Beaumont-Wilshire: The Real Dirt
Take a walk in Beaumont-Wilshire and you will see some amazing rock gardens. These gardens are one reason I wanted to move here in 1976. The old gardens I fell in love with are going strong and some of us have built additional ones.
In winter many of our perennials die back to rest. This happens in rock gardens also, but many plants we put there have valuable winter interest. The rocks don’t rest; they carry on with a sculptural quality enjoyable any time of the year.
Rock gardens can provide microclimates for many kinds of plants. If you place the rocks carefully, you can create small areas of shade, or blazing hot spots. Many rock garden plants need sharp drainage, so add sand and ¼ 10 sharp gravel to your soil as you are building. Plants near rocks can run their roots underneath where they stay protected and find moisture during our dry summers.
Conifers are great for year-round interest. Some cultivars have been developed to stay small. Take a trip to Garden Fever and Portland Nursery to see a huge variety of small conifers: pines, cypress, hemlocks, and more. Read the fine print! Make sure the tree will stay small and not overwhelm your rock garden.
Look into our native “shrubby” penstemons: P. cardwellii, P. davidsonii. These guys grow on rock faces in the Cascades, (go to Johnston Ridge, north of Mt St Helens in early June). My penstemon plants have been happy since the early 1990s. The perennial leaves are great in the winter, and the flowers in spring can’t be beat.
Hardy succulents soldier through the winter. A wide variety of foliage shapes and colors are available. Some change color in the winter.
Plant crocuses. The little snow crocus can bloom in January in one of the sunny, sheltered places you create in your rock garden. Some of the small species tulips also bloom early. Another bulb to consider is Cyclamen hederifolium. The pink and white flowers show in early autumn, and the beautiful leaves cover the soil all winter long before dying back in the spring. Ants love the Cyclamen fruit and spread the seed, which grows in well-drained soil.
I used lava rock to build my garden. It has small holes on the surface that anchor wonderful mini-gardens of lichens and moss that also stay green during the winter. I have even had small ferns anchor themselves on this rock.
Take a walk in our neighborhood. There is a lot to see in gardens in the winter and lots of examples to inspire us.
Resources: Columbia-Willamette Chapter of the North American Rock Garden Society meetings, website: http://www.cwnargs.org/
Christopher Grey-Wilson, The Rock Garden Plant Primer, Timber Press.