This specification covers the material characteristics, physical requirements, and sampling, of soil or soil-like material for seed starter mix. Starter mix may include natural soils and mixtures of natural or artificial materials for use in initial germination of seeds to the cotyledon stage. Seed starter mix shall be able to provide a germinating seed with basic needs such as aeration, water retention, surface crusting resistance, nutrients, soluble salts, optimum pH, sanitation, and bulk density that does not inhibit root elongation. Materials for seed starter mix may include vermiculite, sphagnum peat moss, perlite, coarse sand, expanded shale, clay, slate, peat humus, other peat products, composted organic materials, and other organic and inorganic materials.

1.1 This specification covers the material characteristics, physical requirements, and sampling appropriate to the designation of a soil or soil-like material for seed starting purposes. This would consist of the duration of germination ending after the cotyledon stage (at the opening of the first true leaves).

1.2 Seed starter mix may include natural soils and artificial mixtures of natural or artificial materials used for the initial germination of seeds to the cotyledon stage.

1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. Alternate sieve designations in parentheses are as provided in Specification E11.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

1.5 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.