Chinese snowball is one of spring's showiest shrubs. White flower clusters 6 to 8 inches across festoon its branches in late spring. The plant gets big—12 to 20 feet tall and wide. Though it looks like a hydrangea, it's actually a viburnum.
Tulip 'White Dream': produces bowl-shaped blooms on 45cm stems in April and May. Plant in a pot at the front of the border and ring the changes through the year with crocus, alliums, lilies and agapanthus.