Based on the wording of your question, I assume that you are interested in plants native to Washington and would recommend two books:

Kruckeberg, Arthur R., Gardening with Native Plants of the Pacific Northwest, University of Washington Press, Seattle, 2nd edition, 1996.
Pettinger, April, and Brenda Costano, Native Plants in the Coastal Garden - A Guide for Gardeners in the Pacific Northwest , Timber Press, Portland, OR, revised edition, 2002.

The Washington Native Plant Society is also a good resource.

If you are interested in plants that will grow well in your area, but are not necessarily native to Washington State, please check out the Miller Library's booklist about gardening in the Pacific Northwest.

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Date 2007-12-13
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Native Plants in the Coastal Garden (by A. Pettinger, 2002, p. 27), says the following about mulching Pacfic Northwest native plants:

...When an established native plant garden requires maintenance, it is usually minimal: mulching is probably the most important---and often the only---maintenance required. In any garden, mulching is arguably the most beneficial care you can give your soil and your plants. There are many advantages to using mulch. It suppresses weeds, conserves moisture by minimizing evaporation, and releases nutrients to the soil...Good mulch materials are compost, decaying leaves, well-rotted manures, sea kelp, mushroom compost, seedless hay or straw, shredded prunings, natural wood chips, grass clippings and evergreen needles and cones. Commercially available screened bark---usually referred to as bark mulch---has little to offer other than its ability to conserve water; it has no nutritional value and in fact depletes the nitrogen in the soil. When spreading mulch, don't pile it too close to stems of plants. If you are using compost as mulch, spread it about 2 to 4 inches deep. Other materials may be applied to a depth of 3 to 7 inches...

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Date 2006-03-20
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Here is what I found on the web page of the Royal Horticultural Society. The correct name is Cistus x purpureus.

The Cistus website (a British site) has a photo gallery which shows there are both spotted and unspotted varieties of this plant, and there is even one which is white with spots, despite the purpureus in the name. Here is one without spots.

Here is information about Nandina domestica 'Royal Princess.'

Here is an excerpt from San Marcos Growers site:

Nandina domestica 'Royal Princess' (Heavenly Bamboo) - This is an upright growing shrub to 6 to 8 feet tall has very lacy foliage. Pinkish white flowers bloom in clusters at the ends of branches in the late spring and summer followed by a heavy set of red berries ( notably heavier than most Nandina cultivars). The foliage turns to burgundy in spring and later a orange-red in fall. Branching stands stiffly upright unlike typical Nandina domestica and the foliage has a much finer texture. Plant in sun or shade. Tolerates fairly dry conditions but looks better when given water occasionally. It is hardy to about 10 degrees F.

Nandina is widely grown in our area, and so far has not exhibited the invasive properties it has in the Southern U.S. Several cultivars are listed on the Great Plant Picks website, which is created by local gardening experts, so I am assuming there should not be a problem with growing it here. If you are still concerned about it, the main way it becomes invasive is from the berries setting seed and spreading. You could plant native ornamentals in its place, if you wish. Here are links to information about native plant landscaping:

Washington Native Plant Society
www.plantnative.org
King County's Native Plant Guide

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Date 2007-03-28
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If you do decide to look for alternative vines to grow, scarlet runner bean is attractive to hummingbirds, as are honeysuckle (harder to grow than Campsis as it has occasional problems with aphids), and clematis, according to Naturescaping, published by the Oregon Department of Fish and Wildlife (2001).

The local website of Rainyside Gardeners has a list of nectar plants for Northwest hummingbirds. Of the plants on this list (which includes Campsis radicans, Honeysuckle(Lonicera), and Scarlet runner bean), Eccremocarpus scaber, Ipomoea, Jasminum stephanense, Mina lobata, and Tropaeolum are all vines, some of which are annual.

Washington Department of Fish and Wildlife also has a plant list for attracting hummingbirds.

King County Natural Resources has a searchable native plant guide, and here are the native plants they recommend for hummingbirds:

• Tree:
  • Madrone; madrona (Arbutus menziesii)
• Vine:
  • Orange honeysuckle (Lonicera ciliosa)
• Shrub:
  • Red-flowering currant (Ribes sanguineum)
  • Black gooseberry (Ribes lacustre)
• Groundcover:
  • Thrift; sea pink (Armeria maritima)
  • Western columbine (Aquilegia formosa)
  • Cooley's hedge nettle (Stachys cooleyae)

In my own garden, the Italian Jasmine (Jasminum humile, a shrub grown against a wall, not a vine) which is very appealing to hummingbirds, and in the fall they seem to like the Camellia sasanqua.

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Date 2008-05-21
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