Promptly removing faded flowers not only smartens up the appearance of pots, hanging baskets, border perennials and shrubs, but also stops the plants being able to turn that flower into a fruit, expending energy on needless production of seed.
Instead, that energy will go into creating more flowers and if you keep deadheading those, the cycle continues – essentially, you’re tricking the plant into producing more and more flowers, which means more colour for you!
Some plants practically pack up the moment a seed head is produced – sweet peas for example – so your vigilance really will be well rewarded.
Make it a regular job at this time of year, going round the garden with snips and a bucket for the dead-heads each morning or evening, to catch any spent flowers before they have a chance to mature.
Others will carry on producing flowers if you leave a few dead ones on – pelargoniums, petunias – but can look messy if their new flowers have to jostle alongside browning flower stems.
Their subsequent flowering will be much better if the dead blooms are removed, and you’ll also reduce the risk of fungal disease, such as botrytis, infecting the dying tissue.
Different plants need different techniques, depending on how they flower and the length of their stalks and stems.
HOW TO DEADHEAD
Remove whole stalks from plants such as hemerocallis, rather than just the dead flowers at the top. Cut right back to the base for a neat tidy finish.
Plants such as cosmos just need to have individual faded flowers removed, cutting back to a main stem from where more flowers will be produced.
If early flowers such as polemonium hardy geraniums and foxgloves are deadheaded - cutting back quite hard - they'll often go on to produce a second flush.