Some ornamentals don’t like rich compost
At Deep Roots Project, our mission is to empower gardeners to grow vibrant, healthy edible plants using 100% microbe-rich and nutrient-rich compost. While many know us for supporting food gardening, our compost is equally transformative for many ornamental gardens. Whether you’re cultivating colorful flowers, native plants, or decorative plants and shrubs, incorporating our premium compost can help you achieve lush, thriving landscapes.
Use compost for food & most ornamentals
Ornamental plants, like edibles, depend on healthy soil to flourish. Our compost:
• Improves soil structure, making it easier for roots to penetrate and access nutrients.
• Boosts water retention, reducing the need for frequent watering.
• Increases disease resistance, thanks to beneficial microbes that suppress pathogens.
• Provides a slow, steady release of essential nutrients, creating ideal conditions for blooms and foliage.
Ornamentals that thrive with our compost
• Perennials: Coneflowers, black-eyed Susans, daylilies, hostas.
• Annuals: Petunias, marigolds, impatiens, zinnias.
• Bulbs: Tulips, daffodils, hyacinths.
• Native Plants: Butterfly weed, prairie dropseed, purple prairie clover.
• Shrubs: Hydrangeas, lilacs, viburnums.
• Flowering Vines: Clematis, honeysuckle.
• Ground Covers: Creeping thyme, ajuga, vinca.
Some need low fertility compost
Some ornamental plants prefer low-fertility soil conditions to mimic their native habitats. A more detailed list of low-fertility soil ornamentals is below.
Use compost sparingly or avoid it altogether for these plants:
• Herbs from Arid Climates: Lavender, rosemary, thyme.
• Succulents: Sedum, echeveria, jade plant.
• Carnivorous Plants: Venus flytraps, pitcher plants (which thrive in nutrient-poor, acidic soils).
• Wildflowers for Lean Soils: Poppies, some varieties of cosmos.
How to use our compost on ornamentals
For best results:
• Top-dress beds with a 1-2 inch layer of compost in spring and fall.
• Mix into planting holes when setting new plants to encourage strong root establishment.
• Apply as mulch around shrubs and perennials to suppress weeds and retain moisture.
A Garden That Gives Back
By using our compost on your ornamental plants, you’re not just enhancing your garden’s beauty. You’re also fostering a healthier ecosystem, improving soil health, and supporting pollinators like bees and butterflies.
Whether you’re growing roses or prairie natives, Deep Roots Project compost provides the foundation for a garden that flourishes. Visit our website or contact us to learn more about how our compost can bring life to your ornamental garden!
Gardening Tip: If you’re unsure whether a plant will thrive with nutrient-rich compost, start by applying it to a small area and observe how your plant responds. Happy gardening!
Plants that prefer low-fertility soils - expanded list
Certain plants thrive in nutrient-poor, well-drained soils and may not perform well with our rich, microbe-packed compost. Here’s a more comprehensive list of plants that prefer low-fertility soil conditions.
Herbs and shrubs from arid climates
• Lavender (Lavandula spp.)
• Rosemary (Salvia rosmarinus)
• Thyme (Thymus spp.)
• Sage (Salvia spp., especially ornamental varieties)
• Santolina (Santolina chamaecyparissus, also called lavender cotton)
• Russian Sage (Perovskia atriplicifolia)
Succulents and drought-tolerant plants
• Sedum (Stonecrop varieties)
• Echeveria
• Jade Plant (Crassula ovata)
• Aloe Vera
• Cactus (Various species)
Wildflowers for low-fertility soils
Wildflowers often evolved in low-nutrient soils and can struggle with excessive fertility. Examples include:
• Poppies (Papaver spp.)
• Cosmos (Some varieties like Cosmos sulphureus)
• Coreopsis (Coreopsis lanceolata, aka tickseed)
• Gaillardia (Blanket flower)
• Butterfly Weed (Asclepias tuberosa)
• Yarrow (Achillea millefolium)
• Blue Flax (Linum perenne)
• Black-eyed Susan (Rudbeckia hirta, in naturally lean soils)
• Bachelor’s Button (Centaurea cyanus)
• Corncockle (Agrostemma githago)
• Dianthus (Cheddar pinks or maiden pinks)
• Wild Lupine (Lupinus perennis, adapted to sandy soils)
• Blazing Star (Liatris spicata)
Carnivorous plants
Carnivorous plants are adapted to nutrient-poor, acidic soils and rely on trapping insects for nutrition. Avoid compost for:
• Venus Flytrap (Dionaea muscipula)
• Pitcher Plants (Sarracenia spp.)
• Sundews (Drosera spp.)
• Butterworts (Pinguicula vulgaris)
Other plants that thrive in low-fertility soils
• Heaths and heathers (Erica and Calluna spp.)
• Rock garden plants (like Saxifraga and Armeria)
• Broom (Cytisus scoparius)
• Catmint (Nepeta spp.)
• Edelweiss (Leontopodium alpinum)
• Sea Thrift (Armeria maritima)
• Ornamental grasses (Such as blue fescue and little bluestem)
General rule of thumb
Plants native to dry, rocky, or sandy regions often prefer lean soil conditions. Over-fertilizing or using nutrient-rich compost can result in excessive foliage growth at the expense of flowers, leggy or weakened stems, or even root rot.
For gardeners wanting to grow these species, amending soil lightly with sand, perlite, or grit instead of compost is often the better approach.
Adapting our compost to low-fertility soil
Here are some practical ways to adapt Deep Roots Project’s high-fertility compost to create a lower-fertility soil:
1. Mix with leaf mulch (1:1 Ratio) Leaf mulch, made from shredded or decomposing leaves, is low in nutrients but rich in organic carbon. Mixing compost with leaf mulch:
• Dilutes the nutrient density.
• Adds texture and drainage.
• Mimics natural forest soil, ideal for wildflowers and woodland ornamentals.
2. Mix with sand (1:1 ratio) Sand is an inert material that provides excellent drainage and aeration. Combining compost with sand:
• Reduces nutrient levels.
• Creates soil structure for succulents, herbs, and Mediterranean plants.
• Prevents water-logging for plants sensitive to wet roots.
• Use coarse builder’s sand, not play sand, to ensure proper drainage.
3. Mix with existing yard soil (1:1 ratio) Gardeners can create a custom soil blend by mixing compost with the natural soil in their yard:
• Balances the high fertility of compost with the lower-nutrient properties of native soil.
• Maintains a sense of "local" soil for native plants.
• Encourages a gradual increase in soil health while staying lean.
4. Mix with topsoil from a garden center (1:1 ratio) Topsoil is often a basic, minimally amended soil available at garden centers. Combining compost with topsoil:
• Provides a balanced medium with moderate fertility.
• Works well for general-purpose planting.
• Offers a cost-effective option for larger projects.
5. Add drit or dravel (Optional 1:1 or 1:2 ratio with compost) Grit or fine gravel is another way to dilute fertility and improve drainage:
• Ideal for alpine plants, succulents, and drought-tolerant species.
• Helps mimic rocky or sandy soil conditions.
• Prevents root rot in plants sensitive to excess water and nutrients.
6. Let compost age before mixing: Letting compost sit and age (e.g., in a corner of the garden) naturally reduces nutrient content as some nutrients leach out with rain:
• Combine aged compost with native soil or mulch.
• A great option for gardeners looking to “weaken” compost without additional materials.
7. Use smaller amounts of compost in the nix (e.g., 1:2 or 1:3 ratios) For plants particularly sensitive to nutrient-rich compost, use less compost:
• Mix 1 part compost with 2 or 3 parts sand, native soil, or other low-nutrient materials.
• Tailor the blend to suit specific plant requirements.
8. Incorporate sawdust or wood chips. Mixing compost with sawdust or finely shredded wood chips:
• Lowers fertility while adding organic carbon.
• Ideal for creating soil conditions that mimic forest edges or sandy woodlands.
• Works best with fully composted wood chips to avoid nitrogen lock-up.
9. Combine with peat moss or coconut coir. For a lightweight, low-fertility medium, mix compost with:
• Peat moss: Provides acidity and low nutrients, ideal for acid-loving plants.
• Coconut coir: Sustainable and similar to peat moss, with excellent water retention.
10. Layer instead of mixing. For plants that thrive in lean soils, gardeners can layer compost beneath a top layer of sand, mulch, or low-nutrient soil:
• Ensures roots can access nutrients gradually.
• Keeps the surface lean, mimicking natural conditions.
How to find more details
Get more details on plants not on our list from Google, books and by contacting the Chicago Botanic Garden Plant Information Service ((847) 835-0972 or plantinfo@chicagobotanic.org).You could also experiment with these methods based on your plants’ needs.
Questions, comments, suggestions? We’d love to hear from you! If you need a quick answer to a gardening question give us a call or send a text. We are here to solve your gardening problems. Please call OR text our Customer Service team at 708-655-5299 OR send an email to: support@deep-roots-project.org.
Happy Gardening!
By following the Deep Roots Project’s transformational gardening methods through the seasons, you will create a thriving, nutrient-rich garden that supports both your plants and the soil. See the full list of our Grow Your Own Food blog posts. Each post is assigned ”tags” which are under the post title.
Deep Roots Supports Gardeners
We provide our gardeners with the best products for success – like cedar raised beds, microbe-rich compost and microbe-rich worm castings. Check our online store. Always talk to our customer support team before placing your order online. If you need help or have a question contact us at support[at]deep-roots-project.org and 708-655-5299.
Deep Roots online store
See our online store for details about prices, ordering and delivery of raised beds, planter boxes, microbe-rich compost, worm castings, leaf mulch and more. We don’t sell traditional soil, since we use 100% compost as our growing medium. Our online store has 2 sections – (1) raised beds and planter boxes and (2) compost, worm castings, fertilizer.
Please contact our customer support team before placing an order online so we can assist you with the details and answer your gardening questions. You can pay by credit card on the store or by check.
(708) 655-5299 and support[at]deep-roots-project.org
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