For those just getting into gardening during the pandemic, there is so much to tell you, so much to convey about how to garden in our corner of the Pacific Northwest. We are fortunate in having a mild climate for all sorts of growing, but also face some challenges.
But first to our climate.
In North America, we use U.S. Department of Agriculture hardiness zones to determine what sorts of plants will thrive. This is a numeric system, which quantifies how cold it gets in an average winter, ranging from a low of 1a (-60 F, as in northern Alaska) to a high of 13b (65 F, as in Puerto Rico). We are a comfortable 8a (10 F) – the same as most of Britain, with its world-class gardens.
Hardiness zone determines which plants will survive the winter, so we are fortunate in being able to winter over all sorts of popular ornamental and food plants. How great is that?
Summers are generally mild, sunny and dry – much like our unusually balmy April this year. This makes working outside pleasant, but the aridity challenges gardeners. Unlike the distributed rainfall that British and East Coast plants receive, ours receive virtually no rainfall in summer.
Native plants thrive in these conditions, and gardening with them is highly recommended. Xeriscaping, or dry gardening, is not: those plants will rot in our cold winter rains.
Many desirable non-native ornamentals and edibles grow vigorously in our summer sun and long days, but get thirsty. Unless you want to spend summers dragging around a hose or watering can, you must invest in an irrigation system – a drip system if your plants are permanently sited or an in-ground spray system for broader or more flexible coverage.
Another climate characteristic is that our growing season is approximately eight months, between the last frost at the end of March and the first frost at the beginning of November.
This limits the cultivation of edibles developed in climes with a longer and hotter season, especially those that will not tolerate our usual April temperatures or our October cold rain.
Basil, eggplant, okra and tomatoes will not even make it into October. Tomatoes rarely receive enough prolonged heat to yield huge luscious beefsteak tomatoes – unless you have a greenhouse or an especially warm sunny garden.
So if you are committed to growing a particular vegetable or fruit, check out its ‘days to harvest’ before buying it. The smaller the number, the more likely you are to eat well.
We can extend our season a little by using shoulder-month protection like floating row covers in vegetable gardens, but you might be happier simply growing some cooler season crops, like chard, kale and garlic.
Popular ornamentals have a better time of it, so feel free to invest in your favorite annuals and frost-hardy perennials.
If you like early spring color, invest in spring bulbs like daffodils, Muscari, and bluebells (squirrels, voles and deer eat tulips) and spring-blooming hardy perennials, like pasque flower and wallflowers. On the other end of the calendar, Echinaceas and Rudbeckias will supply early autumn garden color. In between, grow almost whatever you want.