The term, 'perennial plant', means simply that
the plant returns following severe freezes, to grow again the next year. Trees
are cold hardy tested perennials by nature, some trees that are evergreens and
do not go dormant, but merely slow down during various seasons, and other shade
trees enter dormancy and shed the leaves. Tree growth of shade trees may stop
altogether in extremely cold climates, but in the spring, will surge with buds
that open to flower and leaf out.
Great difficulties arise in assigning a plant,
'perennial', mainly because the primary determining factor, temperature range
varies from year to year; and every century extreme cold temperatures may erase
certain plant populations that have survived in areas before for decades or
sometimes even centuries. A perennial plant may be a survivor, thus a
“perennial” for a given growing area, then suddenly may become extinct in that
growing area. The USDA has constructed a zone map that reveals averages of
temperatures reached by the location in your State. This map is a nursery tool
used to predict whether a perennial will live (cold hardy) in your area.
Agaves are a diverse genus of over 200 species of
rosette, spear-like, leafed evergreen perennials. Agave typically grows as low
shrub-like plants in dry or well-drained soils of the Southern part of the U.S.
from New Jersey down to Florida, and then West to California. Many Agave
species, such as Agave americana or Agave tequilana, have sharp recurved,
protective teeth running along both sides of the blade of its semi-curved,
lance-shaped leaves, with a sharp needle-tip lance at the end. There are Agave
species, like Agave attenuata, and Agave stricta, that do not have sharp-teeth
at all, but are smooth. The color variations of Agave plants range from shades
of green, to silvery-grey, bluish-green, top yellow or white stripes, such is
the case with Agave americana 'media-picta'. The bloom of mother Agave plants
are a beautiful array of pendulent bell-shaped, creamy-white flowers soaring
high above the mother plant on a flower stem that may reach 20 feet or more for
some agave species. The bloom period of a mother Agave plant is during the
summer and the flower stalk is magnificent to behold, however, this event means
the cycle of life ends for mother Agave and begins again for her Agave
offspring. Agave plants are an excellent choice for rock gardens or well
drained soils that lend themselves well to terracotta or cement planters.
Agaves are fairly slow glowers so expect higher prices on these sunloving
garden jewels at retail garden centers. Huge specimen agaves can be quickly
delivered by semi-trucks. Recommended Agave cultivar plants are: Agave
'Victoria-Reginae'; Agave americana; Agave americana 'Marginata'; Agave
americana 'Media-Picta'; Agave angustifolia 'Marginata'; Agave attenuata
'Boutin Blue'; Agave bovicomuta; Agave celsii 'Nova'; Agave colorata; Agave
desmettiana 'Variegata'; Agave desmettiana 'Zebra Stripe'; Agave 'Felipe
Otero'; Agave franzosini; Agave geminiflora; Agave lechguilla; Agave parryii;
Agave parryii 'Compacta Variegata'; Agave potatorum 'Verschaffeltii'; Agave
pygmaea; Agave salmiana; Agave stricta 'Pueblensis'; Agave 'Shark Skin'; Agave
sisalana 'Variegata'; Agave toumeyana; and Agave tequilana 'Weberi Blue.'
The ancient Egyptians in 1500 BC grew the Aloe
for healing, and while the Pharaoh held all the Jews in captivity, aloes were
used as cosmetics and for the sacred healing power of this mysterious
perennial. The Book of John, in the New Testament Bible, John 19-39, records
that Jesus' body was wrapped in linen cloths and aloes after the corpse was
removed from the crucifiction cross before burial. Aloes are evergreen
perennial plants that grow as shub-like, climbing or tree-like plants. The aloe
plant leaves are fleshly, succulent, long tongue-shaped groups of rosettes, or
as star-patterned limbs. Most forms of the aloe, 300 species genus, have
toothed leaf blades with soft to piercing hard teeth. Aloe saponaria and Aloe
vera are the two most commonly found containerized aloes in homes and gardens.
Aloe vera plant extracts have long been used by mothers on their children for
fast relief for minor cuts and burns. Aloe saponaria is cold hardy down to
freezing temperatures and is widely grown in Southern gardens for the
beautiful, coral-colored, tubular blossoms and for the making of medicated
soap. Most aloe plants are small, 1-3 foot tall and width, however, a few
tropical aloe species, such as Aloe marlothii grow into large, 120 foot
succulent trees. Aloe plant varieties may vary enormously in color from yellow,
red to blue-greens, or to spotted or striped with random variegation.
Recommended cultivars of Aloes are: Orange Aloe.(Aloe acutissima
'antaramorensis') ,Blue Aloe (Aloe acutissima) ,Aloe aristata 'Montana' Tree
Aloe (Aloe bainsii) Aloe brevifolia Red Aloe (Aloe camronii) Climbing Aloe
(Aloe ciliaris) Kokoerbom(Aloe dichotoma) Aloe distans 'Yellow Teeth'Aloe
'Dorian Black' Aloe ellenbeckii White Aloe (Aloe glauca) Aloe kedongensis
Bergaalwyn (Aloe marlothii) Gold Tooth Aloe (Aloe nobilis) Tiger Aloe (Aloe
nobilis 'Variegata') Aloe petricola Spiral Aloe (Aloe polyphylla) Coral Aloe
(Aloe strata) SoapAloe (Aloe saponaria) Aloe traskii Medicinal Aloe (Aloe vera)
Partridge Breast (Aloe 'Variegata') Aloe verdoorniae Aloe 'White Teeth'.
Fern plants are a beautiful landscape choice or a
container perennial, because of the delicate graceful foliage. Fern plants are
native to the U.S., and found growing on every continent on the Earth. Some
ferns grow well as cold hardy plarts in some areas bordering arctic conditions.
A gardener can find a fern perennial to buy in practically any nursery or mail
order operation.
Florida tropical perennials are restricted for
growing in many States, because of the lack of cold hardy resistance. Some
gardeners prefer to plant Florida perennials in greenhouses, or to grow as an
annual. Many recommended plants are: Desert Rose, Adenium obesum; Allamanda
cathartica; Giant Yellow Shrimp, Barleria micans; Hallmark, Bulbine fruiticasa;
Clerodendrum ugandense; Bleeding Hearts, Clerodendrum thomsoniae; Bat Faced
Heather, Cupha ilvea; Sapphire Showers, Duranta erecta; Euryops; Bolivian
Sunset, Gloxina sylvatica; Iochroma cyaneum; Jatropha integerrima; Ixora;
Lantana camara; Orthosiphon stamineus; Pentas; Russelia equisetiformis;
Russelia equisetiformis aureus; Stachytarpheta urticifolia; Stachytarpheta mutabilis.
Flowering Vine perennials grow fast to cover
fences, lattices, walls, and not only offer rewards of flowers, but many
interesting flowers in colors of red, blue, white, pink, and yellow. If planted
and grown in the sun, the flowering vines require little care of vine
maintenance. Recommended flowering vines to plant are Coral Vine, Antigonon
leptopus; White Coral Vine, Antigonon leptopus 'Alba'; Jekyll Island Vine,
Bignonia capreolata; Tangering Beauty, Bignonia capreolata; Night Blooming
Jasmine, Cestrum Nocturnum; Bleeding Hearts, Clerodendron thomsoniae; Lavender
Trumpet Vine, Clytostoma callistegoides; Carolina Jasmine, Gelsemium
sempervirens; Heart Vine, Ipomoea batatas; Chinese Jasmine, Jasminum
polyanthum; Brazilian Firecracker Vine, Manettia inflata; Mailbox Plant,
Mandevilla x Amblilis; Red Mandevilla, Mandevilla sanderi; Peaches and Cream,
Mandevilla 'Peaches and Cream'; Pink Mandevilla, Mandevilla splendens; White
Passion Vine, Passiflora; Blue Passion Vine, Passiflora x Alato-Caerulea; Red
Passion Flower, Passiflora coccinea; Lady Banks Rose, Rosa banksiae; Blue Glory
Vine, Thunbergia battiscombei; White Sky Vine; Thunbergia grandiflora;
Confederate Jasmine, Trachelospermum jasminoides; Blue Wisteria, Wisteria
sinensis; White Wisteria, Wisteria sinensis 'Alba';
Groundcover perennial plants are beautifully
colored and fast growing, to keep soil erosion under control. Recommended
groundcover plants are: Ajuga reptans 'Burgundy Glow', Burgundy Glow; Allium
tuberosum, Society Garlic; Arachis glabrata, Perennial Peanut; Ardisia japonica
'Variegata', Ardisia japonica 'Variegata'; Aspidistra elatior, Cast Iron Plant;
Aspidistra elatior 'Variegata', Aspidistra elatior 'Variegata'; Apsidistra
lurida 'Milky Way', Apsidistra lurida 'Milky Way'; Asystasia gangetica, Ganges
Primrose; Curculigo capitulata, Palm Grass; Ficus repens 'Variegata', Creeping
Fig Vine; Ficus repens 'Variegata', Ficus repens 'Variegata'; Houttuynia
cordata 'Chameleon', Chameleon; Liriope; Liriope muscari 'Big Blue', Border Grass;
Liriope muscari 'Royal Purple', Liriope muscari 'Royal Purple'; Liriope muscari
'Super Green Giant'; Liriope muscari 'Variegata'; Liriope muscari 'Silver
Dragon'; Lysimachia congestiflora 'Eco Dark Satin', Golden Globes; Ophiopogon
intermedius 'Aztec'; Ophiopogon japonicus nana, Dwarf Mondo Grass; Ophiopogon
planiscapus 'Ebony Knight', Black Mondo; Persicaria capitatum, Jump Seed;
Persicaria microcephala, Red Dragon; Setcreasea pallida, Purple Heart;
Setcreasea pallida, Pale Puma; Pseuderanthemum alatum, Chocolate Soldiers;
Rubus calycinoides, Emerald Carpet; Scuttelaria longifolia, Red Fountain Sage;
Spilanthese oleracea, Eyeball Plant / Toothpaste Plant; Trachelospermum
asiaticum, Asiatic Jasmine; Tulbaghia fragrans, White Fragrant Garlic;
Tulbaghia violacea, Society Garlic; Tulbaghia violacea 'Tricolor', Tricolor,
Society Garlic; Vinca major 'Maculata', Periwinkle; Vinca major 'Variegata',
Periwinkle; Vinca major 'Wojo's Gem'.
Herbacious perennial plants freeze during the
winter, but return in the following spring to produce flowers of many colors
and rare forms. Recommended cultivars are: Bee Balm, Monarda didyma 'Jacob
Cline'; Blue Butterfly Flower, Clerodendrum ugandense; Blue Woodland Phlox,
Phlox divaricata; Brunfelsia Pauciflora; Buckeye, Red, Aesculus pavia;
Butterfly Bush, Buddleia lindleyana; Cestrum aurantiacum; Cigarette Plant,
Cuphea micropetala; Clerodendrum bungeii; Cone Flower, Echinacea paradoxa;
Cuphea 'Allyson'; Devil Star Lily, Clerodendrum puniculatum; Echinacea 'White
Swan'; Echinacea purpurea; Firebush, Hamelia patens; Flowering Maple, Abutilion
x hybridrum; Gaillardia 'Pin Wheel'; Lestrum fasciculatum 'Newellii'; Liatris
spicata 'Blazing Stars'; Liatris spicata 'Floristan'; Lions Head, Leonitus
leonarus; Obediant Plant, Physostegia virginiana; Orange Shrimp Plant, Justicia
ovata; Orange Tongue Plant, Justicia leonardii; Phlox maculata 'Alpha'; Pink
Tongues, Justicia carnea; Platycodon grandiflora; Plumbago auriculata 'Monott'
PP7822; Princess Flower, Tibouchina urvillenana; Purple Butterfly Bush,
Buddleia davidii 'Lochinch'; Red Cigar Plant, Sinningia sellovii;Red Prince,
Weigela florida; Red Shrimp Plant, Justicia brandegeana 'Red'; Mouth of
Hollywood, Rehmannia Elata; Rudbeckia hirta 'Becky Mix'; Ruellia brittoniana
'Katie'; Ruellia elegans; Scarlet Butterfly Lily, Odontonema cuspidatum; Shasta
Daisy, Leucanthemum x superbum 'Alaska'; Shower of Gold Shrub, Galphimia
glauca; Tecoma stans 'Yellow Bells'; Turks Cap, Malvaviscus drummondi; White
Tongues, Justicia carnea; Yellow Creeping Jenny, Lysimachia nummularia 'Aurea';
Yellow Shrimp Plant, Justicia brandegeana 'Yellow'; Yellow Tongue Plant,
Justicia aura.
Yucca is a genus of evergreen plants, with
approximately 40 species that grow in dry, desert-like areas. However, this is
a common misconception, because members of the Yucca family can be found
growing in 30 of the States in America, from New Jersey, down to Florida, and
west to California. Yuccas can be grown as small shrubs or yucca trees, up to
30 feet tall, depending upon the yucca species. Yucca has lance-shaped leaves
growing in a rosette pattern, on a woody stem or trunk-like frame. Yucca plants
may vary dramatically in color from shades of green, to white or yellow
stripes, to blue-green hues, as with Yucca rostrata, a jewel for any garden.
Most yucca plants are stiff and sharp pointed, like the Spanish Bayonet (Yucca
aloifolia), while some yuccas have flexable soft leaves, such as Golden Garland
Yucca (Yucca flaccida). The flower blooms of yucca grow in summer, and develop
into a beautiful, creamy-white pendulum of bell-shaped flowers that tower 8
feet above the mother plant. Yuccas are very adaptable and are among the oldest
living trees in the world. The Joshua Tree (Yucca brevifolia), Yucca
filimentosa (Bear Grass or Adam's Needle) is among the most cold-hardy and
widely grown varieties. The strong, stringy filament (fiber), that run a course
from the needle tip, down the margin of the leaf, was used by native Americans
for making into garments and possibly the treating of war wounds. The roots of
Yucca were also used to make soap. The primary use for yucca plants in todays
landscapes are for their ornamental beauty, like we find in Yucca flaccida
'Golden Sword', in terracotta pots or in ground landscape plantings. Some people
use Yucca aloifolia 'Spanish Bayonet', Yucca treculeana 'Spanish Dagger', or
even Yucca brevifolia 'Joshua Tree', as security hedges for their beautiful and
exotically bazaar, stiff leaves, hence the nickname, “Burlars' Nightmare.”
Yucca plants are typicall sunlovers, growing in well drained soils, but are
adaptive and often grow faster in moderately moist areas, such as the
Southeastern U.S.. Recommended yucca cultivar plants are: Yucca aloifolia;
Yucca brevifolia; Bear Grass, Yucca filamentos; Bright Edge, Yucca filamentosa;
Golden Garland, Yucca flaccida; Golden Sword, Yucca flaccida; Ivory Tower,
Yucca flaccida; Variegata, Yucca flaccida; Silverstar, Yucca elephantippes;
Soft Leaf Yucca, Yucca recurvifolia; Spanish Dagger, Yucca treculeana; Rigida, Yucca
rostrata; Linearis, Yucca rostrata; HesperYucca paviflora; Cordyline 'Baueri.'
By: Pat Malcolm -
