1、Designation: D 5539 94 (Reapproved 2003)Standard Specification forSeed Starter Mix1This standard is issued under the fixed designation D 5539; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in p
2、arentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers the material characteristics,physical requirements, and sampling appropriate to the desig-nation of a soil or soil-like
3、 material for seed starting purposes.This would consist of the duration of germination ending afterthe cotyledon stage (at the opening of the first true leaves).1.2 Seed starter mix may include natural soils and artificialmixtures of natural or artificial materials used for the initialgermination of
4、 seeds to the cotyledon stage.2. Referenced Documents2.1 ASTM Standards:C 330 Specification for Lightweight Aggregates for Struc-tural Concrete2C 331 Specification for Lightweight Aggregates for Con-crete Masonry Units2D 653 Terminology Relating to Soil, Rock, and ContainedFluids3D 2607 Classificati
5、on of Peats, Mosses, Humus, and Re-lated Products4D 4531 Test Methods for Bulk Density of Peat and PeatProducts3E 11 Specification for Wire-Cloth Sieves for Testing Pur-poses23. Material and Manufacture3.1 The success of a seed starter mix is measured in itsability to provide a germinating seed with
6、 certain basic needs,that are outlined as follows. A variety of materials, both naturaland artificial, can be employed to provide the characteristicsthat will fill the need.3.2 FunctionA seed starter media provides a seed (seed-ling) with four basic needs:3.2.1 Aeration to permit an exchange of gase
7、s between theemerging roots and the surrounding medium,3.2.2 Adequate seed (seedling) to starter media contact topermit water to flow to the seed and seedling root. Thisfunction also relates to the media having a sufficient amount ofwater retention to maintain the amount of moisture needed forplant
8、use,3.2.3 A surface that does not inhibit emergence. This relatesto the medias ability to resist surface crusting, and3.2.4 A bulk density that does not inhibit root elongationand proliferation.3.3 MaterialWhile one material may be able to provideall of the needs of a seed (seedling), a mixture of v
9、aryingpercentage of at least two of these materials has been found inpractice to yield more consistent results over a wide range ofmanagement practices. Therefore, seed starters are generallymixtures of materials. The following is a list of materials thathave been used as or in seed starter mixes:3.
10、3.1 VermiculiteThis is a natural mineral that has beentreated with heat until it becomes porous. This material has theability to hold a significant amount of water and still allow forexcellent drainage. However, it does not provide for goodseed-media contact.3.3.2 Sphagnum Peat MossThis is a natural
11、 accumulationof plant material decayed and decaying under anaerobicconditions, and meeting the specifications outlined in Classi-fication D 2607. Industry-wide, this seems to be the onematerial that has no substitute.3.3.3 PerliteThis is a volcanic ash that looks like smallbeads of plastic. Similar
12、to vermiculite, it holds less water butprovides more seed-media contact.3.3.4 Coarse SandThis is mineral soil material that passesthrough a No. 10 sieve but is retained on a No. 40 sieve. Itprovides good drainage and maintains friability.3.3.5 Expanded Shale, Clay, or Slate These are engi-neered mat
13、erials that are structural grade, inert, porous light-weight aggregates with properties meeting the requirements ofSpecification C 330 and C 331. Because of their particlestrength these aggregates do not consolidate after initialcompaction and are thus free draining.3.3.6 Peat Humus and Other Peat P
14、roducts This materialis more highly decomposed than the sphagnum variety. Itmeets the specifications outlined in Classification D 2607.While it may be used in the mixture, it tends to compact easily.1This specification is under the jurisdiction of ASTM Committee D18 on Soiland Rock and is the direct
15、 responsibility of Subcommittee D18.22 on Soil as aMedium for Plant Growth.Current edition approved April 15, 1994. Published June 1994.2Annual Book of ASTM Standards, Vol 04.02.3Annual Book of ASTM Standards, Vol 04.08.4Discontinued; see 1992 Annual Book of ASTM Standards, Vol. 04.08.1Copyright AST
16、M International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.3.7 Composted Organic MaterialsThis material has de-sirable nutrient qualities if the seedling is not to be trans-planted; however, it has the same drawbacks as the peat humus.Other properties of t
17、his material may or may not be desirabledepending on the organic parent material and the manner ofcomposting.3.3.8 Other Organic MaterialsWhile raw organic mattermay be tempting from the standpoint of increased friability, itmay lead to nitrogen depletion and pest (disease and insect)problems. Also,
18、 some wood products contain natural andartificial toxins which are lethal to plants. As such, eachmaterial would have to be evaluated on its own merit.3.3.9 Other Inorganic MaterialsThis category includescinders, ashes, and a variety of artificial inert soil-like material.Each of these materials wou
19、ld have to be evaluated based on itsability to hold moisture, soluble salt content, resistance tocompaction, and pH.3.4 DensityThe bulk density of the media must be suchthat it does not inhibit plant emergence or root elongation. Abulk density less than 1.3 g/cm3(on an oven dry basis) has beenfound
20、in practice to provide adequate results. This measure-ment is made using Test Method D 4531 for the dry density ofthe media.3.5 pHThe optimum pH for a seed starter media varies bythe species of the plant being grown. Thus, a specific optimumrange of pH is not appropriate for this specification. Howe
21、ver,the pH must not be extremely acidic or basic.3.6 Soluble SaltsThe concentration of soluble salts mustbe such that it will result in a conductivity less than 3.5 mmhos(0.35 S/m).5Also the portion of the concentration of saltsattributable to sodium (Na) or chloride (Cl) must not exceed10 % of the
22、total salt concentration. Conductivity measure-ments are made by method 10-3.3 in Agronomy No. 9, Part 2.63.7 NutrientsSince seeds contain their own food supply,the nutrient content of the growth media is not an issue. Overthe germination period covered by this specification, seeds willsprout and fo
23、rm healthy seedlings in a mixture totally devoid ofnutrients. However, low concentrations of nutrients in themixture pose no drawbacks in the stage of seedling growthcovered by this specification and may yield certain advantages.Nutrients in a starter mix also allows a seedling to remain in thesame
24、media further into its life, reducing the need for trans-planting. Since nutrients pose no harm and are beneficial to theplant in later seedling growth stages, the issue of plant nutrientsin the seed starter mix is left to the individual manufacturer oruser.3.8 SanitationGerminating seedlings are ex
25、tremely vul-nerable to insects and diseases. To protect the seedling throughthis period, handling of the media must be as sanitary aspractical to reduce the amount of harmful insect eggs andlarvae, nematodes, viruses, and microbes. Further sterilizationtechniques can be used, if desired.4. Rejection
26、4.1 The mixture cannot be labeled as a seed starter mix if itfails to conform to any of the requirements of this specification.5. Packaging and Package Marking5.1 Unless otherwise specified in the purchase contract orby the purchaser, the prepared mix is packaged in variousquantities. Bales and bulk
27、 sales are also allowed.5.2 Unless otherwise specified in the purchase contract orby the purchaser, the name of the manufacturer, name ofproduct, net volume, and a statement denoting compliance withthis specification shall be legibly marked on each package.6. Keywords6.1 horticulture; peat; seed sta
28、rter; seedings; soilASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement
29、 of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or fo
30、r additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known
31、 to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM
32、at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).5A conductivity of 3.6 mmhos (0.35 S/m) is safe for most plants; however, somesalt sensitive plant species can be damaged by a conductivity of 3.5 mmhos.6“Methods of Soil Analysis,” Method 10-3.3, Agronomy No. 9, Part 2, AmericanSociety of Agronomy, Madison, WI 1982.D 5539 94 (2003)2
