16 Michigan Gardener a August 2010

Eric Hofley / Michigan Gardener This ‘Color Guard’ yucca survives each winter in a concrete container that has a fast-draining soil mix.

Walters Gardens, Inc. ‘Color Guard’

Terra Nova Nurseries, Inc. ‘Color Guard’ displays impressive winter interest as the foliage is tinged rosy pink during cold weather.

Eric Hofley / Michigan Gardener While yuccas are mostly known for their distinctive foliage, their flowers look beautiful against a green background.

Walters Gardens, Inc. Eric Hofley / Michigan Gardener Use yuccas like this ‘Color Guard’ in mixed borders with Terra Nova Nurseries, Inc. ‘Bright Edge’ perennials and small shrubs. Yucca rostrata ‘Sapphire Skies’ sports powder blue leaves. MichiganGardener a August2010 17 plant focus

Yucca

Yucca (Yucca filamentosa) is one of the most centered leaves edged in green. The result is durable perennials for the garden. Plants are electric in the summer garden. In winter and hardy to zone 4, allowing them to overwin- during cool weather, the yellow stripe blushes ter effortlessly in upper and lower Michigan. rose. The 24-inch tall plants are exceptional They also thrive in southern climates such as as specimens and may even be used in spring Florida and Texas. Their Southwestern look containers as a spike replacement. is unmistakable in any landscape where they ‘Bright Edge’ is quite similar but with can live for decades with no maintenance green-centered leaves edged with creamy whatsoever. The long, pointed leaves are usu- gold. It grows to a height of 18 inches with ally green, radiating from the ground wher- flowers only 3 feet tall. Although ‘Color Guard’ ever the roots are established. Leaf tips are and ‘Bright Edge’ are slightly smaller than the dangerously pointed and justify the common species, their flowers, durability, drought tol- name “Adam’s needle.” The deer-resistant erance, and deer resistance are the same. foliage persists all winter long, thus giving The newest hardy yucca on the market is yucca its “evergreen” designation. Yucca rostrata ‘Sapphire Skies.’ This powder Other evergreens such as boxwood, yews, blue-leafed selection has non-threatening azaleas, junipers, spruce, etc. provide a com- flexible foliage and is hardy to zone 5. ‘Sap- pletely different texture. And although yuc- phire Skies’ is best positioned in full sun with cas can produce flowers, it is the unusual well-drained soil. Its real claim to fame is that texture of the leaves that makes them most this is a trunk-forming species; experts say useful in the landscape. Yucca foliage perfect- that in time, the blue foliage will protrude ly exemplifies coarse foliage. It is this coarse from the top of a true trunk. Being such a foliage that contrasts very well with more new variety, I have yet to learn of a Michigan- bold-leafed plants such as hostas, ligularias, grown specimen beginning its journey into viburnums or fine-leafed plants such as juni- “trunkhood.” But like most gardeners, I will pers, ferns, and astilbes. Like other “shrubs,” keep an optimistic, open mind until experi- Walters Gardens, Inc. yuccas can be planted in mass where space ence proves that the experts are incorrect. The bold leaves of the yucca ‘Bright Edge’ combine well with permits. They also serve well as a single spec- Yuccas will eventually produce clumps the fine foliage of this ornamental grass Pennisetum( ). imen in the rock garden or perennial border. that may require dividing, moving, or per- Yuccas will typically form coarse clumps haps elimination. I have often heard of at- 2-1/2 feet tall and wide in full sun or even tempts to relocate or eliminate a yucca that Yucca, Adam’s Needle full shade. They will tolerate all kinds of soil initially seemed successful. However, the re- Botanical name: Yucca(YUK-uh) Light: Fulltopartsun except for those that remain water-saturated maining roots typically produce young yucca Plant type: Evergreenperennial Soil: Average,well-drained for long stretches of time. Mature plants are shoots that develop into mature clumps. To drought tolerant and will even tolerate com- completely eradicate a yucca, one typically Plant size: 18-36inchestallandwide, Uses: Specimen,textural petition from tree roots in either sun or shade. has to remove roots repeatedly or maybe even dependingonvariety contrast,architectural Yuccas grown in a sunnier position will pro- apply herbicide… a few times. Needless to say, Habit: Clumpingcrown plant.Useinamixed duce creamy white flower stalks that range yuccas are persistent. Hardiness: Zone4/5 borderwithperennialsand smallshrubs. from 3 to 8 feet tall in July and August. The The unique texture that yucca provides Flower color: Creamywhite spent stalks should be removed at the base may not fit into every landscape. But Adam’s Remarks: Droughttolerantplant.Soil Flower size: 1-2incheslong,bell-like; when the flowers have finished, as the fruiting needle can be much more than just a textural mustbewell-drainedin flowerstalkextendsafew stalk is unsightly and will persist for years. plant. Its ability to survive in a wide range of bothsummerandwinter. feetabovethefoliage Although the all- soils, climates, and exposures Goodwinterinterestas green Adam’s needle is with virtually no mainte- Bloom period: Summer leavesbecometingedwith useful as a textural plant, nance makes it one of the most Leaf color: Green,yellow-green arosypink.Leavesare there are other varieties adaptable plants available. variegation,blue-green sharp;usecautionwith with more striking foli- George Leaf size: Upto24incheslong,1to childreninthearea. age. ‘Color Guard’ has Papadelis George Papadelis is the owner of 1-1/2incheswide glowing, canary yellow- Telly’s Greenhouse in Troy, MI.