From my perspective, the most critical element is water, but it must be just right. My roots are not fond of being constantly wet. If the soil is heavy, doesn't drain, or you water me too frequently, my roots will suffocate and begin to rot. I cannot uptake nutrients or water with damaged roots, so my growth above the soil will stall completely, and my leaves may turn yellow or brown. Conversely, if the soil becomes bone dry for extended periods, I become severely stressed. My small, shallow roots desiccate, and my growth halts as I enter survival mode, causing my leaves to become brittle and crispy. I need soil that allows water to pass through freely, leaving my roots moist but never sitting in a swamp.
I am a child of the Mediterranean sun. To photosynthesize and create the energy needed for robust growth, I require a tremendous amount of direct light. If you have placed me in a shady spot or even in an area with only dappled light, I am struggling. Without a minimum of six to eight hours of direct, unfiltered sunlight daily, I simply cannot manufacture enough food. I will become leggy as I stretch pathetically towards any available light source, my stems will weaken, and my leaf production will be sparse. My growth will be slow and etiolated because, from my point of view, I am living in a perpetual state of twilight, which is deeply unnatural for me.
You may think you are being kind by planting me in rich, fertile, black soil, but you are actually causing me great distress. In my native habitat, I thrive in gritty, lean, and often poor soils. Heavy, nutrient-dense potting mixes or garden loam retain far too much moisture around my roots. Furthermore, an overabundance of nitrogen, often from fertilizers, will force me to produce soft, weak, and flavorless growth at the expense of the essential oils that give me my wonderful aroma. I may even become more susceptible to disease. I yearn for a gritty, sandy, sharply draining mix that mimics the rocky hillsides I call home.
Perhaps you started me from a small pot and never upgraded my home. My root system, though not excessively deep, needs room to expand to support the foliage above. If I am badly root-bound, my roots have filled the entire container, circling themselves and becoming tangled. This strangles my own ability to function properly, severely stunting my growth. Alternatively, if I am planted outdoors near other aggressive plants, they may be out-competing me for water and nutrients in the soil. I need my own space to flourish without having to fight my neighbors for basic resources.
As a perennial herb, I prefer warm conditions. If the weather is persistently cool or cold, especially if I am outdoors, my metabolic processes will slow down dramatically. This is not necessarily a sign of distress but a natural response. My growth will appear to have stopped because, from a biological standpoint, it largely has until warmer temperatures return. A sudden frost can also shock my system, damaging tender new growth and causing me to focus energy on recovery rather than expansion.
