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The pH in the cultivation of orchids

      _cc781905-5cde-3194-bb3b-136bad5cf58 abbreviation of the term Hydrogenid_ Acidic or alkaline is this a solution.  It works like this: hydrogen (H+) is responsible for determining the acidity of a solution, that means that the more H+ a solution has, the more acidic it is. On the opposite side is the hydroxyl radical (OH-), which, in a solution, the more OH- there is, the more alkaline it will be, 

      _cc781905-5cde-3194-bb3b-136bad5cf58 is the scale from ph0 to 7d ranging from 1 to 7d , representing neutral pH. The closer to 0, the more acidic and the closer to 14, the more alkaline. 

       Veja abaixo um exemplo de pH de algumas soluções conhecidas:_cc781905-5cde- 3194-bb3b-136bad5cf58d_

      _cc781905-5cde-3194-bb3b-136bad5cf58 in cultivation.  Normally the amateur orchidist uses whatever water source is available to irrigate the orchids, without worrying about its characteristics, a fact that is the very difference between success and failure in cultivation. Over time we learned that irrigating plants with rainwater is better than using tap water, but in practice, this means that it is better to use water with a pH of 6.4 than a water with a pH of 7.2 to water the orchids.

         O primeiro impacto a ser observado it's about nutrition. Different pH levels affect what we call nutrient availability for the orchid. In practice, this means that it is not enough to fertilize your plant, but you also need to assess whether the pH of the substrate   in which it is planted will allow these nutrients to be absorbed and used by the plant. 

         Na natureza as orquídeas são irrigadas with rainwater, which is usually very pure (with the exception of places with a lot of pollution). Rainwater is usually slightly acidic, with a pH between 6.4 and 6.8. 

          _cc781905-5cde-3194 -bb3b-136bad5cf58d_But it's not just the water that matters when talking about pH, we must also look at the substrate in which the orchids are planted.   If you are using an organic substrate, for example, this will naturally make the environment more acidic. In these conditions, some micronutrients find an optimal condition for absorption, and can easily become toxic for your orchid. In these cases, raising the pH of the solution used for irrigation will bring fantastic results for your crop. 

       Alguns fertilizantes utilizados na fertirrigação (Mono-Amonio-Fosfato (MAP), monopotassium phosphate (MKP), phosphoric acid, nitric acid, and ammonium sulfate),  tend to acidify irrigation water.   Others  (potassium nitrate, calcium nitrate, mannaturezagnesium nitrate and potassium sulfate), tend to alkalinize it. That's why  the need to know the reaction of fertilizers dissolved in irrigation water irrigation, avoiding losses in the production growth (quantity and quality) of flowers and the loss of nutrients due to formation of precipitates: Loss of calcium (Ca) and magnesium (Mg) in the form of calcium and magnesium carbonate; sulfur (S) in the form of calcium sulfate; phosphorus (P) in the form of calcium phosphate and iron (Fe) in the form of iron sulfate.

In practice, nutrient solutions for fertigation can be classified into three categories: Optimal (5.5 <pH ≤ 6.5), suboptimal (6.5 <pH ≤ 7.5) and insufficient (pH > 7.5 ) .

      _cc781905-5cde-3194-bb3b-136bad5cf58d table below shows optimal absorption point the pH (optimal range between 5.0 and 6.5)


efeito do pH na adubação nutrição orquideas

      _cc781905-5cde-3194-bb3b-136substrate growth, activity and pH_d second place microorganisms contained therein. And we know that there is a strong relationship between certain microorganisms that develop along the roots of orchids and the availability of nutrients for them. 

      The pH also affects the efficiency of the pesticides used!

         A maioria dos defensivos agrícolas tem an ideal pH for greater effectiveness, both in terms of efficiency and also in terms of time of action in the crop.   This is also one of the reasons for not mixing different pesticides: in addition to being able to react with each other, generating loss of action or even toxicity to the orchid, each pesticide has an ideal operating range._cc781905 -5cde-3194-bb3b-136bad5cf58d_

      _cc781905-5cde-3194-bb3b-136bad5cf58d The tables show the ideal pH_ for most products available below in the market. The table describes the active principles without mentioning the commercial name. Therefore, for your research, see the name of the active ingredient on the product leaflet and find it in the tables. 

Efeito do pH sobre acariscidas acaros orquideas
Efeito do pH sobre Inseticidas insetos  orquideas
Efeito do pH sobre fungicidas fungos Orquideas
efeito do pH sobre os herbicidas Orquideas
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