ASTM D5539-94(1998)

NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: D 5539 – 94 (Reapproved 1998)
Standard Specification for
Seed Starter Mix
This standard is issued under the fixed designation D 5539; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope water retention to maintain the amount of moisture needed for
plant use,
1.1 This specification covers the material characteristics,
3.2.3 A surface that does not inhibit emergence. This relates
physical requirements, and sampling appropriate to the desig-
to the media’s ability to resist surface crusting, and
nation of a soil or soil-like material for seed starting purposes.
3.2.4 A bulk density that does not inhibit root elongation
This would consist of the duration of germination ending after
and proliferation.
the cotyledon stage (at the opening of the first true leaves).
3.3 Material—While one material may be able to provide
1.2 Seed starter mix may include natural soils and artificial
all of the needs of a seed (seedling), a mixture of varying
mixtures of natural or artificial materials used for the initial
percentage of at least two of these materials has been found in
germination of seeds to the cotyledon stage.
practice to yield more consistent results over a wide range of
2. Referenced Documents
management practices. Therefore, seed starters are generally
mixtures of materials. The following is a list of materials that
2.1 ASTM Standards:
have been used as or in seed starter mixes:
C 330 Specification for Lightweight Aggregates for Struc-
3.3.1 Vermiculite—This is a natural mineral that has been
tural Concrete
treated with heat until it becomes porous. This material has the
C 331 Specification for Lightweight Aggregates for Con-
ability to hold a significant amount of water and still allow for
crete Masonry Units
excellent drainage. However, it does not provide for good
D 653 Terminology Relating to Soil, Rock, and Contained
seed-media contact.
Fluids
3.3.2 Sphagnum Peat Moss—This is a natural accumulation
D 2607 Classification of Peats, Mosses, Humus, and Re-
of plant material decayed and decaying under anaerobic
lated Products
conditions, and meeting the specifications outlined in Classi-
D 4531 Test Methods for Bulk Density of Peat and Peat
fication D 2607. Industry-wide, this seems to be the one
Products
material that has no substitute.
E 11 Specification for Wire-Cloth Sieves for Testing Pur-
3.3.3 Perlite—This is a volcanic ash that looks like small
poses
beads of plastic. Similar to vermiculite, it holds less water but
3. Material and Manufacture
provides more seed-media contact.
3.3.4 Coarse Sand—This is mineral soil material that passes
3.1 The success of a seed starter mix is measured in its
through a No. 10 sieve but is retained on a No. 40 sieve. It
ability to provide a germinating seed with certain basic needs,
provides good drainage and maintains friability.
that are outlined as follows. A variety of materials, both natural
3.3.5 Expanded Shale, Clay, or Slate— These are engi-
and artificial, can be employed to provide the characteristics
neered materials that are structural grade, inert, porous light-
that will fill the need.
weight aggregates with properties meeting the requirements of
3.2 Function—A seed starter media provides a seed (seed-
Specification C 330 and C 331. Because of their particle
ling) with four basic needs:
strength these aggregates do not consolidate after initial
3.2.1 Aeration to permit an exchange of gases between the
compaction and are thus free draining.
emerging roots and the surrounding medium,
3.3.6 Peat Humus and Other Peat Products— This material
3.2.2 Adequate seed (seedling) to starter media contact to
is more highly decomposed than the sphagnum variety. It
permit water to flow to the seed and seedling root. This
meets the specifications outlined in Classification D 2607.
function also relates to the media having a sufficient amount of
While it may be used in the mixture, it tends to compact easily.
3.3.7 Composted Organic Materials—This material has de-
This specification is under the jurisdiction of ASTM Committee D-18 on Soil
sirable nutrient qualities if the seedling is not to be trans-
and Rock and is the direct responsibility of Subcommittee D18.22 on Soil as a
Medium for Plant Growth. planted; however, it has the same drawbacks as the peat humus.
Current edition approved April 15, 1994. Published June 1994.
Other properties of this material may or may not be desirable
Annual Book of ASTM Standards, Vol 04.02.
depending on the organic parent material and the manner of
Annual Book of ASTM Standards, Vol 04.08.
composting.
Discontinued; see 1992 Annual Book of ASTM Standards, Vol. 04.08.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
----
...