which quality marks exist?

the quality marks RHP Horticulture and RHP Mushrooms are relevant for Horticulture

RHP Horticulture
This quality mark for substrates offers more security to growers of flowers, plants, vegetables and fruit. The RHP Horticulture quality mark guarantees the quality of the substrate in the chain from production to processing at the company of the grower. Growers increase the security that the substrate complies with the various quality requirements, like:

• Control of (disease)risks
• Assurance of agreed physical specifications, like water and air content
• Assurance of agreed nutrient aspects, like EC, pH and N-P-K

In short, growing media that comply with the wishes of the culture.

Control of risks
Substrates and raw materials that carry the quality mark RHP Horticulture, must comply with a large number of phytosanitary requirements. The products must be clean and pure, so that there is no risk for the application in the culture. That already starts at the raw materials. When they are pure, then they have to stay pure in the production process at the substrate supplier.

An RHP-product among others complies with the requirements below:

• Use of peat from areas where no agricultural activities have occurred. Contamination must be prevented and mixing during production is out of the question. This, combined with strict logistic control prevents the risk on a potential contamination.
• Weeds that could cause problems in a culture and/or in a country are not allowed (for instance tropical origin, invasive exotic plants).
• Organisms that are a risk for the culture are not allowed (for instance plant parasitic nematodes).

Securing physical specifications
RHP develops actively new parameters to assure you that RHP certified substrates guarantee the basis of an optimal culture. Nothing may be left to chance! There is a number of internationally recorded methods to analyse physical (and chemical) properties. However insight into a larger spectrum of properties is required.

New parameters which RHP develops, are for instance:

• Recording the biological stability.
• Water uptake and the WOK method (WOK = water uptake characteristic). With this method it is tested how quickly a dry substrate absorbs water.
• Specification on air content.
• RHP develops tools to adjust the potting soil better to the potting situation.

Securing nutrient aspects
RHP Horticulture provides insight in the chemical properties of substrates. The property of a substrate is closely connected with the kind of use and the plants that grow in it. Is it about lettuce plants, bedding plants or orchids; every plant has its own wish list. The acidity is important, but also the (trace)elements. The RHP quality mark puts requirements to the raw materials and the composition of additives (for ex. fertilizers) that are added to the substrate.

RHP puts high requirements to the composition and the quality of fertilizers:

• The composition of basis potting soil fertilizers has come about, based on scientific research and practical experience. All this has lead to the current composition, including a necessary and safe level of trace elements.
• Specification of pH, EC and assessment on N-P-K. Soil samples from practice and from substrate companies are analysed at RHP acknowledged laboratories. Then the information is assessed in the database of RHP, named Minerva.
• The RHP product may not fall outside the scope of legislation, as is applicable in the country of production and processing.
• Controlled release fertilizers (release pattern with specification ‘early - mid - late').