Keep leaf colours fresh
As a rule, many plants with colourful foliage, particularly purples, do best in sun. In shadier spots they can become greener and, without light, the purples simply won’t show up as strongly. In these areas some of the most effective foliage plants are variegated ones, with white or pale yellow splashes showing up well against the green. Coloured foliage plants that have delicate leaves, such as Japanese maples or Sambucus racemosa ‘Sutherland Gold’, need a halfway house: dappled shade or protection from the hottest sun of the day. Another problem sometimes encountered with coloured foliage plants is reversion – when a plant reverts back to its parent’s original plain green. This is often seen in variegated cultivars or coloured phormium hybrids because the pure green form contains more chlorophyll, so is more vigorous and can soon take over the plant. Reversion is best tackled by promptly pruning out the affected parts completely or by cutting back into wood containing variegated or coloured foliage.