Nyssa - Growing Guide
Growing Nyssa
Commonly known as ‘Tupelo’
Nyssas originate from both China and the USA. They have small insignificant greenish male and female flowers on the same tree in summer followed by ovoid blue-black fruits which hang down and contain one ‘stone’ or seed.
At first glance at the leaves on those small trees growing quite slowly at Caerhays you might expect them to be evergreen. However it is the spectacular autumn colour for which these trees are grown. Improved forms with even stronger autumn colours are coming onto the market. N. ‘Wisley Bonfire’ well merits its name and we hope to be offering this soon having tried it out for ourselves.
In Cornwall, with our high rainfall, strong winds, and lack of autumn frost, we seldom see the displays of autumn colour which are enjoyed in the eastern counties. As one of the absolute best exponents of autumn colour nyssa can be enjoyed to the full in colder, drier counties than ours.
N. sinensis, the Chinese Tupelo, grows eventually to around 30ft. Its autumn colour is a brilliant mixture of orange red and yellow. With us red predominates. This tree, despite pruning, seems determined to grow more than one leader and is likely to end up as broad as it is tall.
N. sylvatica, the Black Gum, grows rather taller and can reach 50-60ft. The leaves turn a vivid orange, yellow or red. We grow this tree in dappled shade which it seems to enjoy.
N. aquatica, the Cotton Gum, is less well known in cultivation but can become the largest of the three species. As its name implies it grows in boggy waterlogged areas of the Mississippi and our tree is probably slow growing because it is in too dry a position. The autumn colour with us is yellow and appears late into the autumn.
If your trees are old enough to set seed these can be propagated in the cold frame. We have found cuttings difficult and should perhaps take them earlier in the year.