Microclimates and Ecoregions

Or Right Plant, Right Place

Choosing a plant that will grow in your garden, whether native or not, is a matter of matching up what you’ve got with what the plant needs. Check the mature size, preferred growing conditions, and other characteristics. Do they match your soil, moisture regime, amount of sun or shade and the space you have, and does it grow in your temperature zone? We have all engaged in zone-denial: that wishful thinking that you can grow something not suited to your conditions, because gosh, you love that plant! You think you will water more, or it can take more shade, or it won’t get that cold etc, etc … Feel free to continue to do that on occasion. Sometimes things work out and plants take to a spot where you did not expect them to adapt. But here’s the official line.

In this video where I go into detail about this topic, I discuss the Willamette Valley as a place defined by geology and climate. The Willamette Valley Ecoregion contains more than one type of plant community, because of differences in soils, moisture, elevation, and so forth. The nooks and crannies of the valley, and of your garden, present different microclimates for growing. Did you ever notice that a plant that was under your eaves, or next to a large shrub survived a frost better than one out in the open? That is due to the relative warmth and protection of the microclimate created by a structure or other plants.

If you want to have thriving plants, try to match the conditions they prefer. It will save you time, energy, and water. How do you do that? Here’s a primer, (and if you want the TL:DR, try this link).

Try it yourself:

  1. Look at your yard and picking out an area to work with that has one type of soil and light conditions
  2. Make a list or a chart of how it looks in different seasons – maybe there are deciduous trees that shade it in the summer, but it is more exposed in the winter. Does it have standing water? You can work with that!
  3. Find the part of the ecoregion that most resembles your conditions. This is not always easy to find, but you can start here and here
  4. Check the microclimate: is it in a low spot that gets cold, is it exposed to dry and hot conditions in the summer? This might change what you can grow. It might be more successful to pick a plant that is more adapted to the most extreme condition (heat or drought) but can also tolerate other conditions (winter wet). A bulb such as camas, for example, likes wet meadows. But after blooming in April or May, it will go to seed and be completely dormant for the summer, and it prefers to be dry so the bulb can cure. You will have an empty spot for the summer and fall there, so you can plant another shrub or perennial to grow around the bare spot later. Aster maybe, because they bloom in the fall, or a grass like tufted hair grass that likes wet soil, or roemer’s fescue if it gets very dry.

Feeling overwhelmed? Use the contact form to schedule a garden consult! I can get you started and give you a garden plan that fits your site.