I utilize them in containers and client landscape designs as evergreen punctuation marks and tropical contrast against neighboring trees and deciduous shrubs. After our recent “arctic blast” in both December and January, large and small specimens
around town are looking rather spent. Record shattering cold temperatures in Oregon coupled with up to 14” of snow and ice smashed even the largest blades of Phormium tenax ‘Atropurpueum’ just from the weight.
Winter Protection Options
To provide a blanket of warmth when predicted temperatures dip into the twenties, place evergreen branches through the crown. Another way to protect phormiums is to use Reemay Lawn and Garden Blanket. Reemay is packaged under the name Typar® Landscape Products. Reemay is a lightweight landscape fabric that holds frost off, retains heat and doesn’t crush foliage. Wrap the fabric around the plant like a cage. Place netted Christmas lights over the top to melt the snow. This approach will keep the plant warmer, protect blades against winter winds and will not weigh it down.
Will It Survive?
If the Phormium is a decent size that happened to put on substantial growth during the prior season, it has a pretty good chance of rebounding. However, if the specimen is small or did not push out new blades in the summer it might not fare as well. When temperatures dip into the teens, what often makes a difference for plant survival is how well established the root system was before the winter chill arrived. Drought-stressed plants are also less hardy to freezing temperatures. Even though fall is one of the best times to plant in the Willamette Valley, Phormiums may increasingly be a better bet if planted out in the landscape or containers in springtime.
|Habit & Cultural Details
||Cold Hardy Phormiums for Western Oregon
Family: Phormiaceae (Phormiums)
Zone: 8a (10º to 15ºF)
Origin: New Zealand (Australasia)
Bloom Time: Infrequent
Width/Height: Depends on variety
Exposure: Sun or Shade
Irrigation Required: Medium Water Needs
Phormium tenax (Green)
New Zealand Flax. Handsome green leaves up to 3" wide and 5' tall. Forms an impressive clump in short period of time in compost-rich soil with regular water in summer. Full sun to light shade. Phormiums that are well watered during summer will be much better adapted to deal with winter cold. Regular water in containers.
Phormium tenax ‘Atropurpureum’
The most commonly seen form of New Zealand Flax. Grows to 5' tall and 3' wide after several years with deep bronze/maroon leaves. Leaves become wider as the plant matures. Rich soil with regular irrigation in summer and fertilizer in full sun. Great large container plant. Regrows after big freezes.
Phormium tenax 'Rubrum'
Upright strap-like foliage forming a vase shaped clump. Many forms of varying leaf color and variegation. Site in a protected area with well-drained soils for best results. Reddish-purple foliage provides a unique garden accent.
My initial inclination was to get outside and begin clean-up duties immediately. Old man winter has continually forced my Felco’s to take a concerted wait and see approach. I will be cutting away any damaged foliage while avoiding the smaller blades in the middle giving them time to recover. It is always a good idea to keep the area under all your plants clear to reduce pests and diseases harboring over under a winter blanket of leaves and debris. An alternative approach is to prune back Phormiums down to the ground and mulch heavily with compost.
What to Look for This Spring
Phormiums will wait to put on new growth from their base until the weather starts to warm up. They are heavy feeders and appreciate an all purpose organic fertilizer application on a regular schedule. Keep them well watered in the summer to avoid leaf scald. Easy care and versatile, this evergreen perennial can provide years of enjoyment if they are treated well throughout the gardening season.
BeeDazzled Gardens & Designs Specializes in creating fragrant, organic, low maintenance garden vignettes that add value and pleasure to a home or business exterior and landscape. Our specialty is staged, perennial bed planting designs, seasonal potted containers and garden renovations. Learn more about Dawn at her profile on the Mulch.
Photo credit on all photos: Dawn Hummel