From our perspective, light is not a luxury; it is our food. The process of photosynthesis, which converts light energy, water, and carbon dioxide into the sugars we need to grow, is our sole reason for reaching towards the sun. For Greek oregano (Origanum vulgare subsp. hirtum), a Mediterranean native, we are genetically programmed to crave intense, direct sunlight. To truly thrive indoors and produce the potent, flavorful oils we are known for, we require a minimum of 6 to 8 hours of direct, bright light daily. A south-facing window is our ideal spot in a US home. Without this, our growth becomes weak and "leggy" as we stretch desperately for any light source, and our essential oil production—and thus our flavor—diminishes significantly.
Our roots have a critical need: they must breathe. In our native, rocky hillsides, water drains away quickly, preventing rot and fungal diseases. The single greatest threat to our survival indoors is being planted in heavy, moisture-retentive soil. We demand a well-draining potting mix. A blend formulated for cacti and succulents is excellent, or you can create a mix using regular potting soil amended heavily with perlite, coarse sand, or pumice. Equally important is the container itself; it must have ample drainage holes. Sitting in waterlogged soil is a death sentence for us, as it suffocates our roots and leads to a rapid demise.
Our watering needs follow a distinct cycle reflective of our homeland. We prefer a cycle of thorough watering followed by a period of drought. The best method is to check the soil about one inch below the surface. When that top inch feels completely dry to the touch, it is time to water us deeply until water flows freely from the drainage holes. Then, allow the pot to drain completely and do not water again until the soil has dried out once more. We are far more tolerant of underwatering than overwatering. Soggy conditions will cause our roots to rot and our leaves to yellow and drop.
We are comfortable in the same temperatures that you are. Average US household temperatures, ranging from 65°F to 75°F (18°C to 24°C), are perfectly suitable for our growth. We appreciate good air circulation but despise being placed directly in the path of hot, dry air from heating vents or cold drafts from air conditioners and leaky windows. While we are adapted to low humidity, the extremely dry air common in heated homes during winter can sometimes stress us. A occasional light misting or placing our pot on a pebble tray with water can provide a slight humidity boost, but it is not usually a critical requirement.
We are not heavy feeders. In fact, too much fertilizer can lead to excessive, soft leafy growth at the expense of the potent flavor you desire. A light feeding once per month during our active growing season (spring and summer) with a balanced, diluted liquid fertilizer is more than sufficient. Do not feed us during the fall and winter when our growth naturally slows. Most importantly, you must prune us. Regularly pinching off the tips of our stems encourages us to become bushy and full instead of tall and sparse. It also prevents us from flowering, which directs all our energy into producing the flavorful leaves you want to harvest.
