Job offersmore »
- Technical Sales Representative Trainee - Ancaster, Ontario
- International Account Manager City Farming - Horticulture LED Solutions
- CEO for a leading Agri-Business working on an international basis
- Greenhouse Operations Lead - Alberta, Canada
- Commercial Head Grower - Newark, NJ (USA)
- IPM & Pollination Specialist (ornamentals) - Western Europe
- Regional Sales Manager - USA
- General Manager Operations - Australia
- International Account manager Horticulture LED Solutions - Netherlands
- Plant Specialist Horticulture Northern Europe
Last commentsmore »
- India: Government gives 50% subsidy on a poly house (673)
- Dutch grower supplies plants to world's biggest cruise ship (27)
- Terra Nova Nurseries introduces heat-loving heucherella variety (25)
- For sale: 10 brand new Cummins natural gas generators (16)
- "Plum Power forever" (17)
- Milestones, lessons from California’s historic drought (24)
- Kenya: Rimi Flora to triple in size (1)
- How can we make millennials purchase flowers again? (1)
Top 5 - yesterday
Top 5 - last week
Top 5 - last month
Exchange ratesmore »
Relationship between fertility extremes and growing medium pHThe pH of a growing medium increases or decreases depending on the fertilizer used, the crop grown, and the water alkalinity. However, pH change is usually gradual. When fertility levels in the growing medium are either very low or excessive, the pH of the growing medium can change rapidly. When the fertilizer level is very low in the growing medium (measured as electrical conductivity (E.C.)), there is a rapid increase in the growing medium's pH. Likewise, when the E.C. of a growing medium becomes excessive because of a potentially acidic fertilizer, the pH drops. So why does this happen and is it a concern for the crop grown?
Low Fertility = Higher pH?
Typically, when a crop is grown in a growing medium where the overall fertility level is very low (E.C. is below 0.3 mmhos/cm), the pH tends to increase rapidly by approximately 0.5 pH unit. This can be seen in Figure 1 on days 8-10, when the pH rose from 5.8 to 6.5 as the E.C. dropped below 0.3 mmhos/cm. However, if the same growing medium with the same crop is fertilized more frequently so the E.C. does not drop below 0.5 mmhos/cm, the pH changes very little. The phenomenon of sudden pH climb due to low E.C. often occurs when growers feed at very low rates, withhold fertilizer to minimize plant growth or simply do not feed at all. It is believed that this occurs because the plant has few fertilizer elements to take up from the growing medium that can generate acid through the roots. In addition, the water alkalinity and limestone in the growing medium work together to also increase the pH of the growing medium.
Read more at the PRO-MIX website
Publication date: 1/10/2017
Other news in this sector:
Leave a comment: (max. 500 characters)
- All comments which are not related to the article contents will be removed.
- All comments with non-related commercial content, will be removed.
- All comments with offensive language, will be removed.