The short answer
Late March to early April for cherry blossoms · Mid-to-late November for autumn leaves.
Kyoto's two crown seasons are short, intense, and crowded. Both are famous for a reason — few cities in the world are as photogenic in their peak weeks. Plan accordingly.
What's different about Kyoto's climate
Kyoto sits in a basin surrounded by mountains. This makes summers noticeably hotter and stickier than Tokyo, and winters slightly colder. Autumn leaves peak about a week later than Tokyo because the basin holds warmth into early November.
The Gion Matsuri factor
If you visit in July, you'll likely overlap with Gion Matsuri — Japan's most famous festival. The Yamahoko Junko parade on July 17 is genuinely spectacular. But mid-July Kyoto is also peak heat (35°C+ humidity). It's a tradeoff: festival energy vs. weather comfort.