Whatever annuals you choose to grow there are several ways to get the best from them in your garden.

Control Annual Seeding

• Annual plants raison d’êtra (reason for being) is to procreate and help the species survive. Use this to your advantage by stopping your annuals setting seed. If annuals set seed it is a sign the job is done and flowering will stop.
• Pick flowers for indoors, Sweet Peas can be picked every day to encourage new flowers and prevent early demise of the plant. Alternatively trim, deadhead or shear off old flowers as they go over but prior to setting seed to get a new flush of flowers.
• If you wish to collect seed for next year wait until late August when plants will begin to stop producing new flowers anyway as the days get shorter.
• Water and space are probably more important than feed. Some plants like poor soil to encourage flowering, Nasturtiums for example will produce a lot of leaf if the soil is too rich and fewer flowers.
• Cut off flower heads of annuals you do not want to crop up everywhere. Teasels, Honesty, Welsh Poppies and  Bellis Daisies seem to get everywhere in my garden.
• Pull out old plants and compost them when you have finished with them. Replace with some biennials for a quick show next spring or plant up some late flowering Asters or Chrysanthemums.

Remember some plants may be half-hardy perennials, like the Antirrhinum  but are best treated as Annuals and should be grown for one flowering year only. Annuals make good cut flowers and have a fast range of colours from which to choose.

Other Resources

Royal Horticultural Society RHS ‘Gardening for All’
National Council for Conservation of Plants and Gardens ‘Conservation through Cultivation.’
Garden Organic National Charity for Organic Gardening.
BBC Gardening
Buy Daisies and other annuals as seeds and plants at Thompson & Morgan