industries® Super Coarse Horticultural Perlite - 4cu ft - Super Coarse

    PVP Industries PVP Industries® Super Coarse Horticultural Perlite - 4cu ft - Super Coarse

    Out of stock, 1-3 weeks

     Excellent as a substrate for hydroponics. Super coarse grade expanded perlite is clean, sterile, pH neutral, non-flammable and nontoxic. Increases aeration and drainage of growing media and helps anchor roots of young plants. 

    Out of stock, 1-3 weeks

    $38.95

  • Build A Soil Pumice - 7 Quart (1/4"-3/8")

    Build-A-Soil Build A Soil Pumice - 7 Quart (1/4"-3/8")

    Out of stock, 1-3 weeks

     Description BuildASoil Pumice Horticultural Grade: Very porous for holding air. Approximately 50% will float and 50% will sink which is ideal for soil building. Some pumice mines are also full of obsidian which is what perlite is made from and 100% will sink and not add the same air holding properties. When making potting soil, insist on horticultural grade. Last Longer Than Perlite & Has More Minerals!  This is the BuildASoil Way! Pumice makes soil that lasts forever and is more sustainable than throwing your potting soil away after each use. Our 3/8" x 1/4" Pumice is perfect for potting soil. Optimizes drainage Excellent for Living Organic Soil and also for Bonsai Retains and evenly distributes moisture and nutrients Promotes strong root growth Improves root aeration Low Heavy Metals - Used in beauty products also Does not contain clay or organic material (i.e. montmorillonite, illite, kaolinite) Minimizes root diseases Clean from disease or weed seeds and environmentally friendly What Makes BuildASoil Pumice Unique? Premium Quality and Clean Sourcing BuildASoil pumice is known for its exceptional quality and consistency. Sourced from clean, natural deposits, our pumice undergoes rigorous quality control processes to ensure it meets the highest standards. This meticulous sourcing results in a product that is pure, effective, and reliable for a variety of gardening and horticultural needs. Versatility for Various Uses Our pumice is incredibly versatile and perfect for a wide range of applications. Whether you're cultivating living organic soil, enhancing houseplants, creating bonsai and cactus mixes, or blending succulent mixes, BuildASoil pumice provides the ideal medium. Additionally, it serves as an excellent mulch, helping retain moisture while preventing soil compaction. Sustainability and Environmental Benefits Pumice from BuildASoil is more sustainably produced compared to alternatives like perlite. By choosing pumice, you're opting for an environmentally friendly solution that supports sustainable gardening practices. Pumice is a naturally occurring volcanic rock that requires minimal processing, reducing its environmental footprint and ensuring a sustainable choice for eco-conscious gardeners. Free Shipping and Convenient Delivery We understand the importance of convenience and accessibility for our customers. That's why we offer free shipping on all our pumice products, ensuring that you receive your order quickly and efficiently right at your doorstep. Our reliable shipping process is designed to provide you with hassle-free delivery, making it easier than ever to get the gardening supplies you need. Outstanding Customer Satisfaction Our commitment to quality and customer satisfaction is reflected in our over 200 five-star reviews. Customers consistently praise BuildASoil pumice for its excellent quality, consistency, and the benefits it brings to their plants and gardens. The positive feedback from our satisfied customers is a testament to the superior performance and reliability of our products. Expertly Recommended for Living Organic Soil BuildASoil pumice is highly recommended by experts for use in living organic soil. Its unique properties enhance soil aeration, improve drainage, and support healthy root development, making it a preferred choice among professional gardeners and hobbyists alike. By incorporating pumice into your soil mix, you can create an optimal growing environment that promotes vigorous plant growth. Perfect for Specialized Plant Mixes Our pumice is a crucial component in specialized plant mixes such as bonsai soil, cactus mix, and succulent blends. Its lightweight, porous structure helps prevent root rot and promotes proper drainage, essential for the health and vitality of these plants. Gardeners trust BuildASoil pumice to provide the ideal growing conditions for their most cherished plants. Proven Replacement for Perlite Pumice is an excellent replacement for perlite, offering similar benefits with additional advantages. Unlike perlite, which is often associated with dust and environmental concerns, pumice is a cleaner, more sustainable alternative. It provides superior aeration and drainage, making it a valuable addition to any soil mix while minimizing environmental impact.

    Out of stock, 1-3 weeks

    $31.00

  • Espoma® Horticultural Charcoal - 4qt

    Espoma Espoma® Horticultural Charcoal - 4qt

    Out of stock, 1-3 weeks

     Naturally detoxifies, cleanses, and absorbs excess water from its porous pieces. Acts as a filter and also retains moisture while removing excess moisture for your plants. 

    Out of stock, 1-3 weeks

    $15.99

  • Espoma® Organic® Peat Moss - 8qt

    Espoma Espoma® Organic® Peat Moss - 8qt

    Out of stock, 1-3 weeks

     All natural sphagnum peat moss. Improves aeration and moisture retention. Part of a complete line of potting mixes and soil amendments that can be used for organic gardening. Each mix contains a rich blend of only the finest natural ingredients. No synthetic plant foods or chemicals are used. All natural and organic, premium quality blends. 

    Out of stock, 1-3 weeks

    $9.99

  • Harvest Hero 3-in-1 Enhanced Perlite Mix - 8QT

    Harvest Hero Harvest Hero 3-in-1 Enhanced Perlite Mix - 8QT

    Out of stock, 1-3 weeks

     Perlite with unsurpassed texture, porosity and high cation exchange capacity, creates a perfect growing environment. A breakthrough, patent-pending, soil amendment comprised of perlite, diatomaceous earth, and essential nutrients for your growing media needs. This mix has been designed by Harvest Hero’s team of engineers, operations personnel, and agronomists to improve soil structure for nutrition which promotes bigger plants and bigger yields. Meet your plants’ needs throughout the first critical 6 weeks of growth by improving soil quality, providing plant nutrients, and amending soil properties to make it easier for the plant to absorb and translocate essential plant nutrients to the root system. Perlite: 71.40% - Natural Diatomaceous Earth (17.10%) - Fertilizer: 5.70% - Proprietary Aqueous solution: 5.00% - Essential Nutrients (5.70% – 0 – 10 – 10) - Other ingredients: 0.80%. 28% Increase in Flower Bud Dry Weight - 16% Increase in CBD Yield - 22% Increase in Plant Diameter - 8% Increase in Plant Height - 12% Increase in Nitrogen Accumulation - 35% Increase in Phosphorus Accumulation - 21% Increase in Potassium Accumulation. Developed by Dicalite which was founded in 1949. You can search You Tube to see many videos explaining the many benefits of Harvest Hero.  

    Out of stock, 1-3 weeks

    $16.99

  • Colorado Worm Company Vermicompost - 1/2 cu ft

    Build-A-Soil Colorado Worm Company Vermicompost - 1/2 cu ft

    Out of stock, 1-3 weeks

    Application methods and rates: 🌼 Top-dress your flowerpots or raised beds with a generous two-inch layer every two weeks to one month during both veg and flower stages. For an extra phosphorus boost, aerate water and add our castings at a rate of 1:10 to water, brew for no more than 24 hours, and apply directly to the root zone for immediate results. 🌍 Eco-Friendly Production: Our operation boasts a minimal carbon footprint, utilizing only a modest tractor while maintaining a closed-loop system with our hardworking worms. 🚜 📢 YouTube Testimonial: "These were some of the finest worm castings that I have ever used. You definitely hit it out of the park with the superior quality, microbial life, and nutrient density." - Alex 🌟 Ready to elevate your gardening game? Order now and let us help make your green thumb even greener! Colorado Worm Company AKA "COWOCO" 1 Cubic Foot = Approximately 40 lbs 1/2 Cubic Foot = Approximately 20 lbs 2 Gallon Bag = Approximately 10 lbs 1 Cubic Yard = Approximately 1000 lbs

    Out of stock, 1-3 weeks

    $64.00

  • Coast of Maine® Bar Harbor Blend™ Organic & Natural Potting Soil - 16qt - OMRI Listed®

    Coast of Maine Coast of Maine® Bar Harbor Blend™ Organic & Natural Potting Soil - 16qt - OMRI Listed®

    Out of stock, 1-3 weeks

     This great all-purpose potting soil is made with natural and organic ingredients such as lobster, kelp, compost, perlite and sphagnum peat. It is designed for potting indoor and outdoor container plants. Water and fertilize less with this nutrient rich, compost-based potting soil. OMRI Listed®. 

    Out of stock, 1-3 weeks

    $17.69

  • SunBulb® Better-Gro® Orchid Bark - 8qt

    SunBulb SunBulb® Better-Gro® Orchid Bark - 8qt

    Out of stock, 1-3 weeks

     Premium, multi-purpose potting medium for all epiphytic orchids, as well as bromeliads, ferns and a wide variety of other ornamentals. Perfect for potting, re-potting, or spot refilling. It is also a great base for creating custom mixes. Combination of specifically sized and graded western fir bark. 

    Out of stock, 1-3 weeks

    $10.59

  • Espoma® Organic® Perlite - 8qt

    Espoma Espoma® Organic® Perlite - 8qt

    Out of stock, 1-3 weeks

     All natural, 100% pure product. Loosens soils and prevents compaction. Part of a complete line of potting mixes and soil amendments that can be used for organic gardening. Each mix contains a rich blend of only the finest natural ingredients. No synthetic plant foods or chemicals are used. All natural and organic, premium quality blends. 

    Out of stock, 1-3 weeks

    $12.49

  • PVP Industries® Medium Horticultural Perlite - 4cu ft - Medium

    PVP Industries PVP Industries® Medium Horticultural Perlite - 4cu ft - Medium

    Out of stock, 1-3 weeks

     Used primarily for plugs, small cells, hanging baskets and gardening. Horticultural perlite is clean, sterile, pH neutral, non-flammable, odorless, non-toxic and neither decays nor shrinks even pests such as insects and fungi can't destroy it. 

    Out of stock, 1-3 weeks

    $31.95

  • Sale -30% PRO MIX HP with Mycorrhizae - 3.8 cu ft

    Pro-Mix PRO MIX HP with Mycorrhizae - 3.8 cu ft

    Out of stock, 1-3 weeks

     PRO-MIX HP Mycorrhizae is a high porosity peat-based growing medium, ideal for water sensitive crops, rooting cutting and/or low-light growing conditions with mycorrhizae. Features: *High perlite content, peat-perlite based growing medium *Low water retention *Designed for water sensitive crops *Ideal for cultural conditions with low-light and excess moisture/humidity Benefits: *Dries out more frequently than general purpose, peat-based mixes *Well suited for low-light growing conditions and high humidity *Less difficult to overwater crops *Reduces incidence of water related problems (root diseases, algae and fungus gnats) *Holds less water for improved leaching of fertilizer salts during crop cycle 

    Out of stock, 1-3 weeks

    $75.95 $52.99

  • Sale -27% PRO MIX HPCC Mycorrhizae - 3.8 cu ft

    Pro-Mix PRO MIX HPCC Mycorrhizae - 3.8 cu ft

    Out of stock, 1-3 weeks

    PRO-MIX HP-CC MYCORRHIZAE is a lightweight, high-porosity peat-based growing medium that contains chunk coir. It ensures optimum growth, especially when high air capacity and extra drainage are required. It is ideal for water-sensitive crops, rooting cuttings and/or low-light growing conditions that contains a beneficial mycorrhizal inoculum (Glomus intraradices). These microscopic fungi attach to and colonize the root systems working in symbiosis with plants. It benefits the plant by increasing water and nutrients acquisition (especially Phosphorus, Copper and Zinc). This symbiotic relationship between fungi and plant, results in an overall improved plant growth PRO-MIX HP-CC MYCORRHIZAE is suitable for a wide variety of horticultural plants.

    Out of stock, 1-3 weeks

    $74.95 $54.99

  • Sale -29% Wiggle Worm Soil Builder Earth Worm Castings 30 lb

    Wiggle Worm Wiggle Worm Soil Builder Earth Worm Castings 30 lb

    Out of stock, 1-3 weeks

    Wiggle Worm Soil Builder PURE Worm Castings are an organic fertilizer that, because they are pure, when a small handful is added during transplant you could see plants that are 3 times larger and more fruitful. This makes it extremely cost effective.Wiggle Worm Soil Builder has been on the market for 4 decades, has the BEST price, GREAT margins and LOYAL repeat customers.Wiggle Worm Soil Builder is OMRI and CDFA certified and a registered organic fertilizer.

    Out of stock, 1-3 weeks

    $34.99 $24.99

  • Sale -27% PRO MIX HP with Mycorrhizae 2.8 cu ft

    Pro-Mix PRO MIX HP with Mycorrhizae 2.8 cu ft

    Out of stock, 1-3 weeks

    PRO-MIX HP MYCORRHIZAE is a high porosity peat-based growing medium containing, beneficial mycorrhizal inoculum (Glomus intraradices). This formula ensures optimum growth, especially when high air capacity and extra drainage are required. It is ideal for water sensitive crops, rooting cutting and/or low-light growing conditions.Ingredients:Canadian Sphagnum peat moss (65-75% by volume)Perlite - horticultural gradeDolomitic and Calcitic limestone (pH adjuster)Wetting AgentMycorrhizae - endomycorrhizal fungi (Glomus intraradices)

    Out of stock, 1-3 weeks

    $39.95 $28.99

  • Sale -31% PRO MIX BX with Mycorrhizae - 3.8 cu ft (White)

    Pro-Mix PRO MIX BX with Mycorrhizae - 3.8 cu ft (White)

    Out of stock, 1-3 weeks

     High Performance Growing Media for Professionals. The General Purpose growing medium PRO-MIX BX is a "General Purpose" peat-based growing medium used for the cultivation of wide variety of plant species. It is lightweight, uniform and blended to the highest degree of consistency to provide the necessary condition for establishing plant growth. Components: *Canadian Sphagnum peat moss(65-75% by vol.) *Perlite *Vermiculite *Macronutrients and Micronutrients *Dolomitic and calcitic limestone (pH adjuster) *Wetting agent Applications: * Bedding trays * Hanging baskets * Potted flowering plants * Propagation of cuttings * Foliage * Dish gardens * Herbs * Perennials * Vegetables * Cut flower beds * Interior design 

    Out of stock, 1-3 weeks

    $71.95 $49.99


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