Northwest offers opportunities for a long growing season

Jeanne Crisp and Julie Kelly

We don't want to throw cold water on anyone's garden dreams, but some restraint may serve you well. When you see blooming plants for sale or seed packets glowing with tasty-looking vegetables, it's tempting to dive right in. But if you plant some crops too early, and your plants die or your seeds never germinate, you may reinforce your belief that you "can't garden."

The Northwest offers ample rainfall, good soil, and moderate temperatures for a long growing season. As you plan your gardening year, think in terms of three waves of plants: cool weather crops (lettuce, carrots, cabbage), warm weather crops (tomatoes, cucumbers, peppers), and fall/winter crops (cool season crops that can tolerate a light frost). Look up "Tilth Alliance planting calendar" online (https://bit.ly/3wbRDpf) to find a 1-page chart that summarizes planting and harvesting dates for three dozen popular vegetables.

For example, you'll see you can plant lettuce in March to harvest in mid-May through August. Then you can plant a second crop of lettuce in July or August to harvest into the fall and winter. However, tomatoes or peppers are warm weather crops that are planted in May or June for harvest in August, September, or October.

Get the most out of your garden by planting a sequence of cool, then warm, then back to cool season crops. For example, in the spring plant radishes, peas, lettuce and spinach where you plan to plant your tomatoes and summer squash in late May and June. Then in September you can plant beets and kale for harvesting in spring.

In deciding what to plant when, science is your friend. One inexpensive purchase, a soil thermometer, will help you make good decisions. When you look at a planting calendar, you'll understand why spinach can be planted in early spring, while tomatoes need to wait until May or early June. Spinach can germinate when the soil temperature – not the ambient temperature – is a minimum of 50 degrees. Warm weather crops – seeds or seedlings - won't be happy until the soil is at least 60 degrees.

You can hasten the heat if you opt for covered gardens, or dark row covers, or other such enhancements. But if you want to start with a simple approach while you experiment and gain confidence, buy a soil thermometer, monitor temperatures, read the seed packages or growing charts, and plant accordingly. And be aware that the location of your garden can impact soil temperatures. A bed along a south-facing wall will warm up faster than a plot dug

into partially shady ground. A container on a sheltered deck will probably warm up faster than a raised bed in the middle of the yard.

Soil temperature is important for seeds to germinate. For warm weather crops to ripen, air temperature is also important. (Ever grown a beautiful tomato plant with lots of "green" tomatoes?) For success, choose short season varieties that are bred to produce under cool conditions and in a shorter period of time.

So, as you plan your campaign, think about the waves we mentioned earlier. You may have a few spots that are ready now for lettuce or spinach. In another month or two, more areas will become suitable for those warm weather crops. Space out your efforts, respect Mother Nature and all the research that's been done to inform our decisions, and have fun anticipating your results!

Visit the Mukilteo Community Garden website, mukilteogarden.org, for more information on growing vegetables in our fair city.