There are a few institutions in Israel which offer MSc programs in agriculture sciences (which include plant sciences) to international students in Israel, among them: The Ben Gurion University of the Negev in Beer Sheva, The Weizmann Institute of Science in Rehovot and The Hebrew University in Jerusalem. In order to apply for an Master in agriculture in Israel all candidates must finish their first degree in biology, biotechnology, agriculture, animal sciences, food sciences or any of the related fields with a GPA of 80 or more. In cases students are not from an English speaking country, they will have to take an English proficiency test like TOEFL or IELTS. Candidates must submit three letters of recommendation, and relevant experience is the field of agriculture. Each institute offer different scholarships and financial aid program so you'll have to contact them separately to get all the information you need.
In The bottom of my message you can find a link, once you'll click it it will send you to an article about the different programs you can choose from and more information about the admission, institutions and more.
For information about the cost of the program you'll have to contact the university in which you wish to study directly.