A field experiment was carried out during the two successive winter seasons of
2014/2015 and 2015/2016 at a private farm in El-Tour region, South Sinai Governorate, Egypt, to
study the effect of planting dates, nitrogen sources and their interactions on dry weight, yield and its
components and nitrogen use efficiency (NUE) of garlic (Balady cultivar) grown in sandy soil conditions
using drip irrigation system. The obtained results could be summarized as follows: The interaction
between planting dates on 15th Oct. or 1st Nov. and fertilizing plants with 100% of the recommended
rate (RR) of N as poultry manure (PM) or and 50% RR of N as ammonium sulphate (AS)+50% RR of
N as PM gave the highest values of each of dry weight of bulbs, leaves, and total dry weight/plant at
135 days after planting (DAP), N and P uptake by bulbs and leaves and total uptake of them by plant,
yield of grades 1,2, exportable, marketable, total yield, average bulb weight and the highest values of
nitrogen use efficiency (NUE). Whereas, the interaction between planting on 15th Oct. and fertilizing
plants with 50% RR of N as AS + 50% RR of N as PM gave the highest values of K uptake by bulbs
and leaves as well as K total uptake by plant.