EFFECT OF PLANTING DATE, PLANT SPACING AND CLOVE SIZE ON GARLIC (Allium sativum L .) YIELD UNDER SEMI-ARID CONDITIONS IN JORDAN

A field experiment was conducted in 2006/2007 growing season at the Agricultural Research Station, Mu'tah University, Jordan, to study the effect of planting date, spacing and clove size on garlic yield. A factorial combination of three planting dates, three plant spacings and three clove sizes were laid out in a randomized complete block design with three replications. Results indicate that early planting date (Nov. 15) produced higher yield, average bulb weight and clove number per bulb. Close spacing of 10 cm resulted in significantly (P< 0.05) higher garlic bulb yield. Moreover, using large cloves gave the highest yield compared with medium and small cloves. Number of cloves per bulb and bulb weight were mainly affected by planting date. However, plant spacing and clove size had little effect on these parameters in each planting date. Maximum bulb weight (54.62 gm bulb -1 ) was produced when large cloves (2-3 gm) were planted on Nov. 15 at 20 cm plant spacing. In conclusion, to produce the maximum yield, large garlic cloves should be planted early in the growing season with 10 cm spacing.