•Flower from mid to late autumn when few other perennials flower.
• Fill a large space in the garden.
• Many of the best new varieties available here have been bred in New Zealand by our own expert, Dr Keith Hammett.
•Deciduous, so the foliage dies away completely over winter and returns afresh.
• Easy to grow in good conditions which don’t get too dry over summer.
You do need space for these late autumn beauties and they will be badly affected by heavy frosts.
But if you have a suitable position, they are an easy-care delight. These two varieties are both from the breeder, Keith Hammett and alas we no longer have the names. The big, floppy pastel lilac is so pretty against our shed and I thought at first I was looking at a clematis from afar (it is about 2 metres tall). The golden orange sunburst bloom (love the slightly twisted petals) is a little more compact (a little shy of two metres) and has delighted us for a number of years, planted as it is by the mandarin tree whose fruit are colouring to match.
They are not called tree dahlias because they grow up like a tree but rather because they grow much larger than the usual type of perennial dahlias. In windy conditions they need a bit of support – some of ours we fence in with heavy duty bamboo cross bars. Otherwise, they are like any other dahlia with typical hollow stems and dahlia leaves, growing in a large clump from tubers below ground. Most tree dahlias come from D. imperialis which is native to Columbia and Guatemala which explains why they are not keen on cold and frosty conditions.