Climate - Micro & Macro

There are two aspects to consider for climate – what is the general climate of your area, and what are the specific characteristics of your piece of property.  Climate zones describe the macroclimate or general characteristics of your area.  By learning your climate zone you can gain a lot of useful information such as average minimum temperature, weather patterns and number of growing days.  The specific characteristics of your property are your microclimates and these you learn by observing. Microclimates are determined by soil, slope, aspect, wind and water.  If you have a small backyard plot you may not have many microclimates, but if you have a parcel with some slope and differing vegetation you’re likely to have several.  Once you identify your microclimates you can use them to your advantage when planting fruit trees.  

Climate Zones

The Northcoast and Mid Klamath region encompasses a wide array of elevations, soils and topography that have given rise to one of the most diverse flora and fauna of any temperate zone on earth.  This same complexity yields a range of opportunities and challenges for farming and gardening.  It is possible to grow fresh produce year round on low elevation valley floors and river bars, while higher elevations and north facing drainages are some of the coldest climate zones in the West.  Banana belts offer microclimates that escape frosts, extending the growing season by many weeks on some sites. 

Identifying your climate zone and microclimates will help clarify the challenges and opportunities of gardening in your area and provide a way to adapt information to your specific site.  Most gardeners are familiar with the USDA climate zones that reference a plants hardiness (or tolerance to cold).  The climate zones developed by Sunset Gardening are much more detailed and are a better resource for our area.  However, since most plant tags reference the USDA zones, we have included it as an additional reference.  Many of the charts and calendars listed on this website are based on Sunset climate zone 14, which includes the lower elevations of Orleans, Hoopa Valley and Willow Creek. 

You can learn more about your climate zone in the Sunset Gardening Book for your region or by visiting the Sunset website. You can find out your annual minimum average temperature by consulting a knowledgeable neighbor, your county agricultural extension, or the USDA climate zone map.

Don’t be afraid to experiment – Keep in mind that a climate zone is the map, and your site the actual territory. Most written advice (this catalogue included) will be conservative by necessity. Climate zones do not account for your slope, aspect and local weather, warm spots and frost pockets. These all add up to your local microclimate, which may vary from what a climate zone tells you. Use the climate zone as a guideline, not an absolute. Use the information in this catalogue to make educated choices and avoid varieties that are obviously not suited to your climate. Don’t be afraid to experiment and try something new. Ultimately the only way to know how a fruit will produce on a specific site is to plant it there.

Microclimates - Make the Most of your Location

Microclimates are small pockets of climate variations that differ from the surrounding climate. By identifying and using microclimates you can grow fruit not normally recommended for your climate zone. Pay attention to the way the sun travels across your property throughout the season. Look for cold spots and hot spots. A maximum-minimum thermometer placed at different locations will tell you a lot about your microclimates. Here are a few other things to look for.

Slope – Bear in mind that cold air moves like water, so in spring and fall a valley floor will usually be significantly colder than a slope. In fact, some slopes are called banana belts, because they remain frost-free much longer than valley floors, which may be subjected to hard frosts. If you are in a warm climate and are concerned about not having enough chill, plant in low spots when possible. If you are in a cold climate and are concerned about frost damage, make the best use of slopes when available.

Aspect - A south-facing slope is, of course, much warmer than a north-facing slope. Western slopes receive the hotter, more intense afternoon sunshine, while eastern slopes receive the less intense morning sun. A south facing wall is a good place to plant a tree that needs extra heat in order to ripen. If the wall has an overhang, it will also provide some frost protection.

Thermal mass – Water and stone will absorb heat during the day and re-radiate it at night. A stone or brick wall can be an ideal place for ripening a late fruit crop. Translucent jugs of water placed in a greenhouse or around fruit trees will re-radiate heat at night. A small pond will serve as a heat sink in the summer and fall, and a cold sink in spring and winter. Watering before an anticipated frost will increase re-radiated heat – the wet soil will absorb more heat than dry soil during the day, and release more at night.

Wind – Strong wind can desiccate plants, damage fruit and decrease air temperatures. Wind protection can be especially important in coastal or desert regions. The best windbreak is one that slows wind down rather than stopping it. Hedges, vines, lattice fences and screens allow some wind to pass through without creating turbulence.