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Mist Applications of Sodium Silicate to Rose (Rosa L. × ‘Nearly Wild’) Cuttings Decrease Leaflet Drop and Increase Rooting

Jeffrey H. Gillman1 and David C. Zlesak2 Department of Horticultural Science, University of Minnesota, St. Paul, MN 55108 Received for Publication 25 Aug. 1999. Accepted for Publication 1 Dec. 1999. Minnesota Experiment Station # 981210039. The authors would like to thank Erica Davis and Robert Ford for technical assistance. The cost of publishing this paper […]

Orchid Culture Sheet

Cymbidium Light and Temperature: 2,000-4,000 foot-candles. Cymbidium orchids may be grown outdoors in areas where heavy frost does not occur. They need filtered sunlight or full sun for half a day and good air movement. Foliage will be slightly yellow green, not dark green. Cymbidiums withstand a great deal of heat and cold. Night temperatures […]

Enzymes: The Workhorses of Life

Enzymes are proteins which are involved in increasing the rate and efficiency of biochemical reactions. Most enzymes require metal ions for activation and function. Without proper enzyme function, growth would cease in an organism. Most of the essential mineral elements affect enzymes in multiple ways.

pH: What Does It Mean?

The term pH refers to the alkalinity or acidity of a growing medium water solution. This solution consists of mineral elements dissolved in ionic form in water. The reaction of this solution whether it is acid, neutral or alkaline will have a marked effect on the availability of mineral elements to plant roots. When there […]

CEC or Cation Exchange Capacity

The Cation Exchange Capacity refers to the ability of the growing medium to hold exchangeable mineral elements within its structure. These cations include ammonium (nitrogen), potassium, calcium, magnesium, iron, manganese, zinc and copper. Peat moss and mixes containing bark, sawdust, and other organic materials all have some level of cation exchange capacity.

The Mineral Elements In Plant Production

The use of soil for greenhouse production before the 1960s was common. Today a few growers still use soil in their mixes. The bulk of production is in soilless mixes. Soilless mixes must provide support, aeration, nutrient and moisture retention just as soils do, but the addition of fertilizers or nutrients are different. Many soilless […]