Within every planting zone, your own growing environment has its own microclimate. It is important to get to know your own microclimate before or as you grow.
A microclimate is the distinct climate of a small area. A microclimate can differ from the climate of the surrounding area based on topography, man-made structures, bodies of water, infrastructure, and the terrain. Each of these aspects can shift the growing environment in subtle ways that can impact temperature, wind conditions, humidity, water run off, and access to the sun.
The easiest way to explain microclimate is to give a few examples.
1) My farm is located in a valley (topography) with pasture directly surrounding the main flower beds. The wind is funneled down the valley and can cause the temperature to drop as cold air slides down the valley. Pasture surrounding the farm means that there is no wind break. On my farm, due to this unique microclimate, I need to be careful to stake plants and be prepared for slightly colder temperatures. Creating a natural wind break through native perennial shrubs and bushes is on my list of future projects.
2) Part of the farm is built into the side of a berm (topography). Within the farm there is an even smaller microclimate next to this berm that benefits from wind protection. This area is able to protect more fragile crops.
3) Another section of the farm is built along a fence line surrounding a house (man-made structure). The house provides protection from wind in the winter and early morning shade in the summer.
4) I harvest from the forest surrounding the farm (terrain). This is its own microclimate with differing temperatures, wind speed, and solar radiation.
5) I have a drainage spout (man-made/infrastructure) that empties into the side of a flower bed on the farm. The bed is not affected by the drainage, but the path next to the bed slowly gets eroded over the course of the growing season. This area is where I have the most issues with weeds because of the eroded bed and the rich soil that collects in this spot. While this doesn't have an effect on the climate (temperature/wind/humidity/solar), it is an observation of how the surrounding environment affects my farm.
By growing plants by a lake, in the city, on a mountain, in a valley, on a balcony, by a river, on a lot between high rises, your microclimate can differ from someone growing flowers down the street. In fact, you may find that different beds in your yard, garden, or farm freeze before other beds, get more water, or are protected from wind more than other beds. It is all about observing how your patch of land is affected by the climate around it and taking notes.
I also want to mention that I take into consideration our "typical" local weather patterns. My region can get a lot of rainfall during the summer. We get 54" of annual rainfall. Powdery mildew becomes a problem every summer because of all the rain. I am in zone 7a. Other regions of the US in zone 7a, such as central Washington state, get 7-9" annually. I take into account my regional climate even as I think about my growing zone and microclimate. All of this, together, helps me figure out what to plant, how to plant, and how to grow flowers on my unique farm. Every farm is different. The key is to figure out what works for you and your unique environment.
Thinking about microclimate is an exercise in observation. Observe your patch of land and take notes on how different crops grow, weather patterns, and the effects of temperature, humidity, wind speed, and sunshine. There's always more to learn.
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