You can mix succulents with other plants, but success depends on aligning the biological needs of all the plants involved. Succulents are defined by their ability to store water in their leaves, stems, or roots, an adaptation for survival in arid environments. This water-storing capacity means they thrive under specific conditions that differ significantly from most common garden or houseplants. Creating a mixed container or garden bed requires careful selection and a unified care strategy to avoid damaging the succulents or sacrificing the companion plants. The key is to find plants that share the succulent’s preference for dry feet and low humidity.
The Fundamental Conflict: Water and Soil Needs
The primary challenge in mixing succulents with other plants stems from a fundamental conflict in their requirements for water and soil composition. Succulents have specialized, often shallow, root systems that are highly efficient at absorbing water quickly before the soil dries out. They are extremely susceptible to root rot, which occurs when their roots sit in moist soil for too long, essentially suffocating the plant.
Most traditional potting soils are designed to retain moisture and nutrients for plants with different needs, making them unsuitable for succulents. This organic-rich soil traps water and inhibits the necessary gas exchange around the roots, creating a perfect environment for fungal pathogens. In contrast, plants that rely on frequent watering will quickly dehydrate and fail when planted in the fast-draining medium succulents require.
The specialized nature of succulent roots means they prefer a gritty, fast-draining medium that mimics their native rocky, sandy habitats. This soil allows water to pass through rapidly, ensuring the roots dry out quickly after watering, which is necessary for their survival. Therefore, any companion plant must be able to tolerate and thrive in this dry, lean environment.
Criteria for Selecting Compatible Companion Plants
Selecting compatible companion plants relies entirely on matching their tolerance for drought, low nutrients, and fast-draining soil. Compatibility is determined by shared water needs, not by visual appeal or growth habit. The most successful pairings involve plants that are also native to arid or Mediterranean climates.
Look for non-succulent plants that are classified as highly drought-tolerant and can survive in poor, lean soil. These plants often possess water-saving adaptations, such as silvery or fuzzy leaves that reflect sunlight and reduce water loss through transpiration. Plants with similar growth rates are also beneficial to prevent one species from quickly overshadowing or outcompeting the others.
Several non-succulent varieties meet these requirements and serve as excellent companions:
- Certain Mediterranean herbs, like lavender (Lavandula) and thyme, thrive in the same well-drained conditions as succulents.
- The foxtail fern (Asparagus densiflorus ‘Meyers’) has drought-tolerant rhizomatous roots.
- Annual geraniums (Pelargonium) are surprisingly drought-resistant.
- Ornamental grasses such as blue fescue (Festuca glauca) or yarrow (Achillea millefolium) offer contrasting texture and color while tolerating dry conditions.
Achieving Harmony: Planting and Care Strategies for Mixed Containers
Successful mixed containers depend on the physical structure and a modified maintenance routine that satisfies the shared low-water needs. The container itself must have drainage holes to allow excess water to escape immediately; using porous materials like unglazed terracotta also helps wick away moisture. This immediate and complete drainage is necessary to prevent the soil from becoming saturated for extended periods, a condition detrimental to the succulents.
The soil mix should be customized to enhance drainage far beyond standard potting soil. A successful blend typically involves a high ratio of inorganic grit to organic material. A good starting point is a mixture that is roughly one-third organic material, such as potting soil or coconut coir, and two-thirds mineral material. Mineral amendments like coarse sand, perlite, pumice, or fine gravel are incorporated to improve aeration and facilitate rapid water flow.
Watering technique must strictly follow the “soak and dry” method. This involves thoroughly saturating the soil until water runs out of the drainage holes and then allowing the entire soil volume to dry out completely before watering again. For mixed containers, checking the soil moisture a few inches down determines the timing, ensuring the roots of all plants are ready for the next deep watering. If some companion plants show signs of thirst before the succulents, localized, targeted watering can be used to meet their needs without soaking the entire container.