In this video we tour our foodscape and talk about how understanding microclimates in your region and around your house can help you grow more food.
Elevation and cold air drainage
The video features an almond tree in full bloom and starts by discussing how almonds aren’t typically grown in Northern Utah but can be successful in particular microclimates.
In Northern Utah, fruit and nut growers need to consider the possibility of late spring frost that can damage developing flowers and fruit. The safest way to increase likelihood of success would be to choose late blooming trees apples, for example, bloom much later than apricots and almonds. It may also be wise to seek particular varieties that bloom later; many Utah peach growers select late blooming varieties that have longer ‘chilling requirements’. Read more about ‘chill hours’ here. However, even along the Wasatch Front in Utah elevation can have a major impact on microclimate. Cold air tends to drain down slopes and often settles in low areas. Due to cold air drainage, locations with slightly higher elevations in bench and foothill areas of Utah (and other mountainous regions) often escape the coldest temperatures during spring frost episodes. Here is a useful diagram from USU Extension:
I think one reason we have been able to successfully grow almonds in Utah is that we live on the Ogden bench, whereas lower areas nearer to the Great Salk Lake would be much more prone to spring frost. Another reason is that we are making the best use of the microclimates around our foodscape. Cold air moves downhill not only regionally but also around our properties. Our almond trees are carefully placed at the top of a slope, near our house where cold air can naturally flow away.
Passive solar heat retention
By placing the almonds near our house, we can also take advantage of the microclimate created by our west-facing brick wall. The video also shows a fig tree up against a south facing brick wall. These walls absorb heat during the day and then radiate that heat overnight, which can add a few crucial degrees.
When planning placement of your fruit and nut trees definitely consider slope and sun exposure. It is also a good idea to consider sun, shade and wind exposure all around your foodscape when planning all your fruits and vegetables. Some vegetables, including leafy greens like spinach and lettuce, do well with some afternoon shade. In the video we show our favorite area to grow lettuce where afternoon shade delays bolting (flowering and becoming bitter) in the summer. On the other hand, vegetables that actually create a fruit such as tomatoes, peppers, cucumbers, squash, etc really produce best when there is no shade at all. Our video tours an area in front of our house where there is nonstop full sun sunrise to sunset.
A major focus of the video is how it can be tremendously beneficial to think about not only your winter hardiness zone but also how weather and microclimates change throughout the season. For example, the north side of our house is the coldest microclimate in the winter because of the shade of the house, but the hottest in the summer when the house casts a very small shadow and the area receives sun all day.
More resources on microclimates:
Climate and Microclimates (Taun Beddes, USU Extension)
Mountain Microclimates (Susan Fernalld, Colorado Master Gardener)
How to determine your microclimate (WSU Extension)
Learn more about Critical Temperature for Frost Damage on Fruit Trees (USU Extension).