This is the term
used for a "cultivated variety" of a plant. These
names are written in
a format that has a single apostrophe ' before and after the
name. Cultivars are generally plants that have been propagated
asexually (not by seed) so that each plant of a certain
is the same as every other plant with that name. An example would be
Hosta 'Sum and Substance'.
The names of cultivars must fit certain standards set up
by an international committee on plant names. In hostas,
unfortunately, there are several instances where
different plants have been given the same name. If one
of them is registered with the AHS, that plant is the
"official" hosta of that name. Any other, non-registered
hostas of the same name need to be renamed to avoid
Unfortunately, outdated or incorrect names may appear on
plant labels or in books so we have included cross
references to dozens of "Duplicate Name" hostas in our
the AHS, there are five official size categories for hostas
including Giant, Large, Medium, Small and Miniature.
In some information sources, actual measurements are
provided for the hosta clump's height and spread while in others, terms such as "medium to large"
are used and needed to be interpreted to fit one of the 5
Remember that sizes are based on physical measurements
of individual plants at one point in time. Unfortunately, sometimes that may
be based on measuring only one plant which may not be
"typical" or it may be an immature plant that has
growing to do in future seasons. So, you are likely to
encounter some variance in your hostas compared with the
listed size in catalogs and websites. Fortunately, this
should not be a major factor.
There are 3
official "base" colors which may be applied to
describe hosta leaves. A base color is one
that covers 60% or more of the surface of the leaf. Base
colors include blue-green (commonly called blue), green
(ranging from chartreuse to dark green) and
yellow (including so-called gold colors).
A few highly variegated cultivars have the
color white covering 60% of the leaf, however, white is not
considered one of the base colors.
variegation occurs due to either the complete or partial
absence of the green molecule,
chlorophyll, in the plant's tissue. Variegation expresses itself in shades of white, yellow
or various intensities of green or blue-green. There are three locations where variegation commonly
in hosta leaves including:
Variegation - This is the lack of
chlorophyll and presence of an alternate color along the
outside edge of
the leaf blade. It can range from a pencil thin strip to a very
wide pattern covering up to 40% of the leaf surface.
Variegation aka Medio - In this case, the
center of the leaf is a different color from the true base
color (green, blue-green or yellow). In some
plants, the white medial variegation may actually take up
more than the 40% of the leaf surface.
Variegation aka Splashed - These
plants have randomly occurring streaks of different colors
spread throughout the base color. We sometimes use the term "speckles"
when small areas of yellow, white and light green appear in
the leaf. Streaked variegation is considered the least
"stable" form and plants often revert to either the original
base color or to a marginal or medial variegation. These
plants are valued as breeding plants by hybridizers. More...
category fits a particular hosta is not always easy. We
tried to base the variegation type on the location of
the chlorophyll influenced base colors; green and
blue-green. For instance if the center of the leaf is
yellow with a relatively narrow band of green in the
margin, is it a yellow medial (center) variegation or
green marginal variegation? We would call it yellow
medial variegation because the lack of chlorophyll is
the basis of variegation.
There are several
colors that may appear in contrast to the base color of a
variegated hosta leaf. These would include yellow (light
gold), white (which includes pure white, near white and
cream colored), green (usually a lighter or darker shade
than the base color) and blue-green.
New hostas are created
or occur naturally in several ways including:
Hybrids - A hybrid is the result of
transferring the pollen from the stamen of a flower to the
pistil (egg) of that
same flower (self-pollination) or the flower of a different hosta
(cross or open-pollination). This may be
the result of a conscious manipulation by a hybridizer or a
"seedling selection" where bees did the transfer
and the actual pollen parent plant cannot be
When a cross is listed it is in the format: Pod Parent
(Mother) × Pollen Parent (Father). Thus a cross of H.
'Blue' × H. 'Green' means that the seeds were borne on H. 'Blue'
and H. 'Green' provided the pollen to fertilize them. If a
plant is said to be a hybrid but only one plant is listed,
it is the mother plant which bore the seeds and the pollen
parent is unknown.
Sports - This describes the
more or less "spontaneous"
change of a part of a plant which then displays different
characteristics from the rest of the mother plant. Such hostas may be the
product of so-called "sport
fishing" where a person discovers that one or more divisions
of a hosta have
mutated in the garden or nursery. We use the term
"Nat-Sport" in our database to differentiate between
this type and sports that
originated in tissue culture.
TC Sports - This type of sport occurs during
the tissue culture (TC) propagation of hostas. Since various
growth hormones are used in the TC process and very large
numbers of plants (clones) are produced in a short period of time,
a higher percentage of sports occur than
would be the case in the garden setting. Some of these sports are
unique enough to warrant introduction as new cultivars. In
recent decades, a large percentage of the new variegated
cultivars have come from TC labs.
Unknown - Sometimes the exact
origin of a cultivar cannot be determined. Someone just
"found" a plant in his or her garden or the circumstances of the origination
are long forgotten or were never recorded. Hosta experts might guess at the background of a
based on the known characteristics of certain species or
breeding plants. However, unless the mother and/or
father are named cultivars, we have placed such plants in
the "Unknown" category in our database.
flowers generally range in color from white to near-white to various shades of
lavender and purple. Some blossoms have stripes on them or translucent edges on the tepals (hostas have tepals
rather than petals). We try to
list the base color of the flower in our database.
Unfortunately, for some reason, even when a hosta is
registered with the AHS, information on flower color and
season is often omitted.
BTW - There are reports from
Japan of hostas with yellow flowers...stay tuned. Also,
many hybridizers are attempting to breed hostas with
various shades of red in their blooms. More...
This refers to the
approximate timeframe in which flowers are borne on a
particular hosta cultivar or species. Generally, bloom times are given in
a range of calendar dates but actual flowering time may vary by garden location
(north vs south) and type of growing season.
The registration form
lists Before June 1, 6/1 to 7/15, 7/15 to 8/15, 8/15 to
10/1 and After 10/1. Unfortunately, many hostas are
described as flowering in "July" or "early August" which
does no fit neatly into the official registration dates so
we try to fit them in to the standard dates.
Based on the information
sources we enter bloom dates as June, June into July,
July, July into August, August, August into September,
September and September into October.
originators are asked to list specific bloom dates,
it might be just as useful to think in terms of early, mid
or late season blooming rather than to expect a plant to
bloom the last week of June every year. Oh, well.
This is the
year in which the cultivar was accepted for
by The American Hosta Society.
Each year, the AHS publishes a document that announces all the
cultivars that completed registration during
the previous calendar year. The release of this document completes
the official registration process. For example, registration
forms completed in 2010 are not truly registered until the
publication is issued sometime in 2011.
Unfortunately, for a
variety of reasons, a fairly large percentage of new (and
old) hosta cultivars are
not registered with AHS.
These are signified by an "NR" in this column.
This column designates
the people or entity involved with the origination and/or
registration of a new
hosta cultivar. Generally the names listed fall into two
Originators are those
people or enterprises involved in the "creation" of the
cultivar. These are the ones who hybridized, selected or
discovered a new plant as a sport or seedling.
are the people or businesses who registered the cultivar with
the AHS. In a large number of cases, one person or entity is both the
originator and registrant. However, in others, it can be two
or more different names.
For older, "historic" cultivars which were
introduced before registration became available, another person
may have completed the process on behalf of the now deceased
originator. Some plants that originated outside the U.S.
have also been handled in this manner. For example,
has registered many, many cultivars on behalf of other
originators for a variety of reasons.
Also, The American
Hosta Society itself has registered many cultivars
on behalf of some of the early pioneers of the hosta
world. So "AHS" may appear as the source of hosta
cultivars although the organization has not actually
originated any hostas.
BTW - The registration
process also allows for recognizing the person who
hosta cultivar and the person or business who
into commerce. We do not list these names in our database
but, if you are interested, they will appear on the official