Q. Perennials
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Standards for Plant Grades
I.    The horticultural publication of record issued by the Perennial Plant Association should be our guideline for nomenclature.  References         include:

A.    Naamlijst Van Vaste Planten
B.    Index Hortensis Volume I Perennials
C.    Royal Horticultural Society Dictionary of Plants
D.     Hortus III

II.    Currently accepted scientific names should be used in all instances instead of common names.

III.     Wholesale catalogues should include propagation methods, the code being:

A.    C     -     Cuttings
B.    D     -     Division
C.    S     -     Seed
D.    TC    -     Tissue Culture
E.    G     -     Grafted
F.    RC    -     Rooted Cuttings
G.    TC*    -     Plant division originated in TC

IV.    If a plant is originated by tissue culture, that designation should be continued even if the plant is later propagated by division.

V.    Glossary
    The following are examples of terms used to describe some propagaules and the container size suggested for each category.

A.    Astilbe - “Eye” is the correct term to describe an Astilbe division.

  1. 1-2 eye division - 10 - 12 cm pot size
  2. 2-3 eye division - 11.5 - 15 cm pot size, or Field Clump (FC)
  3. 3-5 eye division - #1 to #2 pot size,or FC
  4. 5 eye and larger - #2 pot size, or FC

B.    Dicentra - Bleeding Heart - “Eye” is the correct term to describe a Dicentra division.

1.    1-2 eye division - 10 cm pot size
2.    2-3 eye division - 11.5 cm pot size, or FC
3.    3-5 eye division - #1 to #2 pot size, or FC
4.    5 eye and larger - #2 pot size, or FC

C.    Hemerocallis - Daylily - “Fan” is the correct term to describe a daylily division. “Eye” is incorrect.

1.    Divisions:
    a.    1-fan liner (small 1-fan division for growing-on purposes): 10 cm pot size
    b.    2-fan division, blooming size
        (incorrectly known as 1-eye division, #1 division): 10 cm to  #1 pot size
    c.    1-2 fan division, heavy (husky, strong, large blooming size): 10 cm to #2 pot size
2.    Dwarf and miniature daylilies usually make smaller “fans”.
3.    Tetraploid daylilies generally make larger “fans”.
4.    The TC designation should be used when applicable.
5.    The TC* designation should remain even if daylilies are later propagated by division.
6.    TC does not imply an inferior plant, but it may not be uniform or exactly true to the parent plant.

There are many Hemerocallis classifications. These types vary greatly in their ability to thrive well in various climatic zones. Therefore, it is important to consider the particular climatic area when selecting cultivars.

D.    Hosta ssp. - Funkia - “Eye” is the correct term to describe a Hosta division.

1.    Divisions:
    a.    Liner(1-eye) for growing-on purposes:
        10 - 12 cm pot size
    b.    1-eye, heavy grade (well rooted):
        10 - 15 cm pot size, or FC
    c.    1-2 eye, heavy division (also known as extra large or FC): 11.5 cm to #2 pot size
2.    TC designation should be used if applicable.
3.    TC* designation should be maintained even if Hosta is later propagated by division:
    Hosta ‘Royal Standard’ TC - Cell Pack
    Hosta ‘Royal Standard’ TC - 5.5 cm pots
    Hosta ‘Royal Standard’ TC - 1-eye division

E.    Iris - “Fan” is the correct term to describe an Iris division.

1.    Iris ensata (Japanese Iris) and Iris
    Sibirica (Siberian Iris):
    a.    Liner - small 1-fan division for growing on  purposes: 10 - 15 cm pot size
    b.    1-2 fan division (at least 1- fan blooming size), or FC: 11.5 cm to #1 pot size
    c.    2-3 Fan, heavy blooming size division, or FC: #1 to #2 pot size

2.    Bearded Iris - Dwarf, intermediate and tall classifications
    a.    Liner - Non-blooming size rhizome for growing purposes: 10 cm pot size
    b.    Large blooming size rhizomes:
        11.5 cm to #1 pot size

F.    Papaver orientale - Oriental Poppy - Designated whether the plants were propagated from seed or root cuttings.

    1.    5.5 cm pots
    2.    Liners (bare root, field-grown): #1 pot size
    3.    Heavy one-year plants (bare root, field-grown): #1 to #2 pot size

G.    Paeonia - Peony - “Eye” is the correct term to describe a Paeonia division. All eyes counted must be flowering eyes, and/or large non-flowering eyes on heavy roots. Small “eye” buds shall not be counted.
    1.    2-3 eye division: 11.5 cm pot size, or FC
    2.    3-5 eye division (standard): 10 - 15 cm pot size, or FC
    3.    5-7 eye division: #2 to #3 pot size, or FC
    4.    5 eyes and up, or FC: #2 to #3 pot size

H.     Perennials in General - Designate whether bare root, field-grown, propagated vegetatively or from seed.

    1.    Liners or plugs (smallest size):
        10 cm pot size
    2.    Field-grown transplants: 10 cm to #1 pot size
    3.    Heavy field-grown transplants (grown 1 full season before harvesting): 11.5 cm - #2 pot size

I.     A Transplant is a rooted seedling or rooted cutting which has been transplanted at least once.

J.     A Seedling or Liner is a plant grown from seed and grown in a plug, flat, or field bed.

Perennial Plant Container or Pot Sizes
The plant container maximum and minimum dimensions (see chart) are the limits recommended for plant containers classed below. The two dimension are height and inside top diameter.

Unclassified:  Any container of which any one of the two dimensions does not fall within the above specifications.

Standards for Specifying Herbaceous Perennials in Landscape Designs

The purpose of this work is to aid Landscape Architects, Landscape Designers, and Landscape Contractors in their efforts to utilize herbaceous perennials plants in their designs.  As the herbaceous perennial industry is maturing, certain portions are becoming more standardized (i.e. how plants are produced and offered for sale, container sizes, nomenclature).  By informing the design portion of our industry of these standardized elements and the way they affect the handling and end-line use of our products, it is our hope designers will find it easier to specify the materials which more succinctly fit their design needs, and installation contractors will find it easier to procure the specified plants in the specified sizes.

Container Class (Min. - Max.) Height  Inside Top Diameter (Min. - Max.)
6 cm 7 - 9 cm 5.5 - 6.5 cm
7.5 cm 7 - 9 cm 7.5 - 9 cm
10 cm 9 - 9.5 cm 9 - 9.5 cm
11 cm 9 - 13 cm 10 - 12 cm
12 cm 14 - 15 cm 12 - 13 cm
15 cm 14 - 17 cm 15 - 16 cm
#1 15 - 18 cm 15 - 19 cm
#2 19 - 23 cm 19 - 23 cm
#3 22 - 26 cm 22 - 26cm

Because the success of any industry is based on the satisfaction of the end-line consumer, it is imperative that the grower, designer, and contractor work together as a team toward this end. Though an installation should look good the day it has been completed, it is only through time it will mature into the living environment originally conceived by the designer. The ability of the landscape to mature is based on proper installation in properly prepared soil and on continued good maintenance. Toward this end, this work also includes specifications for soil and recommendations of methods which contractors may employ to achieve the desired result.

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