The most beautiful time of the year in the Kathmandu valley is April-May. Not only numerous flowers are in bloom but many trees, big and small, are also blossoming. One of my favourites - jacaranda. Its violet flowers cover the whole tree.
And this tree is also big and exotic - silky oak (Grevillea robusta). It is popular for roadsides being both attractive when in flower and aslo evergreen, giving some shade all the year round.
The next one is solandra. Its flowers are big (around 20 sm in diameter)and beautiful.
And such unusual looking flowers belong to Pink Siris.
Orchid tree, called here in Nepal Koiralo. The flowers are sold in markets for making chutney.
Coral tree, or Erythrina, has very beautiful bright red flowers. Their petals are very unequal that gives the flower an unusual shape.
And of course, Rhododendron, the national flower of Nepal.
See also The Sacred Pipal and Amazing trees of Nepal