From our perspective, the single most critical factor in our soil home is the ability to avoid "wet feet." Our roots are highly susceptible to rot if left sitting in saturated, poorly drained soil. A dense, water-retentive mix is a death sentence for us. Therefore, the ideal medium must be porous and free-draining, allowing excess water to flow out of the pot's drainage holes quickly after watering. This ensures our roots have access to both the water they need and the oxygen essential for respiration and healthy growth.
We thrive in a lightweight, well-aerated potting mix that strikes a perfect balance between moisture retention and drainage. A high-quality, sterile commercial potting mix designed for container gardening is an excellent base. To this, you should add amendments that further improve the structure. A combination we find particularly agreeable is two parts potting mix to one part perlite and one part coarse horticultural sand or small bark chips. The perlite creates vital air pockets, while the sand or bark grit ensures the mix remains loose and does not compact over time, safeguarding our root zone.
While we are not excessively heavy feeders, we do appreciate a modestly fertile environment to support our prolific blooming. The potting mix should contain a small amount of a balanced, slow-release fertilizer to provide steady nutrients throughout our main growing season. More importantly, the soil pH is crucial. We prefer a neutral to slightly acidic soil pH, ideally ranging from 5.5 to 6.5. This pH range allows our roots to most effectively uptake the available nutrients, particularly iron, which is vital for maintaining our vibrant green foliage and supporting flower production.
Please avoid using garden soil or topsoil in our containers. These materials are far too dense for pot culture, leading to severe compaction, poor drainage, and a high risk of introducing soil-borne pests and diseases. Furthermore, steer clear of potting mixes that feel heavy, muddy, or are marketed for moisture-loving plants. Soils that retain too much water will suffocate our roots and ultimately lead to plant failure. A good mix should feel light and fluffy in your hands.
The choice of pot is an extension of our soil environment. Regardless of the material—plastic, terracotta, or ceramic—the container must have adequate drainage holes. Terracotta pots are beneficial as they are porous and allow the soil to dry out more evenly from the sides, reducing the risk of overwatering. The size of the pot should be appropriate for our root ball, with a little room to grow; too large a pot will hold excess soil that stays wet for too long, creating a hazardous environment for our root system.
