The RHS explains deadheading can also prevent plants with numerous petals, such as peonies, some camellias and many roses, scattering debris widely.
You don’t have to dead your flowers, however, doing so will encourage new flowering stems to emerge.
Some plants don’t need deadheading. For example, fuchsias, bedding lobelia and salvias either don’t set much seed or neatly deadhead themselves
While taking a pair of shears to your plants may seem daunting, there are some simple tricks to pruning without causing damage to your plants.