FORMAL RECOMMENDATION BY THE

NATIONAL ORGANIC STANDARDS BOARD (NOSB) 

TO THE NATIONAL ORGANIC PROGRAM (NOP) 

Date: April 29, 2010 

Subject: Production Standards for Terrestrial Plants in Containers and Enclosures 

(Greenhouses) 

Chair: Daniel G. Giacomini 

 

Recommendation

The NOSB hereby recommends to the NOP the following: 

Rulemaking Action: X 

Guidance Statement: 

Other: 

Summary Statement of the Recommendation (including Recount of Vote): 

The NOSB voted 12 yes, 1 no, and 2 absent in favor of a Production Standard for Terrestrial 

Plants in Containers and Enclosures (Greenhouses). This recommendation sets forth guidelines by 

which normally terrestrial plants, not including mushrooms, sprouts, and micro-greens; may be 

certified organic under a new section of the Crops Standard 205.209. 

NOSB Vote: Motion: Tina Ellor Second: Jeffrey Moyer

Board vote: Yes - 12 No- 1 Abstain- 0 Absent - 2 

Summary Rationale Supporting Recommendation (including consistency with OFPA and 

NOP): 

Please see Appendix A attached to this document for a brief history of this issue, starting in 1995. 

In Fall of 2001, the NOSB passed a Greenhouse Production System recommendation, also 

attached. In 2003, the Crops Committee prepared a guidance document relative to hydroponics 

and other soil-less growing systems (Appendix A). Another Guidance Statement relative to Soilless growing systems was prepared by the Crops Committee in April, 2008; also attached. Two 

more versions of a ‘soil-less recommendation’ were brought forth by the Crops Committee: one 

in May of 2009, and another in November of 2009. Each time a new versions was brought 

forward, changes were made in response to public comment and input on the previous version. 

The final version, brought forward to the full board by the Crops Committee for the April, 2010 

NOSB is a result of these years of work, discussion, and input from our stakeholders. 

Response by the NOP:
National Organic Standards Board (NOSB) 

Crops Committee Recommendation 

Production Standards for Terrestrial Plants in Containers and Enclosures 

(Greenhouses) 

January 23, 2010 

I. Introduction: 

This recommendation for rulemaking addresses certain aspects of greenhouse 

production that are commonplace in indoor cropping methods, such as container based 

rooting media (potting mixtures), hydroponics, and aeroponics. Additionally, provisions 

are put forth to protect against contamination and commingling of organic crops by nonorganic crops in the same greenhouse structure or adjacent ones. 

II. Background 

In May 2009 the Crops Committee presented for discussion a document clarifying the 

NOSB’s position on soil-less growing systems, such as hydroponics, as they pertain to 

organic certification to the USDA National Organic Program standards. The present 

recommendation focuses on greenhouse production, but it is based on the same criteria 

and principles outlined in the soil-less systems document. 

III. Discussion 

The organic farming method derives its name from the practice of maintaining or 

improving the organic matter (carbon containing) content of farm soil through various 

methods and practices. The reason this is the central theme and foundation of organic 

farming is not inherent to the organic matter itself, but is based on the importance of the 

organic matter to the living organisms that inhabit soils, particularly for its positive 

influence on proliferation of diverse populations of organisms that interact in a beneficial 

way with plant roots. These microscopic organisms, found in abundance in well 

maintained soils, interact in a symbiotic manner with plant roots, producing the effect of 

strengthening the plant to be able to better resist or avoid insect, disease and nematode 

attack, as well as assisting the plant in water and mineral uptake. The abundance of 

such organisms in healthy, organically maintained soils form a biological network, an 

amazing and diverse ecology that is ‘the secret’, the foundation of the success of organic 

farming accomplished without the need for synthetic insecticides, nematicides, 

fumigants, etc. In practice, the organic farmer is not just a tiller of the soil, but a steward 

of the soil ecology on the farm, hence some of the alternate names for this realm of 

production, such as ecological or biodynamic farming. 

Observing the framework of organic farming based on its foundation of sound 

management of soil biology and ecology, it becomes clear that systems of crop 

production that eliminate soil from the system, such as hydroponics or aeroponics, can 

not be considered as examples of acceptable organic farming practices. Hydroponics, 

the production of plants in nutrient rich solutions or moist inert material, or aeroponics, a 

variation in which plant roots are suspended in air and continually misted with nutrient 

solution, have their place in production agriculture, but certainly cannot be classified as 
certified organic growing methods due to their exclusion of the soil-plant ecology intrinsic 

to organic farming systems and USDA/NOP regulations governing them. 

IV. Relevant Areas in the Rule 

The OFPA specifically required an organic plan designed to foster soil fertility (§6513b) 

and the NOP regulations resulting from the Act bear this out as follows: 

§205.203(a)- The producer must select and implement tillage and cultivation practices 

that maintain or improve the physical, chemical, and biological condition of the soil. 

§205.203(b)- The producer must manage crop nutrients and soil fertility through 

rotations, cover crops, and the application of plant and animal materials. 

§205.203(c)- The producer must manage plant and animal materials to maintain or 

improve soil organic matter content in a manner that does not contribute to 

contamination... 

Although the regulations do not specifically state ‘soil only production’, the exclusion of 

soil from organic production of normally terrestrial, vascular plants violates the intent of 

the regulations. This intent can be seen in these sections of the rule that require proper 

stewardship toward improving and maintaining the soil ecology within an organic farming 

system. It is pointed out that naturally aquatic plant species and non-vascular plant 

species such as mushrooms come from different (non-soil) ecological niches and would 

be handled separately. Sprouts (the sprouted radicle and hypocotyl of seeds) are 

produced without soil by design and are not subject to this recommendation. 

In previous Crops Committee discussion documents, the question has been asked: 

“Should container culture based growing media (typically utilized in greenhouse 

systems) that are predominately compost and compostable plant materials be 

considered ‘soil’. As highlighted in earlier portions of this document, a foundational 

principle of organic farming is the practice of maintaining and nurturing soil health so as 

to foster the proliferation of the proper soil biology with their accompanying ecologies. 

Since all typical soil dwelling organisms, such as earthworms, protozoa, fungi, bacteria, 

actinomycetes, etc. can thrive in a properly designed compost based growing media, 

producing the beneficial symbiotic ecological relationships found in soil, such growing 

media should be rightfully considered soil. 

V. Recommendation 

§ 205.2 Terms Defined 

Greenhouse- Permanent enclosed structure that allows for an actively controlled 

environment used to grow organic crops, annual seedlings or planting stock used in 

organic production. 

Hydroponics- The production of normally terrestrial, vascular plants in nutrient rich 

solutions or in an inert, porous, solid matrix bathed in nutrient rich solutions. 

Aeroponics- A variation of hydroponics in which plant roots are suspended in air and 

misted with nutrient solution. 
Containers- Any vessel and associated equipment used to house growing media and the 

complete root structure of terrestrial plants and to prevent the roots from contacting the 

soil or surface beneath the vessel, such as, but not limited to, pots, troughs, plastic bags, 

floor mats. etc. 

Growing media- Material which contains sufficient organic matter capable of supporting 

the plant root system and a natural and diverse soil ecology. 

§ 205.209 Terrestrial Plants in Containers and Enclosures (Greenhouses) 

(a) Container and enclosure (Greenhouse) operations must meet all applicable 

requirements of subparts B (205.105) and C (205.200 – 205.206) except that: 

(1) The producer operating a greenhouse with crops grown in containers using a 

growing media that does not include soil from the production site is exempt from 

requirements of 205.202(b), 205.203(a). 

(2) In addition, the growing container based producer is exempt from the crop 

rotation and cover cropping requirements in section 205.203(b) and 205.205. In 

lieu of crop rotation and cover cropping, soil regeneration and recycling practices 

shall be implemented and documented for the certification agent in order to 

demonstrate that the required functions/goals of crop rotation and cover cropping 

listed in 205.205(a, b, c, d) have been achieved through these alternate 

practices, as applicable to the operation. Specifically: 

(i) Maintain or improve soil organic matter content (a)- Examples include, 

but are not limited to, recycling and re-use of growing media, addition 

of compost and other compostable materials, earthworm 

replenishment, microbial re-inoculation, etc. 

(ii) Provide for pest management in crops (b)- Such as soil borne 

damping-off control through various low temperature heating 

methods. Soil inoculation using disease suppressant bacteria and 

fungi. 

(iii) Manage deficient or excess plant nutrients (c)- Recycle excess plant 

nutrients contained in drain water from media containers, avoiding so 

called drain-to-waste systems. Recycled nutrients must be re-used in 

the greenhouse, or alternatively, on a growing crop outside the facility. 

(iv) Provide erosion control (d)- Though erosion is not generally 

applicable to greenhouse production, recycling of drain water 

prevents off-site movement of nutrients, a common consequence of 

typical field erosion. 

(b) Growing media ingredients shall be verified by certifying agent and shall not include as 

ingredients any prohibited materials. Growing media shall be comprised of ingredients that 

allow for recycling and re-use as growing media within the operation, or alternatively, as a 

crop input outside the greenhouse. Growing media shall not be disposed of as waste, but 

should be recycled or reused whenever possible. Growing media shall contain sufficient 

organic matter capable of supporting natural and diverse soil ecology. For this reason, 

hydroponic and aeroponic systems are prohibited. Growing media used to produce crop 

transplants should also be capable of supporting a natural and diverse soil ecology. 
(c) Producers may use full-spectrum light sources. 

(d) Plants and soil shall not be in direct contact with, or indirect contact with condensates 

from, wood treated with prohibited materials that are used for greenhouse structures 

or frames of raised beds. 

 

(e) To comply with the provisions of 205.201(a)(5) to prevent commingling and 

contamination, organic and non-organic crops can be grown within the same 

structure only if the following conditions are met: 

(1) An impermeable wall shall separate organic and non-organic production sites if 

prohibited materials are applied to the non-organic crop to ensure that cross 

contamination does not occur. 

(2) The ventilation systems must ensure that prohibited materials cannot drift, or be 

otherwise conveyed to the organic production area. 

(3) Separate watering systems must be established if prohibited fertilizers and/or 

pesticides are injected within the watering system. 

(4) Producers must ensure that no contamination occurs to the organic crop through 

cross-pollination with crops produced through genetic engineering 

(5) Soil mixing machines and other equipment used for non-organic crop production 

must be thoroughly cleaned prior to use in organic production. 

(6) Adequate physical facilities, as determined by the certifying agent, shall separate 

organic and non-organic crops and production materials in storage, production or 

holding areas. 

(7) Organic and non-organic crops and production areas must be conspicuously 

labeled. 

Voting: Motion: Tina Ellor Second: Rigoberto Delgado 

Yes: 5 No: 0 Absent: 1 Abstain: 0

NA 
NOSB Final Recommendation 

Greenhouse Production Systems 

October 2001 

Add definition: 

Greenhouse- Enclosed structure used to grow organic crops, annual seedlings or 

planting stock used in organic production. 

§205.209 Greenhouse Production Systems 

(a) Greenhouse operations must meet all applicable requirements of 

subparts B (205.105) and C (205.200 – 205.206) except that: 

(1) The producer operating a greenhouse with crops grown in 

containers is exempt from requirements of 205.202, 205.203(a) and 

205.205. In addition, the producer is exempt from the crop rotation 

and cover cropping requirements in section 205.203(b). The 

production environment must prevent contact between organically 

produced crops and prohibited substances as listed in 205.105 

throughout the entire production period. 

(2) The producer of an in-ground permanent soil greenhouse system 

can seek an exemption from the crop rotation requirements of 

sections 205.203, and 205.205-205.206 provided that effective 

alternative strategies for developing and maintaining plant and soil 

health are established and approved by the certifying agent. 

(b) The use of potting mixtures containing prohibited materials is not 

allowed. 

(c) Producers may use artificial light sources 

(d) Plants and soil shall not be in direct contact with wood treated with 

prohibited materials that is used for greenhouse structures or frames of 

raised beds. 

 

(g) If a producer is growing both organic and non-organic greenhouse 

crops, the producer must comply with the provisions of 205.201(a)(5) 

to prevent commingling and contamination. 

(h) Organic and non-organic crops can be grown within the same structure 

if the following conditions are met: 
1. An impermeable wall shall separate organic and non-organic 

production sites if prohibited pesticides are applied to the 

non-organic crop at a time when the organic crop is present. 

2. Adequate provisions must be made to prevent 

contamination of organic crops when producers alternate 

between organic and non-organic production during different 

times of the year. 

3. The ventilation system must ensure that prohibited materials 

do not drift to the organic production area. 

4. Separate watering systems must be established if prohibited 

fertilizers and/or pesticides are injected within the watering 

system. 

5. Producers must insure that no contamination occurs to the 

organic crop through cross-pollination with crops produced 

through genetic engineering.

6. Soil mixing machines and other equipment used for nonorganic crop production must be thoroughly cleaned prior to 

use in organic production, except that pesticide sprayers 

used in conventional production can not be used for organic 

production purposes. 

7. Adequate physical facilities, as determined by the certifying 

agent, shall separate organic and non-organic crops and 

production materials in storage, production or holding areas. 

8. Organic and non-organic crops and production areas must 

be conspicuously labeled. 
Crops Committee Discussions on Guidance Statements Relative to 

Soil-less Growing Systems 

April, 2008 

 

The Crops Committee of the NOSB is gathering information and discussing the 

formation of a recommendation to the NOP for rulemaking on the subject of soil-less 

growing systems in organic production. Previous discussion or recommendation 

documents have been put forth by the Crops Committee wherein the term 

‘hydroponics’ has been used. The current committee chooses to drop this term from 

the title of this and future documents, selecting the more all inclusive ‘soil-less 

growing systems’ title. 

In 2003, the NOSB Crops Committee issued a proposed guidance document that 

included the following questions pertaining to the validity of organic certification of 

soil-less growing systems (with edits and additions by the current committee): 

1. The over-riding question of whether soil-less systems are compatible 

with organic production. 

2. Should container culture methods utilizing compost be more 

appropriately considered as soil-bearing cultures. 

3. Appropriate guidelines on sources and types of fertilizers to be 

allowed, such as natural materials made into fertilizers using synthetic 

extractants or stabilizers, allowed synthetic micronutrients, manure or 

other animal product based fertilizers (as they relate to food safety 

issues) 

4. How to address leaching problems with open systems. 

5. Appropriate source of media for container culture systems 

6. Composition of inert ingredients in soil-less media systems 

7. Disposal vs. recycling of wastes 

From the same 2003 Guidance, the following recommendation was proposed: 

Hydroponic and other soil-less systems for crop production are limited to the 

following, categories: 

1. Production of higher plants that are naturally aquatic species. 

2. Production of algal organisms such as spirulina. 

3. Production systems that utilize compost as a growing media. 

In aquaponic systems that include fish and plant species, the plant component 

must also meet the above requirements. Certifiers must validate producer plans 

that insure that fish effluent is used in a manner that does not lead to a buildup of 

human pathogens on the crops that are produced. 

These recommendations were never voted on by the full NOSB and are 

presented here as background for the current Crops Committee work in 

progress. The questions raised by the 2003 work could also serve as a guide for 
public comment from interested parties. The entire 2003 Crops Committee 

document is attached at the end as Appendix A. 

In addition to the topics put forward from the 2003 Guidance, the Crops 

Committee must consider the following questions: 

1. What systems (terrestrial, aquaculture, aquaponic, etc.) should be 

considered when providing soil-less recommendations? 

2. Are soil-less systems currently certified in the US and if so in what areas 

and for what plants? 

 3. The question of sustainability of soil-less systems that are completely and 

 perpetually dependent on off-farm inputs. 

Lastly, the Committee encourages comment by certifiers regarding these 

previously presented questions: 

1. Do you currently certify any hydroponics (soil-less) operations as organic? 

If not, why? 

2. Do you think that organic certification of hydroponics (soil-less) is 

appropriate? Why or why not? 

3. For hydroponics (soil-less) operations you currently certify, which 

practices, if any, are difficult to determine if they comply with the intent of 

standards used for soil? 

4. Do you maintain a list of allowed/prohibited substances for use in 

hydroponics? 

The current Crops Committee continues to elicit comment from the public in 

order to determine the proper status of the various soil-less growing systems with 

reference to organic certification. It is our intent to intensively study the many and 

varied forms of these growing methods and produce a formal recommendation 

by the Spring 2009 NOSB meeting. 
Appendix A 

 

Crops Committee Recommendations for a Guidance Document Relative to 

Hydroponics and Otber Soil-less Growing Systems: 

Prepared by Owusu Bandele- 2003 

Background 

In 1995, the NOSB stated that hydroponic production systems could possibly be 

conducted as organic operations as long as these systems met the other requirements 

of the national standards. The NOP's current position is that hydroponic systems are 

already covered by the existing rule (as has been stated by current program leader 

Mr.Richard Mathews). At the October, 2002 NOSB meeting, the board recommended 

that producers of spirulina be allowed to use Chilean nitrate as the sole source of 

nitrogen in their systems until October, 2005. However, neither the TAP review, or the 

NOSB's decision addressed the issue of whether or not this type of production system 

qualifies for organic certification. 

Since hydroponic systems are already covered by the Final Rule, questions can arise as 

to what, if any systems actually qualify for organic certification by certifiers, and what 

yardsticks will certifiers use to make these determinations? Moreover, since so much of 

organic philosophy and production is built around establishing and maintaining healthy 

soils, how can soil-less systems be effectively evaluated using the organic standards 

found in the final rule? More importantly, can hydroponic systems qualify for organic 

certification? 

Types of Soil·less Systems

Hydroponic systems utilize fertilizers which are dissolved in solution. There are two basic 

types: liquid hydroponics and aggregrate hydroponics. Liquid systems include the 

nutrient film technique (NFT), aeroponics, floating raft and noncirculating water culture. 

The NFT system, which is commonly used in commercial hydroponics, involves a 

closed, recirculating system. Nutrient from organic sources are available for these 

systems such as solutions prepared from blood meal, rock phosphate, guano, etc. 

Aggregate systems involve media mixes in bags, troughs, trenches, or in benches 

systems. Some aggregate systems are also called drip or substrate systems. Common 

media include perlite or rock wool. 

Questions to consider with "organic" hydroponic systems: 

1. The over-riding question of whether soil-less systems are compatible with 

organic production (which is relevant to all of the systems discussed in this 

document). 

2. Source of fertilizers: 

3. Leaching problems with open systems 

4. Source of media for aggregate systems 

5. Composition of inert ingredients 

6. Disposal of wastes 
Aquacultural systems involve the production of aquatic plants and animals in somewhat 

controlled environments. The Aquatic Task Force provided recommendations for the 

production of most aquatic species of fish. However, the NOSB review of the petition 

involving the use of Chilean nitrate for spirulina production was assigned to the Crops 

Committee. Therefore, it is appropriate for the Crops Committee to consider the question 

of suitability of spirulina production for organic certification. 

Questions to Consider (In addition to those cited above) 

1. Over the long run, can the systems become more sustainable with less 

reliance on outside inputs? 

Aquaponic systems combine the features of both hydroponics and aquaculture. This is 

done by recirculating the effluent from fish tanks and using it as a source of nutrients for 

vegetables grown hydroponically. Using sand or gravel as media. Nitrifying bacteria 

convert the fish effluent, primarily ammonia, to nitrite and then nitrate, which the plants 

can use. Diver (Aquaponics-Integration of Hydroponics With Aquaculture, 2000) 

points out several sustainable aspects of aquaponic systems including the following: 

• Waste materials from one biological systems are used as a source of food or 

fuel for a second system; 

• The integration of the production offish and plants increase diversity, and in 

turn, system sustainability; 

• Biological filtration cleanses the water before it leaves the system; and 

• It is possible that the only fertility input would be the fish feed. 

Questions to consider: 

1. Relevance of the source of fish feed (Can the vegetables be considered 

organic if the fish are not raised organically?). 

2. Safety concerns and waiting period between fertigation with fish effluent and 

harvest of the crops. 

Other Soil-less Systems: 

Bag cultures involve the growing of crops in a soil-less media. They can be used within 

aggregrate hydroponic systems where liquid fertilizers are applied through the drip 

system. Media for the bags can include vermiculite, peat moss, rice hulls, and other 

mixes. In non- hydroponic bag cultures, compost is often added to the bag. Vertical 

towers are another form of bag culture in which long bags full of soil-less media are hung 

from beams or wires, and plants are grown through holes or slits in the sides of the bag. 

Questions: 

1. Should all soil-less bag culture systems be considered along with 

hydroponics, or only those involved in hydroponic production? 

2. What materials are found in the polyethylene bags that are used? 

3. How is leaching prevented from the drainage holes in the bags to the 

greenhouse soil? 
Straw bale cultures were used in the greenhouse much more frequently in the past, 

before the advent of the nutrient film technique and rock wool. Under this system, the 

greenhouse floor (which could be concrete, or lined with plastic) is covered with straw 

bales. The bales are normally wetted with compost tea mixtures to expedite heating and 

decomposition. The bales are then covered with a layer of compost. Organic fertilizers 

are then applied as topdressings to the bale, and plants can also be foliar-fed. 

Shallow bed cultures are another form of soil-less culture in which a thin layer of 

compost is placed over a plastic woven weed barrier for the production of shallow-rooted 

herbs and vegetables. 

Questions: 

1. Should the shallow bed and straw bale cultures be more appropriately 

considered as soil-bearing cultures, since they both involve the addition of 

composts? This would also hold true for the bag cultures containing compost. 

2. How is leaching of nutrients prevented to the areas surrounding the 

greenhouse? 

Other General Considerations: (Assuming that at least some soil-less systems will be 

eligible for certification) 

1. Several sources have noted an increase in economic feasibility for 

hydroponic and aquaponic production. How many hydroponic/aquaponic 

producers are seeking or will be seeking organic certification? 

2. Are current certifiers, many of whom have specialized in certification of 

soilbased systems, qualified to handle this type of certification? If not, how 

will they be bought up to speed? 

Current Status: 

Not many hydroponic systems exist world-wide that have obtained organic certification. 

There are a few operations that produce spirulina in Europe that have obtained organic 

certification. The United Kingdom does not permit organic certification for hydroponic 

operations. British Columbia and New Zealand also do not allow for certification of 

hydroponic production systems. 

In the United States, opinions among certifying agents is divided. For example, 

California Certified of Organic Farmers can certify hydroponic operations if inputs 

approved for organic production are used while Oregon Tilth will not certify hydroponic 

systems. 
 

NOSB Crops Committee 

Soil-less Growing Systems Discussion Item 

May 2009 Meeting 

This document seeks to clarify the NOSB Crops Committee position on soil-less 

growing systems, such as hydroponics, as they pertain to organic certification to 

the USDA National Organic Program standards. This clarification represents a 

portion of the work in progress toward the overall goal of forming an updated 

NOSB Greenhouse Production Standard recommendation for presentation to the 

NOP for rulemaking at the Fall 2009 meeting. 

Introduction 

The organic farming method derives it’s name from the practice of maintaining or 

improving the organic matter (carbon containing) content of farm soil through 

various methods and practices. The reason this is the central theme and 

foundation of organic farming is not inherent to the organic matter itself, but is 

based on the importance of the organic matter to the living organisms that inhabit 

soils, particularly for it’s positive influence on proliferation of diverse populations 

of organisms that interact in a beneficial way with plant roots. These microscopic 

organisms, found in abundance in well maintained soils, interact in a symbiotic 

manner with plant roots, producing the effect of strengthening the plant to be able 

to better resist or avoid insect, disease and nematode attack, as well as assisting 

the plant in water and mineral uptake. The abundance of such organisms in 

healthy, organically maintained soils form a biological network; an 

amazing and diverse ecology that is ‘the secret’, the foundation of the success of 

organic farming accomplished with a minimal need for synthetic fertilizers, 

insecticides, nematicides, fumigants, etc. In practice, the organic farmer is not 

just a tiller of the soil, but a steward of the soil ecology on the farm, hence some 

of the alternate names for this realm of production, such as ecological or 

biodynamic farming. 

Discussion 

Observing the framework of organic farming based upon it’s foundation of sound 

management of soil biology and ecology, it becomes clear that systems of crop 

production that eliminate soil from the system, such as hydroponics or 

aeroponics, can not be considered as examples of acceptable organic farming 

practices. Hydroponics, the production of plants in nutrient rich solutions or moist 

inert material, or aeroponics, a variation in which plant roots are suspended in air 

and continually misted with nutrient solution, have their place in production 

agriculture, but certainly cannot be classified as certified organic growing 
methods due to their exclusion of the soil-plant ecology intrinsic to organic 

farming systems and USDA/NOP regulations governing them. 

The OFPA specifically requires an organic plan designed to foster soil fertility 

(§6513b) and the NOP regulations resulting from the Act bear this out as follows: 

§205.203(a)- The producer must select and implement tillage and cultivation 

practices that maintain or improve the physical, chemical, and biological 

condition of the soil. 

§205.203(b)- The producer must manage crop nutrients and soil fertility through 

rotations, cover crops, and the application of plant and animal materials. 

§205.203(c)- The producer must manage plant and animal materials to maintain 

or improve soil organic matter content in a manner that does not contribute to 

contamination... 

Clearly, the ramifications of the regulations preclude the exclusion of soil from 

organic production systems, except for the production of naturally aquatic plant 

species and mushrooms. 

In previous Crops Committee discussion documents, the question has been 

asked: “Should container culture based growing media (typically utilized in 

greenhouse systems) that are predominately compost and compostable plant 

materials be considered ‘soil’. As highlighted in earlier portions of this document, 

a foundational principle of organic farming is the practice of maintaining and 

nurturing soil health so as to foster the proliferation of the proper soil biology with 

their accompanying ecologies. Since all typical soil dwelling organisms, such as 

earthworms, insects, arachnids, protozoa, fungi, bacteria, and actinomycetes can 

thrive in a properly designed compost based growing media, producing the 

beneficial symbiotic ecological relationships found in soil, such growing media 

should be rightfully considered soil. The Committee will be preparing guidelines 

concerning the proper make-up, handling, and recycling of such growing media 

as part of the forthcoming updated Greenhouse Production Standards 

Recommendation mentioned earlier. 

 
 

NOSB- Crops Committee Recommendation 

Greenhouse Production Systems 

September, 2009 

NOSB recommendation for rulemaking pertaining to Greenhouse Production 

Systems 

Introduction: 

This recommendation for rulemaking addresses certain aspects of greenhouse 

production that are commonplace in indoor cropping methods, such as container 

based rooting media (potting mixtures), hydroponics, and aeroponics. 

Additionally, provisions are put forth to protect against contamination and 

commingling of organic crops by non-organic crops in the same greenhouse 

structure or adjacent ones. For additional discussion and guidance on the topic of 

hydroponics, aeroponics, and other soil less cropping systems, see the 

document “NOSB Crops Committee- Soil less Growing Systems, May 2009” 

attached here as Addendum A. 

Recommendation: 

Add definition: 

Greenhouse- Enclosed structure used to grow organic crops, annual seedlings or 

planting stock used in organic production. 

205.209 Greenhouse Production Systems 

(a) Greenhouse operations must meet all applicable requirements of 

subparts B (205.105) and C (205.200 – 205.206) except that: 

(3) The producer operating a greenhouse with crops grown in 

containers is exempt from requirements of 205.202, 205.203(a). 

(4) In addition, the container based producer is exempt from the crop 

rotation and cover cropping requirements in section 205.203(b) and 

205.205. In lieu of crop rotation and cover cropping, soil 

regeneration and recycling practices shall be implemented and 

documented for the certification agent in order to demonstrate that 

the required functions of crop rotation and cover cropping listed in 

205.205(a,b,c,d) have been achieved through these alternate 

practices, as applicable to the operation. Specifically: 

(i) Maintain or improve soil organic matter content (a)- 

Examples include, but are not limited to, recycling and reuse of potting mixtures, addition of compost and other 
compostable materials,, earthworm replenishment, 

microbial re-inoculation, etc. 

(ii) Provide for pest management in crops (b)- Such as soil 

borne damping-off control through various low 

temperature heating methods and soil inoculation using 

disease suppressant bacteria and fungi. 

(iii) Manage deficient or excess plant nutrients (c)- Recycle 

excess plant nutrients contained in drain water from soil 

containers, avoiding so called drain-to-waste systems. 

Recycled nutrients must be re-used in the greenhouse, or 

alternatively, on a growing crop outside the facility. 

(iv) Provide erosion control (d)- Though erosion is not 

generally applicable to greenhouse production, recycling 

of drain water prevents off-site movement of nutrients, a 

common consequence of typical field erosion. 

 

(b) The use of potting mixtures containing prohibited materials is not 

permitted. 

 

a. Potting mixtures shall be recycled for re-use rather than disposed of 

as waste. 

b. Potting mixtures devoid of or deficient in organic matter capable of 

supporting a 

c. natural and diverse soil ecology are prohibited. For this reason, 

hydroponic and 

d. aeroponic systems are prohibited. 

(c) Producers may use full-spectrum light sources. 

(d) Plants and soil shall not be in direct contact with wood treated with 

prohibited materials that is used for greenhouse structures or frames of 

raised beds. 

(e) To comply with the provisions of 205.201(a)(5) to prevent commingling 

and contamination, organic and non-organic crops can be grown within 

the same structure only if the following conditions are met: 

1. An impermeable wall shall separate organic and non-organic 

production sites if prohibited materials are applied to the nonorganic crop to ensure that cross contamination does not occur. 

2. The ventilation system must ensure that prohibited materials do not 

drift, or are otherwise conveyed to the organic production area. 
3. Separate watering systems must be established if prohibited 

fertilizers and/or pesticides are injected within the watering system. 

4. Producers must ensure that no contamination occurs to the organic 

crop through cross-pollination with crops produced through genetic 

engineering. 

5. Soil mixing machines and other equipment used for non-organic 

crop production must be thoroughly cleaned prior to use in organic 

production, except that pesticide sprayers used in conventional 

production can not be used for organic production purposes. 

6. Adequate physical facilities, as determined by the certifying agent, 

shall separate organic and non-organic crops and production 

materials in storage, production or holding areas. 

7. Organic and non-organic crops and production areas must be 

conspicuously labeled. 

Addendum ANational Organic Standards Board 

Crops Committee 

 Soil-less Growing Systems 

May 2009 

This document seeks to clarify the NOSB Crops Committee position on soil-less 

growing systems, such as hydroponics, as they pertain to organic certification to 

the USDA National Organic Program standards. 

Introduction 

The organic farming method derives its name from the practice of maintaining or 

improving the organic matter (carbon containing) content of farm soil through 

various methods and practices. The reason this is the central theme and 

foundation of organic farming is not inherent to the organic matter itself, but is 

based on the importance of the organic matter to the living organisms that inhabit 

soils, particularly for its positive influence on proliferation of diverse populations 

of organisms that interact in a beneficial way with plant roots. These microscopic 

organisms, found in abundance in well maintained soils, interact in a mutualistic 

manner with plant roots, producing the effect of strengthening the plant to be able 

to better resist or avoid insect, disease and nematode attack, as well as assisting 

the plant in water and mineral uptake. The abundance of such organisms in 

healthy, organically maintained soils forms a biological network, an 
amazing and diverse ecology that is ‘the secret’, the foundation of the success of 

organic farming accomplished without the need of synthetic insecticides, 

nematicides, fumigants, etc. In practice, the organic farmer is not just a tiller of 

the soil, but a steward of the soil ecology on the farm, hence some of the 

alternate names for this realm of production, such as ecological or biodynamic 

farming. 

Discussion 

Observing the framework of organic farming based upon its foundation of sound 

management of soil biology and ecology, it becomes clear that systems of crop 

production that eliminate soil from the system, such as hydroponics or 

aeroponics, can not be considered as examples of acceptable organic farming 

practices. Hydroponics, the production of plants in nutrient rich solutions or moist 

inert material, or aeroponics, a variation in which plant roots are suspended in air 

and continually misted with nutrient solution, have their place in production 

agriculture, but certainly cannot be classified as certified organic growing 

methods due to their exclusion of the soil-plant ecology intrinsic to organic 

farming systems and USDA/NOP regulations governing them. 

The OFPA specifically required an organic plan designed to foster soil fertility 

(§6513b) and the NOP regulations resulting from the Act bear this out as follows: 

§205.203(a)- The producer must select and implement tillage and cultivation 

practices that maintain or improve the physical, chemical, and biological 

condition of the soil. 

§205.203(b)- The producer must manage crop nutrients and soil fertility through 

rotations, cover crops, and the application of plant and animal materials. 

§205.203(c)- The producer must manage plant and animal materials to maintain 

or improve soil organic matter content in a manner that does not contribute to 

contamination... 

Although the regulations do not specifically state ‘soil only production’, the 

exclusion of soil from organic production of normally terrestrial, vascular plants 

violates the intent of the regulations. This intent can be seen in these sections of 

the rule that require proper stewardship toward improving and maintaining the 

soil ecology within an organic farming system. It is pointed out that naturally 

aquatic plant species and non-vascular plant species such as mushrooms come 

from different (non-soil) ecological niches and would be handled separately. 

In previous Crops Committee discussion documents, the question has been 

asked: “Should container culture based growing media (typically utilized in 

greenhouse systems) that are predominately compost and compostable plant 

materials be considered ‘soil’. As highlighted in earlier portions of this document, 
a foundational principle of organic farming is the practice of maintaining and 

nurturing soil health so as to foster the proliferation of the proper soil biology with 

their accompanying ecologies. Since all typical soil dwelling organisms, such as 

earthworms, protozoa, fungi, bacteria, actinomycetes, etc. can thrive in a 

properly designed compost based growing media, producing the beneficial 

symbiotic ecological relationships found in soil, such growing media should be 

rightfully considered soil.