
Botanical/Latin
Yucca
Pronunciation
yuk-a
Common Name
Adam's Needle Yucca
Hardiness zone range
4
General Comments
Wonderful, stately evergreens with huge, fragrant, ivory-white, flower panicles and marvelous, sword-like leaves that spread outwards from a basal rosette to give the whole plant a special sculptural or architectural quality.
Light Preference
Full Sun
Culture & Care
They thrive best in reasonably
fertile soils that are well-drained and have the
capacity to retain moisture in dry weather, so
improving the site at planting time by
incorporating extra organic matter (peat, planting
compost, etc.) into the surrounding soil will
encourage good vigorous growth and plenty of
luxuriant foliage. They are reliable and very easy
to grow on most sites, providing they have good
drainage. Under no circumstances will they
tolerate poor drainage or waterlogged conditions;
on the other hand, once established, they are
tolerant of poor soils, variation in pH levels,
compacted soils, heat, drought, and even winter
salt spray. They are seldom attacked by any
serious pests or diseases, and the only
maintenance that is required is to occasionally
remove old leaves and the flowering stalk after
flowering to prevent the formation of unwanted
seeds. Choose the site carefully because once they
become established the deep, tuberous taproots
can be difficult to remove, with portions often
persisting to sprout and re-emerge.
Uses
The exotic, desert-like
appearance makes them ideal for beds around
patios, decks, and swimming pools, and other sun
drenched positions like sloping banks and
hillsides. They are great in containers, raised
beds, rock gardens, gravel gardens, and xerophytic
gardens where the soil is light, rocky, or sandy,
and heat and drought tolerance is a priority. They
form bold, dramatic clumps of spiky foliage and
tall, sweetly, night-scented, flower stems, so
they are ideal as evergreen accent plants to
create focal points in borders, island beds, or
framing entranceways, steps, and pathways. They
can be used as single specimens in perennial beds
or grouped in larger numbers where the massed
effect is stunning. The evergreen foliage lasts
well in cut flower arrangements, and the enormous
flower heads are incredible for placing in large
arrangements to make dramatic impact in large
rooms and entrance areas.
Background
The botanical name is easy to
remember because it sounds rather unflattering. It
actually comes from Iucca, a Caribbean name for
the root of Manihot esculenta (which is used for
making cassava and tapioca); the swollen "toes"
resemble those of this tender, tropical food
plant, and, when the first plants were introduced
around 1550, the herbalists were confused and
misidentified it. By the time Linnaeus and other
botanists correctly identified it as a completely
different plant, the name was firmly established,
so the genus became known as Yucca. They are
native to southern parts of North America, Central
America, and the West Indies. Only a few of the 40
or so species are suitable for our gardening
zones, and, of these, the most commonly
encountered is Yucca filamentosa and its variants.
It makes dense, slowly spreading, evergreen
clumps of grayish-green, sword-like leaves with
curly, thread-like filaments that give rise to the
species name, filamentos. In early to mid summer,
they produce sturdy, 6-8 feet tall spikes that are
loaded with numerous, ivory white, waxy,
bell-shaped flowers, all hanging downwards from
side growths to look like chandeliers on stems.
These huge flower panicles are very impressive,
providing structure and height to beds and
borders, and, when they are seen standing proudly
above the marvelous architectural foliage, the
combined effect is stunning. Our favorite is the
variegated form, Yucca 'Golden Sword'. It is a
superb garden plant with green-margined,
sword-like leaves that have a broad, golden-yellow
center in each leaf blade. Because they are less
rigid than some of the other species, they often
reflex at the tips to hang downwards to make an
eye-catching foliage display, especially in
autumn, winter, and spring. The clumps get to
about 3 - 4 feet high with summer flower stalks
that are an amazing 3 to 8 feet tall with
beautiful, ivory-white, bell-shaped flowers. It
has received an Award of Garden Merit from the
Royal Horticultural Society in Great
Britain.
Splendor Suggestions
The variegated forms are not
quite as hardy as the usual green forms;
therefore, if you garden in the colder parts of
Zone 4, think about putting down an extra layer of
insulating mulch in late autumn or early winter. A
good deep layer of 2-4 inches will help to protect
the crown and roots during the worst part of the
winter. In spring, when the temperatures start to
rise, it should be raked back and spread over a
greater area to help retain soil moisture and
reduce weed competition. Alternative materials
like straw bales, proprietary insulating
materials, even old carpets can be used, but since
these can be unsightly and a host for vermin, we
find that mulch (especially hardwood mulch) is the
most effective and attractive option.
Companion Plants
They look great springing up out
of low spreading ground cover, and are often used
in perennial plantings with Sedums, Delospermas,
Dianthus, Coreopsis, Liriope, and silvery carpets
of Stachys (Lambs Ears), or with low growing,
woody partners like Genista, Cotoneasters,
Arctostaphylos, Ilex 'Helleri', Junipers, and
Microbiota decussata, where the spiky leaves and
tall spires sharpen up the soft foliage giving the
plantings a strong, vertical emphasis. They are
sun lovers and are tremendously useful in
situations where the site is hot and dry, reveling
in the hot summer sun with drought tolerant Vitex
(Chastetree), Lespedeza 'Gibraltar', Cytisus
(Scotch Broom), and taller growing perennials like
Achilleas, Agastache, Gauras, Echinaceas, and
Rudbeckias (Black Eyed Susan). If the soil is
reasonably fertile and able to retain some
moisture, Gypsophila (Baby's Breath) Heucheras,
Perovskia, and Salvias (ornamental sage) will give
nice contrasts and plenty of supporting color.
Flowering shrubs like Caryopteris, Lagerstroemias,
Buddleias, Hibiscus, and Hydrangeas will enjoy the
same conditions and provide lots of summer color.
Where the space only permits a few plants, think
about trying them with Lavenders, Scabiosa 'Pink
Mist and 'Butterfly Blue', Asters, and
Stokesias.