by Lis Friemoth
Bring living trees indoors for holidays (but not too
long)
Although Christmas tree farms produce renewable crops,
and many artificial trees are now recyclable, the idea
of using a live tree to celebrate the season can warm
the freezing garden soul.
With a bit of planning and care, you can enjoy a new
tree or plant for the holiday season, and after the festivities
have come and gone, for a long grow in the home or landscape.
One of the most important planning steps in choosing
an indoor live tree or plant is to decide on the ultimate
end use. If you only want a living tree or plant for
the duration of the season and have no intention of planting
it outside — there is no need to be overly concerned
about what species and cultivar you are choosing. Buy
something that makes you happy and plan on a trip to
the compost pile after it has died. But if you are looking
to use that live plant either indoors or for the outdoor
landscape, you will want to get the most out of that
choice.
Look for species that survive in colder climates or
in appropriate indoor conditions. Don’t forget to check
out the unusual, such as evergreen fruit trees. Satsuma
tangerines, Meyer lemons, and lime trees all make great
houseplants that can be moved outside in early summer.
For those live tree purchases, there are a few things
to consider: choose a species that is hardy for the climate;
ball and burlap or container plants will work best. Dig
the planting hole (reserving the soil in the garage or
shed) before the ground freezes solid. Allow enough space
for the plant to spread nicely as it matures, and water
it in well when planted outside. Always of concern is
how to handle the tree indoors and out so that it sustains
the least amount of damaging stress.
A few days prior to your holiday celebration, move the
tree into an unheated garage to acclimate it slightly
before taking it into the house. This only needs to be
done over a couple of days, since the tree should not
be in a home environment for more than five to 10 days
total. Maintain adequate moisture in the container at
all times. Evergreens will continue to transpire moisture
through the needles throughout the winter months, so
soil moisture levels are extremely important.
Handle the tree carefully when moving it about. Most
will be heavy, so take extra precautions when lifting.
A little care and forethought will make it easier for
the tree to recover during the next growing season.
Let’s take a look at some of the trees that you might
find.
Abies concolor (Concolor fir): This is a pretty tree
with great bluish-green colored needles. As a mature
specimen, it can be quite impressive, up to about 75
feet high, and about 30 feet wide. This evergreen is
one of the few that actually grows well in partial shade;
as long as it is sited in a lower pH soil with well-drained
siting. Once established, it is fairly tolerant of drought.
It transplants easily but spider mites can be a problem
if left indoors too long, and you will need to monitor
water provision to minimize root-rot potential.
Araucaria heterophylla (Norfolk island pine): Despite
the common name, this plant is not a Pinus, and does
not tolerate our cold conditions, since it originates
from tropical Norfolk Island in the South Pacific. This
species does well between 45 F to 75 F and has a high
tolerance for heat. Cold damage is likely to happen as
soon as temperatures go below 25 F. Salt tolerance is
high, making the use of softened water generally OK for
extended periods of time.
Indoor problems occur with low humidity rates; this
tropical requires about 50 percent humidity to do its
best (most homes are at about 18 percent). In order to
promote the best growth, provide at least two hours of
direct sunlight per day, rotating the plant a quarter
turn each day for even light exposure. If light levels
are insufficient, the plant will become leggy and start
to yellow.
It is not necessary to prune Norfolk Island pines as
they develop symmetrically.
Buxus microphylla koreana or Buxus microphylla koreana
x Buxus sempervirens “Green Series” (Boxwood): Makes
a great indoor holiday plant choice. Mature height and
width will vary according to cultivar (look carefully
before purchasing). They tolerate shade well, especially
in conjunction with drier soils, and require a moderate
pH (5.5 – 7.5). Outdoors, they will grow well in soils
that are moist and also well-drained soils, provided
full sun is available.
Chamaecyparis obtusa or Chamaecyparis pisifera (false
cypress): Mature height is about 60 feet with a width
of 25 feet. Choose your cultivar carefully; there are
many smaller choices available. In an outdoor setting,
they prefer moist, well-drained soils but will tolerate
a bit of intense moisture if all other growing conditions
are optimal. Full sun to partial shade will make these
lovelies happy. The needles are beautifully soft and
lightly fragrant. Color varies with cultivar. These are
moderate- to slow-growing, and worth the wait.
Citrus (of any kind): These do not survive even the
most mild of our winters. They must have high humidity,
six to eight hours of sunlight per day, moist but very
well-drained soil, moderate fertility and constant monitoring
for pests. Expect scale, whitefly, aphids, mealybug and
spider mites. Catching them early is crucial to good
control. Also, expect some leaf pathogens to invade,
and some soil issues probably will arise. Expect the
fruit to look far from perfect. Yes, there are a lot
of issues to growing tropical food crops in our neck
of the woods, but there is nothing like the scent of
citrus blossoms in late winter.
Picea glauca `Conica' (Dwarf alberta spruce): These
max out at 4 feet to 6 feet. These are fun-sized trees
with rather scratchy needles. They prefer full sun and
moist soils with a lower pH range (3.7 – 6.5). As holiday
trees, they do very well, since they transplant easily.
Rosmarinus officinalis (Rosemary): These are deliciously
fragranced for indoor enjoyment, but unfortunately, not
hardy outdoors in areas with temps below 0 F. In our
area of the world, they are most often planted outdoors
with the intention of season-to-season replacement or
to be brought in for over-wintering. They are very tolerant
of high pH levels, and are somewhat drought-tolerant
if adequate air humidity is provided.
Rosemary needs full sun indoors to thrive. For any plant
living indoors, providing appropriate nutrition during
the growing season will help it to thrive. During the
semi-dormancy of the winter months, no fertilizer is
needed. Soil should be moist but not waterlogged.
If allowed to dehydrate, repeatedly, expect to see the
lower branches die. If over-watered regularly, branches
will yellow and then die. Needle anthracnose can develop
from watering over the foliage,, so water at the base
only. To prevent root rot, plant in a sterilized potting
medium and do not allow standing water at the base of
containers.
Spider mites also will be a problem indoors, but they
can be controlled with a bit soapy water or insecticidal
soap when spotted early.
— Lis Friemoth is a horticulture diagnostician. Contact her at (262) 745-2904, P.O. Box 58, Springfield, WI 53176, visit online at www.thegardenhoe.com or e-mail her at gardenhoe@tds.net. Listen to Liz from 9 a.m. to 10 a.m. every third Saturday on WISN AM1130 radio. |
