I guess when they are growing they are not dried flowers so the real title should be growing flowers for drying. As the display above shows you can get colour and texture into a bunch of dried flowers. The display is likely to last longer than a bouquet of fresh flowers and will be available when other material is expensive or in short supply.

There are 5 stages of development when a plant can produces flowers for drying.

1. In bud as colour appears, examples being Helichrysum (Straw flowers) and Ammobium ( Everlasting flowers).
2. As the buds open, with Echinops (Globe thistle), Eringium (Sea Holly), Lavender and Ornamental Grasses.
3. In full bloom, with Achillea (Yarrow), Alchemilla mollis, Gypsophillia and Alliums (ornamental onions)
4. After seeds have formed, like the Honesty in the bunch above and Antirrhinum, Poppy and Digitalis (Foxglove)
5. Just before the seed pods open, but after spraying with hair lacquer to prevent seeds scattering, Nigella and Scripus ( Bulrush)

The best way to dry flowers is to pick them  in mid morning when the dew has evaporated.

• Group them into small bunches and hang them upside down to dry.
• To preserve the colours, hang them in a dry well ventilated space with little or low levels of light.
• Large heads like Alliums and Artichokes need to be dried standing up. Make a chicken wire frame to separate and hold each bloom.
• Some stems may need wiring before drying either through a hollow stem or wound around the outer.
• Roses can be dried in a very slow oven for 5 hours or so. Pink varieties retain the best colour, red  and yellow roses go darker and white roses turn cream coloured..
• The leaves of large trees like Chestnuts, Limes, and beech can be ironed and they will retain colour.
• Delphiniums and Acconitums can be dried in a vase of salt; plunge the ridgid stems into slightly moistened salt.
• Dessicants can be used for delicate petals. Silica gel, borax or silver sand may be suitable for Carnations for example

‘Preserving Flowers: Dried and Pressed Floral Designs for Every Season’ by Diane Flowers (How appropriate)
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‘It all begins with dried blooms and foliage, a container or base form, a few tools, and a beautiful idea: the result is an elegant, long-lasting creation worthy of decorating any room. These projects reveal the possibilities for creating gorgeous pressed designs from a garden of silica- and air-dried flowers and plants. Discover just how simple it can be to amass a supply of dried plant materials using easy techniques for drying and pressing, and how to frame the flowers or embellish them with everything from candles to seashells. The exquisite items include wreaths, ornaments, displays, greeting cards, coasters, photo albums – even a scrapbook page.’