It always seems odd to be talking about drought tolerance when we get literally feet of rain every year and we generally have an adequate supply of water for the summer months, but as we all know, our rainfall isn’t distributed evenly throughout the season and consequently our summers can be quite dry. Gardeners have options when it comes to selecting plants that are low water users and once established, many of these shrubs, trees, and perennials can manage quite well with occasional deep watering. Just remember, it can take 3 or more years for a plant to truly establish itself and during that time it will need close attention if we want it to survive. Here are a few of my picks for drought tolerant plants that also have some great visual interest.
Acer griseum or Paperbark Maple - If you are looking for a smallish growing tree that reaches 18 to 20 feet tall and wide, then look no more. In the spring it sports soft green three-lobed leaves that turn a dark green on top and silvery underneath in the summer. In late fall the leaves change to yellow, orange, vibrant red, and even scarlet, crimson, or pink. These leaves hang on the tree well into winter. Once they have fallen, we are left with a fantastic winter show of exfoliating bark in tones of copper, orange, cinnamon, and reddish-brown. The bark peels in curly, translucent, papery strips that remain attached to the trunk and branches until naturally worn away. It is a real eye catcher and if you want to see two nice specimens, drive down State Avenue & 10th street in Marysville to the Union Bank on the east side of the road.
Trachycarpus fortunei or Windmill Palm - Okay, I know, palm trees seem sort of out of place in the Evergreen State, but this variety will actually grow for us and oh my gosh, it is the personification of drought tolerance. Once established you can throw your garden hose away on this guy. Its single hairy trunk, that is less than a foot in diameter, can eventually (they are slow growing so have patience) reach 15 to 20 feet tall with a head of fan shaped fronds reaching 10 to 12 feet across. I prefer to see them planted in clusters of 3, but a single specimen can also be effective. The male puts out a yellow flower in spring, which is mostly a curiosity. There is a lot of seedling variation with the frond tip being either thin and drooping or short and stiff. You can decide which you prefer.
Ceanothus or California lilac - This broadleaf evergreen is not a lilac, so don’t get confused. A native to the California foothills, it has bright indigo blue flowers that will knock your socks off and thrill the honeybees. The flowers are a stunning contrast to the glossy dark green foliage that looks fabulous 12 months out of the year. The variety ‘Victoria’ grows 8 to 10 feet tall and blooms late May, while ‘Dark Star’ blooms a month sooner and only reaches 4 to 5 feet tall. ‘El Dorado’ sports attractive green leaves with a yellow margin. Plant Ceanothus in the hottest and driest spot in your garden, then sit back and enjoy.
Miscanthus or Morning Light - This is one of my favorite varieties of maiden grasses on the market. It has a narrow blade of only one quarter inch wide with a silver band running length wise and grows in a very stiff and upright clump that does not spread (none of the maiden grasses are runners). Best of all, it doesn’t flop over if we get a rain storm in late August, like we often do. It is a tidy grower topping out at only 4 to 5 feet tall and only needs to be cut to the ground once a year in February to keep it looking good.
Epimedium or Bishop’s hat - This is the consummate ground cover for a dry and partially shaded bed. The evergreen foliage looks good all winter long, but it is best to shear it back in February before the sulfur colored flowers emerge with their clusters of dainty little bishop hats. The new foliage is often mottled with a tinge of red that matures to a pleasant medium green. There are actually several varieties on the market with different leaf and flower coloration. This plant spreads slowly so it won’t take over your garden.
For more plants suitable for our dry summers I would suggest you consult The Plant List, a publication developed by the City of Seattle Public Utilities and reproduced with permission by Snohomish County. This brochure is an excellent reference for all types of plants that will thrive in our gardens whether they are wet or dry.