So OK,

the foliage of Canna 'Durban'(syn. 'Phasion'; 'Tropicanna') is striking red, in my garden, but is rather an ugly mixture of green and darker green in that of my friend.

She has a very wet garden (Northern - Holland), heavy clay, this for several years.

My canna's are in thubs, with a mixture of ground from the garden (heavy clay, wet), and normal ground for plant (bought in shops), sometimes with special ground for waterplants. Early on all canna's where given extra food (for waterplants), so also hers.

If it's caused by antocyanin, then the soil has to have some kind of minerals for the plant to be able to produce this antioxidant pigment. Photosynthesis, UV-light, Streptomycin, aluminium seem to play a role.

The effect of anthocyanin is also influenced by the acidity. I think I see the wrong!!! effect in my garden: Canna 'Endeavour' bloomed rather blue-purple in the bassin majorly filled with rain water (so more acid), then in the thubs with a ground mixture of heavy clay and every-day ground for plants. There it bloomed reddish.

But, in these thub I also grew Valeriana officinalis, which I know to have a rose blush in some locations (my former garden,wow!), and it blooms completely white in other. Then, it should have some rose colouring! But no, it stayed white.

So, has anyone a clue on what is different between my friend's garden and mine? Both are rather wet, contain a large amount of clay.

Perhaps mine has more useful minerals? Perhaps the plant-food I'm giving (for waterplants) has it? She gave other plant-feeding.

And I think, nutrition for Hydrangea could be the answer for striking red foliage in C. Durban.

Thanks,

Hugo