The last week of May is a great time to plan for a summer garden project, adding a shade garden, planning for more summer color or just indulging your wish to collect beautiful, blooming plants.
This week you can fulfill all three wishes by planning to plant more hydrangeas into your landscape. Last year I started a hydrangea garden room – an open area among the trees surrounded by a circle of hydrangeas. The idea is to walk into the opening and be surrounded by walls of blooming hydrangeas. I’ll keep you posted on how it comes out.
Hydrangeas are tough wind-, cold- and salt-spray-resistant shrubs that love to grow in our cool summer climate. They bloom in sun or partial shade and are super easy to start from cuttings made in early summer. So what’s the No. 1 question asked about growing hydrangeas?
How and when do I prune my hydrangea?
The answer is: It all depends.
First, figure out what type of hydrangea you have or what type you need.
This is the big shrub with the huge spheres of “mop head” midsummer blooms, usually blue or purple in our naturally acidic soil. This species can handle salt along the coast but does need water or it will wilt in the summer sun. For a more refined look, grow the lace cap hydrangea, the frilly cousin to the mop head look. New dwarf hydrangea varieties such as Pink Elf, Mini Penny and Buttons and Bows make this a shrub that does great in containers, and the naturally compact size of these new dwarfs mean they rarely need pruning. A full-size but compact growing hydrangea called Nikko Blue displays the most intense color and numerous blooms on a shrub that can grow to 6 feet. The new Endless Summer hydrangea blooms on new wood, perfect for very cold or small gardens.
How to Prune: The time to prune big leaf varieties is in February, removing the previous summer’s faded blooms along with a length of stem. Endless Summer hydrangeas can be pruned anytime they need it; cutting this shrub just encourages more flowers.
FOR THE ARISTOCRAT GARDEN OR SMALL SPACE LANDSCAPE
This cream-and-peach blooming shrub is best grown as a small tree where it can flower on a 10- to 12-foot framework showcasing its rich, creamy colors that intensify as autumn arrives. More formal than the big leaf hydrangea, it has blooms that are large but pointed or cone-shaped, and the color cannot be changed by the acidity of the soil. My own Pee Gee hydrangea thrives in rather poor soil with no extra summer water, and the midsummer blooms last until November. The cream flowers turn pink, then rose, then russet as autumn arrives. The colors look spectacular when grown near a brick building.
Look for Pee Gee varieties Pinky Winky, with huge blooms, Pink Diamond, which survives colder temperatures, and the largest of the three, Angel’s Blush.
How to Prune: Best when pruned in early spring (I get snippy with mine in March), and the more branches you thin out, the larger the remaining flowers will be. Shorten the longest branches by half, as this hydrangea flowers on new wood – so be warned. If you wait and prune too late in the spring, you’ll be cutting off buds and miss a year of blooms.
FOR WOODLAND GARDENS, PINK THEME GARDENS, HEDGE PLANTINGS
A breeding breakthrough, the new Invincibelle Spirit hydrangea stays pink even in our acidic soil, and some of the profits from this cold-resistant, pink hydrangea will be donated to breast cancer research. Give this shade-lover a few years to build up strong stems, and shorten the new growth by half in early spring – or else the young stems will flop when they bloom.
How to Prune: I’m still experimenting with the best time to prune this hydrangea – but mine did well in the shade.
Marianne Binetti is the author of “Easy Answers for Great Gardens” and eight other gardening books. She has a degree in horticulture from WSU and will answer questions from her website at www.binettigarden.com.