My simple rule is that I feel hot colours work best in bright sunlight and cool colours are useful and brighten up shade more so than bright colours.Its all to do with light.There is no such thing as colour only light reflecting off surfaces.
If you need help deciding what colours you might like to play with and also that you like it may be useful to familiarise yourself with the colour wheel.
Follow my any colour wheel; It simply illustrates that colours close together harmonise and are calm and colours opposite contrast and may be striking and dramatic.
Hot Colours
This is hot colour suitable for a sunny position. It would look garish in the shade. Orange, red, Burgundy, purple and yellow for contrast and naturally green is also involved as foliage. I have also added lysimachia acid yellow foliage. Geraniums mix with purple and lime nemesia trailing purple petunias, some of the new Summer trailing petunia (yellow fading to orange). The trailing verbena is purple. There is also a little bit of white bacopa. I have also added orange diasica and begonias to trail not in the photo. This arrangement will get noticed.
Soft Tones And Harmonising Combinations
Purple tones. Purple Twister is one of the the newer trailing verbena in the front of the picture. It is combined here with purple nemisa, pink nemisa, white geraniums and lavender blue trailing petunias.
The classic combination of pinks blues and mauve with white and though its not visible silver foliage.
Harmonising Yellow
Its not just pinky purple tones that harmonise. Oranges and yellows can look brilliant. This yellow is an ideal colour combination in a cool corner and an excellent example of how we can harmonise different shades of a bright colour to provide a calm feel. Lime nemesia again with lysimachia foliage and yellow trailing bidens with specs of white petunia and geranium.
Soft Pastels
Pink silver and white using pink nemesia which stands upright a white geranium and trailing silver nepeta.
Pastels in the form of soft pink petunias and lime nemesia combined with white bacopa.
Abandon The Rules With A Mix Of Bright Colours
I think with so much green to soften the colour pallet that when we ignore all rules on colour and just combine a mad mix of everything bright we still get away with it. We should always find ways to break the rules and often when doing so we come up with a colour combination tat is outstanding.
(pot 1)This dynamic pink has something a little bit orange about its tone and therefore blends with yellow its not a bluey mauve pink. Many pinks are quiet repugnant with bright yellow but this is my exception and I expect it is something to do with the tone of colour, just as mixed shades of pastels appear to work.
Containers
Pot 1)
Pot 2)
Shades of burgundy (deeper than the image suggests), purple heliotrope (center) and lavender highlighted with soft lime.
Pot 3)
Purples burgundy and silver. The center is an osteospermum or cape daisy.
Choosing plants for a pot, container or hanging basket can be a little overwhelming with such a huge choice of both plants and colour.
Plant combinations in pots can be fabulous but I equally enjoy simple pots planted in all one colour or all one plant such as red geraniums or colourful salvias or dahlias or a pot of white marguerite daisies so don't be daunted successful colourful pots are easy to create.
More Help With Summer Pots And Baskets On This Gardening Blog
How To Plant A Hanging Basket