Care of Your New 'Catlin Contorted' Tree
What To Do Immediately
Carefully unpack your tree. It is very fragile and may wobble
in the
pot, so exercise extreme caution. Water the tree and place in a shady
location to recover from its journey. In most cases, it will not need
immediate repotting and it will be best to keep it in its original
container until the first opportunity to repot, usually fall or late
winter. At these times you can decide whether to repot. If you are
receiving your plant in the fall, wait until late winter to repot.
Watering and Fertilizing
Water your tree normally. That is, water when it
needs water.
'Catlin Contorted' grows at a frustratingly slow rate, so it will stay
wet longer than most of your other plants. Fertilize normally. If you
subscribe to normal soluble chemical fertilizer, then fertilize at
recommended full strength every other week.
Watching for Growth
Growth of 'Catlin Contorted' can be agonizingly slow,
sometimes only an
inch or two in a year, so don't expect big changes. As long as the
leaves are deep green and shiny, it is probably in good health. It
usually puts out a growth spurt in the spring. Sometimes this can be
surprising, and it may even grow an inch or two during this period in
some years. Other years it may only grow half an inch. It may or may
not have another growth spurt in late summer. This slow growth and its
exceedingly tiny leaves and internodes make it an ideal candidate for
mame bonsai. Indeed, you will be hard pressed to get it to grow fast
enough for any other size bonsai.
Light
Don't let the fragility of this species fool you. It is a
light lover
and requires very high light requirements. In most cases, it can be
grown in full morning sun and afternoon shade with no problem. In very
hot and dry climates, it will probably be best grown under about 30 to
40% shadecloth, but early morning sun/ afternoon shade may still be
acceptable. It doesn't acclimate to new locations very well, so
whenever making a change, do it gradually and slowly. Always start out
at lower light levels and move to higher until you get maximum growth
without problems.
Indoor Growing
Forget it. In most cases, unless you are highly experienced
in growing
temperate climate plants indoors, it will most likely succumb in indoor
conditions. The only exception to this is if you have no
proper
overwintering location, you may be able to keep it inside for a few
months in winter until it can be returned to its outdoor location in
spring, but this is not recommended.
Dormancy and Cold Hardiness
This is a sport of Ulmus parvifolia 'Catlin' and will behave
in a
similar fashion in regard to winter weather. It is a semi evergreen
cultivar that is reluctant to lose its leaves in winter. It may have a
slight yellow winter color, but most often the leaves just turn brown
and fall off. I have overwintered it in a cold greenhouse (that never
freezes) and in the open where it does freeze, but the temperature does
not fall below about 25F. It remains evergreen in the cold greenhouse,
but it performs better in the open where it is allowed to freeze and
lose its leaves. In spring, leafless plants rebound with nice new green
leaves and a healthy growth spurt. Cold greenhouse overwintered plants
tend to sulk in the spring and don't want to break into new growth.
In cold areas (zones 7 and colder), it is probably best to
overwinter with your other plants in a garage or other structure where
the temperatures can be kept between 20 and 40F for most of
the
winter. 20F in a sheltered structure will be perfectly safe
for a
properly hardened off plant.
Hardening off should be accomplished normally. That is, allow
it to
stay outside and experience at least a few mild freezes before and
night temperatures in the 20's F before placing it in the overwintering
structure. In zones 8 and above, just leave it outside through fall and
early winter to harden off naturally. If temperatures threaten to fall
below 20F, then some protection is required. I use the irrigation
system to apply water to most of my smaller containerized plants on
freezing nights in winter. This encases them in ice and keeps the
temperature from falling below about 25F, even when the ambient
temperature is 15F. This will also prevent freeze drying, which is
common for such small containerized plants.
Root Work and Repotting
I am still working out the fundamentals of root work for this
cultivar.
It's tendency (and that of 'Catlin' as well) is to produce one or more
long thin primary roots and almost no lateral roots. This is a
maddening habit for creating bonsai. Often these roots will be a foot
long on a plant that is only inches tall. On a plant that is so slow
growing, the tendency to just let it grow without root pruning. This is
probably a mistake. It is most likely better to root prune and repot
every year eventhough the roots will nowhere near fill the pot in a
single year. This will allow you to continually trim back the long
primary roots and encourage lateral roots instead of just letting the
long primaries grow and severely traumatizing the plants with a radical
cut back every years. This will also eliminate the problem of soil
collapse if you use any organic materials. Since the roots never
colonize the pot, the medium stays wetter than normal and the organic
amendments will break down in a year or less. Using an all inorganic
soil will help with this, but won't solve the problem of long roots, so
it will still need yearly root pruning. I have grown it in 100% Profile
(Schultz's) and have not seen any better performance than in my
bark/perlite mix.