Seattle and the greater Pacific Northwest can be a tricky place to predict weather patterns. The area is full of potential for amateur gardeners, but finding the perfect time to plant the perfect flower can sometimes be difficult, and requires a bit of research before you set out to design your garden.
Pictured above, clockwise from top left:
1. English Roses are a great way to get started on a summer garden. The British Isles have a climate that closely resembles that of the Pacific Northwest (although they do get more rain during the summer months). The heaviest blooms arrive in the early summer, and repeat towards the end of summer or beginning of fall, depending on climate and specific rose type. English Roses like at least six hours of sunlight and regular watering and fertilizing. Photo from David Austin English Roses.
2. Dahlias are a favorite of mine! Sweet, annual explosions of color, these perform the best when planted in full sun light with regular water. Soil-level watering to avoid powdery mildew, as well as stake-support and disbudding help these blooms thrive. Plant the bulbs just after the first frost, which is usually around the beginning of October, for spring blooms. Photo from Swanson's Nursery.
3. A lovely sign of spring in Seattle: the Sweet Pea! Growing Sweet Peas in the PNW climate is quite easy. Mild winters are the kindest to these buds. Sow the sweet peas in the fall for a spring bloom, or in the late spring if there has been a colder winter. We know the name is tempting but don't eat Sweet Peas — they're poisonous!
4. Last but assuredly not least, the beautiful and resilient Goldflame Honeysuckle. This vine grows upwards to 10-15 feet with a sturdy support. Give it a wide radius from other plants (between 3-4 feet). Honeysuckle needs good air circulation around it to avoid attacks by powdery mildew and fungal disease. Goldflame Honeysuckle blooms the best in early June, and continues to bloom well into the winter. Most varieties of Honeysuckle thrive in the Pacific Northwest, so choose your favorite (with a bit of research). Photo via Monrovia Nursery.
(Images: as credited above)
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I love hydrangeas, and they grow like gangbusters here. I recently got a really pretty one at Molbak's. The colors look like they were done in watercolor, they are so beautiful.
I also picked up an abutilon red tiger at the garden show. It isn't good for garden planting here, but does really well in a container brought in in the winter, which is great because I am a balcony container-gardener. It grows up to 5 feet tall, though, so you have to have room for a pretty leggy houseplant.
Presumably everyone in the state already knows all about rhododendrons, but there are some really amazing varieties out there that you can see at the Rhododendron Botanical Garden in Federal Way.
Black Spot and Powdery Mildew are 2 problems found with roses in the PNW. Even David Austin Roses are susceptible. Rugosa Roses and PNW Native shrub roses are great for disease resistance flowers, screening, lovely fragrance and colorful hips.
http://county.wsu.edu/king/gardening/mg/factsheets/Fact%20Sheets/Disease%20Resistant%20Roses%20for%20the%20Puget%20Sound%20Area.pdf
A traditional time to plant sweet peas here is Valentines Day.
Dahlias are awesome, but do rot in poor draining soil and some people dig up their bulbs for the winter. I also love how profuse they are...my kids used to pick off the heads and use the petals like confetti, and there were so many flowers I did not care. They are also great because you can plant them right now when you are kicking yourself for having forgotten to plant tulip bulbs in the fall :).
Speaking of tulips, "Princess Irene" blossoms looks like flames and are fragrant to boot.
http://www.tulips.com/products_view.cfm?PID=167
There are even native honeysuckles that the hummingbirds love.
Some varieties of hummingbird mint (agastache) will overwinter, some are hit or miss... One that flowers for 6-8 weeks in my garden is Agastache "Firebird." Goregeous shades of reddy-pinky oranges, with leaves that smell fantastic. Way easier than maintaining a hummingbird feeder and prettier too.
http://www.lazyssfarm.com/Plants/Perennials/A_files/Ac-Ag%20Images/agastache_coccinea_rupestris_firebird.htm
Another perennial that blooms forever and looks amazing with a variety of different colors is
Penstemon "Electric Blue." Especially glowy in the early evening light.
http://somersetflorist.net/images/Penstemon_Electric_Blue_Beardtongue_.jpg
What is it with people who think that the whole Pacific Northwest is like Seattle? This area has at least two very different climates: the part to the west of the mountains (where Portland and Seattle are) are mild, cloudy, and rainy, while the part to the east is dry (including some DESERT areas) with hot summers and cold winters. The PNW does not have a similar climate to the UK; Seattle does!
STH: That is why the title of the post is the best flowers to grow in Seattle.