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Credit: Carol Sharp

Unfurling like red flags, the new leaves of many evergreen shrubs herald the arrival of spring. This burst of colour – think of Fraser’s photinia or Pieris japonica cultivars – adds a splash to the garden, but more importantly to the plants, it helps ward off hungry insects looking for a tender meal. Botanists at the University of Chicago analyzed data from hundreds of trees and shrubs and found that 62 per cent produce pink or red new leaves. Insects cannot see red leaves as well as green leaves, so the red flush acts as camouflage. Pests may also be tricked into perceiving the new leaves as tough, old leaves that have turned red for autumn.