Hosta
Encyclopedia
Hosta is a genus
of about 23–45 species
of lily-like plants in the family
Asparagaceae
, subfamily Agavoideae, native to northeast Asia
. They have been placed in their own family, Hostaceae (or Funkiaceae); like many 'lilioid monocot
s', they were once classified in the Liliaceae
. The scientific name is also used as the common name
; in the past they were also sometimes called the Corfu Lily, the Day Lily, or the Plantain lily, but these terms are now obsolete. The name Hosta is in honor of the Austrian botanist Nicholas Thomas Host. The Japanese
name Giboshi is also used in English to a small extent. The rejected generic name Funkia, also used as a common name, can be found in some older literature.
perennial plant
s, growing from rhizome
s or stolon
s, with broad lanceolate or ovate leaves
varying widely in size by species from 1–18 in (3–45 cm) long and 0.75–12 in (2–30 cm) broad. Variation among the numerous cultivars is even greater, with clumps ranging from less than 4 in (10 cm) across and 3 in (8 cm) high to more than 6 ft (200 cm) across and 4 ft (130 cm) high. Leaf color in wild species is typically green, although some species (e.g., H. sieboldiana) are known for a glaucous waxy leaf coating that gives a blue appearance to the leaf. Some species have a glaucous white coating covering the underside of the leaves. Natural mutations of native species are known with yellow-green ("gold") colored leaves or with leaf variegation (either white/cream or yellowish edges or centers). Variegated plants very often give rise to "sports" that are the result of the reshuffling of cell layers during bud formation, producing foliage with mixed pigment sections. In seedlings variegation is generally maternally derived by chloroplast transfer and is not a genetically inheritable trait.
The flower
s are produced on erect scape
s, general taller than the leaf mound, that end in terminal racemes. The individual flowers are usually pendulous, 0.75–2 in (2–5 cm) long, with six tepal
s, white, lavender, or violet in color and usually scentless. The only strongly fragrant species is Hosta plantaginea, which has white flowers up to 4 in (10 cm) long; it is also unusual in that the flowers open in the evening and close by morning. This species blooms in late summer and is sometimes known as "August Lily".
. Interspecific hybridization occurs since all the species have the same chromosome
number (2n = 2x = 60); except H. ventricosa which is a natural tetraploid that sets seed through apomixis
. Many Hosta formerly described as species taxonomically, have been reduced to cultivar
s; these often have their names conserved, and retain Latin names which resemble species names (e.g., H. 'Fortunei' ).
, most of the species that provide the modern shade garden plants were introduced from Japan
to Europe by Philipp Franz von Siebold
in the mid-19th century. Newer species have been discovered on the Korea
n peninsula as well.
Hostas are widely cultivated ground cover plants, particularly useful in the garden as shade-tolerant plants. Hybridization within and among species and cultivars has produced numerous cultivar
s, with over 3000 registered and named varieties, and perhaps as many more that are not yet registered with the American Hosta Society. Cultivars with golden- or white-variegated
leaves are especially prized. Popular cultivars include 'Francee' (green leaves with white edges), 'Gold Standard' (yellow leaves with green edges, discovered by Pauline Banyai) 'Undulata
' (green leaves with white centers), 'June' (blue-green leaves with creamy centers), and 'Sum and Substance' (a huge plant with chartreuse-yellow leaves). Newer, fragrant cultivars such as 'Guacamole' are also popular. Pictures of hosta species and cultivars, along with other information, may be found at http://www.hostalibrary.org.
The American Hosta Society and the British Hosta and Hemerocallis Society support Hosta Display Gardens, often within botanical garden
s.
Hostas are edible by humans and are called "urui" in Japan
where they are commonly consumed. The parts eaten and the manner of preparation differ depending on the species; in some cases it is the shoots, others the leaf petiole, others the whole leaf. Younger parts are generally preferred as being more tender than older parts. The flowers are also edible. Descriptions (from a Western perspective) of the edibility of several species are at Plants for a Future.
Hostas are notoriously a favourite food for deer
, slug
s and snail
s, which commonly cause extensive damage to hosta collections in gardens. Poisoned baits using either metaldehyde or the safer iron phosphate work well for the latter, but require repeated applications. Deer control tends to be variable, as anything other than fencing tends to work for a few years then ceases to work as they become accustomed to it.
Foliar nematodes
, which leave streaks of dead tissue between veins, have become an increasing problem since changes in attitudes about pesticides since the mid-1990s in many countries have caused a resurgence in this once-controlled pest. There are no effective means for eliminating nematodes in the garden, although they can be controlled to the point where little or no symptoms are seen.
A potexvirus called Hosta Virus X has become common recently, and plants that are infected must be destroyed as the disease can be transmitted from plant to plant by contaminated sap. Symptoms include dark green "ink bleed" marks in the veins of yellow-colored leaves, and/or tissue collapse between veins. It can take years for symptoms to show, so symptomless plants in infected batches should also be considered infected.
Otherwise they are generally easy and long-lived garden plants, relatively disease free, requiring little care other than watering and some fertilizer to enhance growth. Some varieties are more difficult to grow, as can be expected with 5,000+ cultivars, but most are easy enough for beginners.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of about 23–45 species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of lily-like plants in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Asparagaceae
Asparagaceae
Asparagaceae is the botanical name of a family of flowering plants, placed in the order Asparagales of the monocots.In earlier classification systems, the species involved were often treated as belonging to the family Liliaceae...
, subfamily Agavoideae, native to northeast Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
. They have been placed in their own family, Hostaceae (or Funkiaceae); like many 'lilioid monocot
Lilioid monocot
Lilioid monocots or lilioids is an informal name used for a grade of five monocot orders in which the majority of species have flowers with relatively large, coloured tepals, broadly similar to those of lilies...
s', they were once classified in the Liliaceae
Liliaceae
The Liliaceae, or the lily family, is a family of monocotyledons in the order Liliales. Plants in this family have linear leaves, mostly with parallel veins but with several having net venation , and flower arranged in threes. Several have bulbs, while others have rhizomes...
. The scientific name is also used as the common name
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
; in the past they were also sometimes called the Corfu Lily, the Day Lily, or the Plantain lily, but these terms are now obsolete. The name Hosta is in honor of the Austrian botanist Nicholas Thomas Host. The Japanese
Japanese language
is a language spoken by over 130 million people in Japan and in Japanese emigrant communities. It is a member of the Japonic language family, which has a number of proposed relationships with other languages, none of which has gained wide acceptance among historical linguists .Japanese is an...
name Giboshi is also used in English to a small extent. The rejected generic name Funkia, also used as a common name, can be found in some older literature.
Description
Hostas are herbaceousHerbaceous
A herbaceous plant is a plant that has leaves and stems that die down at the end of the growing season to the soil level. They have no persistent woody stem above ground...
perennial plant
Perennial plant
A perennial plant or simply perennial is a plant that lives for more than two years. The term is often used to differentiate a plant from shorter lived annuals and biennials. The term is sometimes misused by commercial gardeners or horticulturalists to describe only herbaceous perennials...
s, growing from rhizome
Rhizome
In botany and dendrology, a rhizome is a characteristically horizontal stem of a plant that is usually found underground, often sending out roots and shoots from its nodes...
s or stolon
Stolon
In biology, stolons are horizontal connections between organisms. They may be part of the organism, or of its skeleton; typically, animal stolons are external skeletons.-In botany:...
s, with broad lanceolate or ovate leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
varying widely in size by species from 1–18 in (3–45 cm) long and 0.75–12 in (2–30 cm) broad. Variation among the numerous cultivars is even greater, with clumps ranging from less than 4 in (10 cm) across and 3 in (8 cm) high to more than 6 ft (200 cm) across and 4 ft (130 cm) high. Leaf color in wild species is typically green, although some species (e.g., H. sieboldiana) are known for a glaucous waxy leaf coating that gives a blue appearance to the leaf. Some species have a glaucous white coating covering the underside of the leaves. Natural mutations of native species are known with yellow-green ("gold") colored leaves or with leaf variegation (either white/cream or yellowish edges or centers). Variegated plants very often give rise to "sports" that are the result of the reshuffling of cell layers during bud formation, producing foliage with mixed pigment sections. In seedlings variegation is generally maternally derived by chloroplast transfer and is not a genetically inheritable trait.
The flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s are produced on erect scape
Scape (botany)
In botany, scapes are leafless flowering stems that rise from the ground. Scapes can have a single flower or many flowers, depending on the species....
s, general taller than the leaf mound, that end in terminal racemes. The individual flowers are usually pendulous, 0.75–2 in (2–5 cm) long, with six tepal
Tepal
Tepals are elements of the perianth, or outer part of a flower, which include the petals or sepals. The term tepal is more often applied specifically when all segments of the perianth are of similar shape and color, or undifferentiated, which is called perigone...
s, white, lavender, or violet in color and usually scentless. The only strongly fragrant species is Hosta plantaginea, which has white flowers up to 4 in (10 cm) long; it is also unusual in that the flowers open in the evening and close by morning. This species blooms in late summer and is sometimes known as "August Lily".
Taxonomy
Taxonomists differ on the number of hosta species; there may be as many as 45. Accordingly, the list of species at the right may be taken loosely. The genus may be broadly divided into three subgeneraSubgenus
In biology, a subgenus is a taxonomic rank directly below genus.In zoology, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the generic name and the specific epithet: e.g. the Tiger Cowry of the Indo-Pacific, Cypraea tigris Linnaeus, which...
. Interspecific hybridization occurs since all the species have the same chromosome
Chromosome
A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...
number (2n = 2x = 60); except H. ventricosa which is a natural tetraploid that sets seed through apomixis
Apomixis
In botany, apomixis was defined by Winkler as replacement of the normal sexual reproduction by asexual reproduction, without fertilization. This definition notably does not mention meiosis...
. Many Hosta formerly described as species taxonomically, have been reduced to cultivar
Cultivar
A cultivar'Cultivar has two meanings as explained under Formal definition. When used in reference to a taxon, the word does not apply to an individual plant but to all those plants sharing the unique characteristics that define the cultivar. is a plant or group of plants selected for desirable...
s; these often have their names conserved, and retain Latin names which resemble species names (e.g., H. 'Fortunei' ).
Cultivation and uses
Though Hosta plantaginea originates in ChinaChina
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
, most of the species that provide the modern shade garden plants were introduced from Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
to Europe by Philipp Franz von Siebold
Philipp Franz von Siebold
Philipp Franz Balthasar von Siebold was a German physician and traveller. He was the first European to teach Western medicine in Japan...
in the mid-19th century. Newer species have been discovered on the Korea
Korea
Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...
n peninsula as well.
Hostas are widely cultivated ground cover plants, particularly useful in the garden as shade-tolerant plants. Hybridization within and among species and cultivars has produced numerous cultivar
Cultivar
A cultivar'Cultivar has two meanings as explained under Formal definition. When used in reference to a taxon, the word does not apply to an individual plant but to all those plants sharing the unique characteristics that define the cultivar. is a plant or group of plants selected for desirable...
s, with over 3000 registered and named varieties, and perhaps as many more that are not yet registered with the American Hosta Society. Cultivars with golden- or white-variegated
Variegation
Variegation is the appearance of differently coloured zones in the leaves, and sometimes the stems, of plants. This may be due to a number of causes...
leaves are especially prized. Popular cultivars include 'Francee' (green leaves with white edges), 'Gold Standard' (yellow leaves with green edges, discovered by Pauline Banyai) 'Undulata
Hosta undulata
Hosta 'Undulata is a cultivar of the genus Hosta, widely cultivated as ornamental plants in borders or as specimen plants. It was formerly regarded as a species under the name Hosta undulata L.H.Bailey...
' (green leaves with white centers), 'June' (blue-green leaves with creamy centers), and 'Sum and Substance' (a huge plant with chartreuse-yellow leaves). Newer, fragrant cultivars such as 'Guacamole' are also popular. Pictures of hosta species and cultivars, along with other information, may be found at http://www.hostalibrary.org.
The American Hosta Society and the British Hosta and Hemerocallis Society support Hosta Display Gardens, often within botanical garden
Botanical garden
A botanical garden The terms botanic and botanical, and garden or gardens are used more-or-less interchangeably, although the word botanic is generally reserved for the earlier, more traditional gardens. is a well-tended area displaying a wide range of plants labelled with their botanical names...
s.
Hostas are edible by humans and are called "urui" in Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
where they are commonly consumed. The parts eaten and the manner of preparation differ depending on the species; in some cases it is the shoots, others the leaf petiole, others the whole leaf. Younger parts are generally preferred as being more tender than older parts. The flowers are also edible. Descriptions (from a Western perspective) of the edibility of several species are at Plants for a Future.
Hostas are notoriously a favourite food for deer
Deer
Deer are the ruminant mammals forming the family Cervidae. Species in the Cervidae family include white-tailed deer, elk, moose, red deer, reindeer, fallow deer, roe deer and chital. Male deer of all species and female reindeer grow and shed new antlers each year...
, slug
Slug
Slug is a common name that is normally applied to any gastropod mollusc that lacks a shell, has a very reduced shell, or has a small internal shell...
s and snail
Snail
Snail is a common name applied to most of the members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word is used in its most general sense, it includes sea snails, land snails and freshwater snails. The word snail without any qualifier is however more often...
s, which commonly cause extensive damage to hosta collections in gardens. Poisoned baits using either metaldehyde or the safer iron phosphate work well for the latter, but require repeated applications. Deer control tends to be variable, as anything other than fencing tends to work for a few years then ceases to work as they become accustomed to it.
Foliar nematodes
Foliar nematodes
Foliar nematodes are plant parasitic roundworms in the genus Aphelenchoides. The three most economically important species are Aphelenchoides fragariae, A. ritzemabosi, and A. besseyi. Foliar nematodes are becoming a widespread and serious problem for the ornamental and nursery industries. A...
, which leave streaks of dead tissue between veins, have become an increasing problem since changes in attitudes about pesticides since the mid-1990s in many countries have caused a resurgence in this once-controlled pest. There are no effective means for eliminating nematodes in the garden, although they can be controlled to the point where little or no symptoms are seen.
A potexvirus called Hosta Virus X has become common recently, and plants that are infected must be destroyed as the disease can be transmitted from plant to plant by contaminated sap. Symptoms include dark green "ink bleed" marks in the veins of yellow-colored leaves, and/or tissue collapse between veins. It can take years for symptoms to show, so symptomless plants in infected batches should also be considered infected.
Otherwise they are generally easy and long-lived garden plants, relatively disease free, requiring little care other than watering and some fertilizer to enhance growth. Some varieties are more difficult to grow, as can be expected with 5,000+ cultivars, but most are easy enough for beginners.
External links
- American Hosta Society
- Hosta Library 17000 Hosta Photographs, Articles, and Hosta Auction
- Hosta Virus X, Kansas State University
- HOSTA SEED BANK (Swap of Hosta Seeds)
- HOSTAS Cubit (ID, Hybridizing, Sources databases; forums)
- Danish Hosta Society