The Messenger of Allah ﷺ commanded to estimate vines (for collecting zakat) as palm-trees are estimated. The zakat is to be paid in raisins as the zakat on palm trees is paid in dried dates.
أَمَرَ رَسُولُ اللَّهِ ﷺ أَنْ يُخْرَصَ الْعِنَبُ كَمَا يُخْرَصُ النَّخْلُ وَتُؤْخَذُ زَكَاتُهُ زَبِيبًا كَمَا تُؤْخَذُ زَكَاةُ النَّخْلِ تَمْرًا