When I first moved to the maritime Northwest, I found the cool, grey summers a little depressing. As I discovered how well gardens responded to the understated weather, I quickly became a convert. Not only did garden plants thrive, but every color combination I assembled was enhanced by the subtle, silvery skies. OK, the tomatoes didn’t always do so well, but greens grew just fine, and I could get anything else at the farmer’s market.
After the weather we’ve had over the past decade (or more), those silvery summers seem like a long-ago dream of a greener, moister time.
Garden plants weren’t the only ones that loved our once-gentle climate, where rain was plentiful even if warmth wasn’t. Native plants, from cedars and firs to sword ferns and salal, also throve, supporting and nurturing an enormous circle of living critters. Since many native plants had developed a tolerance for dry if cool summers, I never thought I’d suggest that native plants could use supplemental water as I’ve done in recent summers. However, long periods of unaccustomed heat and drought left native plants more susceptible to diseases, from powdery mildew on bigleaf maples to die off of young red cedars, whose shallow root systems make them especially vulnerable. Unimaginable as it once seemed, summer watering may indeed help save our iconic evergreen trees.
The maritime Northwest is hardly the only area to see such changes. In 2000, NOAA founded a US National Drought Monitor to track drought conditions state by state, county by county, and even by ZIP code. (If you want to take a peek, it’s at https://www.drought.gov/states/washington/county/kitsap) When you study weather maps from around the country and the world, it’s clear that this is still one of the most favorable climates anywhere these days. That said, many of our gardens are hurting and would benefit from some TLC.
Back in the day, the arrival of October rains signaled gardeners to start planting perennials, reorganizing beds and borders, and moving woody plants freely. These days, there’s no telling when the rains will arrive or how long they’ll keep coming. That’s fine for bulbs, which can go in the ground anytime from now until mid-December, but makes it trickier to transplant anything well-established. If you’re planting or moving woody plants, make sure the planting hole is well saturated, including a wide swath around it. Otherwise, the dry surrounding soil will suck that moisture away, stressing plants that are desperately trying to grow new root systems.
To refresh lawns, rake in an inch or so of compost to prevent thatch build-up and red thread. Next, spread corn gluten at the rate of 2 pounds per 100 square feet of lawn; this adds slow-release nitrogen and suppresses weed germination at the same time. To make beds and borders more resilient and reduce the need for supplemental water in summer, increase the humus content. Before you begin soil therapy, water each bed to a depth of at least 2 inches. If the water sheets off the dry soil, wet the soil down lightly, wait 15-20 minutes, then water again more deeply as the soil regains absorbency. Instead of tilling, simply layer on granulated humic acid at the suggested rate (usually about half a pound per 100 square feet). Next, layer on 2 or 3 inches of compost, then water again, using the same light start and deeper follow-up. Layer on any fallen leaves you can gather and hope for a wet winter. Onward, right?
Contact Ann Lovejoy at 413 Madrona Way NE, Bainbridge Island, WA 98110 or visit Ann’s blog at http://www.loghouseplants.com/blogs/greengardening/ and leave a question/comment.