How colours relate to each other is best illustrated in the colour or spectral wheel.

First, there is the harmony of adjacent colours. If blue is a dominant colour, for instance, then blue mixed with green and blue mixed with purple will harmonise.

Second, there is the contrast of opposite colours: yellow with purple, orange with blue, red with green...

Thirdly, there is the harmony of triads. For example, if one takes yellow as the initial colour, then the triad harmony colours are red and blue.

As with every guideline, principle or rule, the spectral wheel should be followed with care. For instance, the three primary colours, if used in their most dominant forms, will overpower any other colour included with them, even if those colours are related in some way on the wheel. For that reason, modern planting practice favours the more subtle pastel shades.

Psychologically, the colour blue is cold, yellow is thoughtful and red is violent. It is advisable to keep these colours together with white and black closest to the house, with the very light pastel colours towards the end of the garden to provide an illusion of extra length.

All the plants who have flowers in in the Plant Photographic Galleries of this website will have their Common Name, Botanical Name and Months of Flowering in one of the 52 colour index pages in the Colour Wheel Gallery (Each of the 12 Colour Sections has been split into 4 Colour Groups plus Black, Gray234, Gray 5 and Pure White 6 in the Black Colour Section). The Common Name will be in Red if it is a Wildflower, The Botanical Name will link to its Plant Description Page and each Flower Month will link to the respective Flower Colour Comparison Page in the relevant Gallery.

If the Flower Petal is Multi-Coloured, then it will be placed in the Multi-Coloured Row of a Colour Wheel Colour Page that appears to have the majority space of that colour on the petal.