The mostly used species
is Ulmus parvifolia with its very small, dark green brilliant leafs.
Depending on the climate the leafs are permanent or will fall late in
winter after showing a beautiful orange color.
much light, likes inclusive direct sun exposition.
Temperature and exposure:
They can be raised in interiors but should pass a fresh winter. Elms
support cold winters against the opinion of lots of specialists. I have
had even a little snowfall on them, without loosing any branches.
Pruning and cleaning:
I remove the dry leafs in autumn because they don't fall very easily
on their own. During the vegetative phase which is very intense, be
sure to prune the long branches to avoid big distance between knots.
This way ramification is assured. Leafs can be removed in June, but
normally it isn't necessary because the leafs are quite small anyway.
When summer ends, structure pruning should be done to prepare the tree
for the colder seasons.
much wiring is done on the elms, only when the tree is young to form
the main branches. Wire at the end of june and remove the wire in october.
Form is mainly given by continuous pruning.
prefer high humidity, vaporize often. In summer they need a lot of water
but be sure to have a good drainage.
Repotting / Soil:
Should be done between spring and summer every two years into a bigger
pot. Cut around 2/3 of the roots. The mixture I use is 2/4 compost,
1/4 humus and 1/4 sand. I like the blue ceramic pots, normally rectangular.
be applied during spring and autumn but not in summer. Never use after
repotting. I prefer the solid type which dissolves itself when tree
are not very sensible, but if the atmospheric humidity is not high enough,
red spiders will attack the little leafs turning them dry in a short
time. Shower the tree a lot of times during the day because water is
the worst enemy of the red spiders. If that doesn't help apply Compo
anti red spider mite.