Effect of nitrogen fertilization, agricultural media, and pinching on the growth of geranium plants (Pelargonium graveolens L’Herit)

Abstract

This study was carried out in the Nursery of the Park’s Azade/ Sulaimanya city, from 15th Mar to 1st Dec 2012 to investigate the effect of nitrogen fertilizer (0, 150, 300) mg.l-1 nitrogen, planting media (river soil, peat moss, and soilless (manner, sawdust, hay, lawn grasses clipping) 2:1:1:1 by volume and plant Pinching (without, once, twice) on the growth of Geranium Pelargonium graveolens. The results summarized as follows, Fertilization of geranium plants with 150 and 300 mg.l-1 nitrogen caused significantly increased in plant height, branches number, leaves area, plant growth index, first cut of plants, in comparison with the control 0 mg.l-1 nitrogen. Soilless media had an equal effect of peat moss in leaves area, while the peat moss were significantly superior than the soilless in plant height, branches number and the soilless were significantly superior than peat moss in plant growth index, and the first cut of plant. Increased Pinching number decreased the plant height. On the other hand, it increased vegetative dry weight, first cut of plant when compared with non-pinch that gave the least values. Generally, the highest value for most characteristics like branches number leaves area, and plant growth index were found in twice pinching plants that fertilized with 300 mg.l-1 and planted in once and twice pinching.