|
Home
>
Virtual Greenhouse
> Indoors
Knowing When to Come in
from the Cold
by Brad Thompson
This article is about when and how to bring your
begonias back indoors for the winter. It will be in two
parts. Part one will be tips for Northern Growers who
have no choice about whether to winter their begonias
indoors. Part two will be tips for Southern Growers who
may choose to do as the Northerners do or prepare their
plants for a winter outdoors. There is no one method to
follow when growing begonias or for how you winter them
or bring them indoors. This article is to give you
information and tips so you can formulate a plan that
works for you and your growing conditions.
Part
One: Northern Growers
Northern growers have the added hardship of having a
limited growing period when their plants can grow
outdoors. You can choose to do 2 things; you can leave
your plants indoors all year or you can grow them
outdoors during the warm months and bring them in for
the cold ones.
Some of you may choose to only bring cuttings indoors
after the summer. This has a plus side and a down
side. One is you can save space by restarting new
plants each fall from cuttings but if the cuttings fail
then you have lost the variety. You can avoid some of
the risk if you plan ahead. Most of you know when the
first frost will usually come for your area. You should
start your cuttings started well in advance of that
first frost even before you have to start using the
furnace. You'll have more of a chance of success.
You'll give the newly rooted plants plenty of adjustment
time. You'll also have a chance to try again before
losing the original plant outdoors by taking more
cuttings if you have a problem.
Plants started early before the furnace starts
running full time will have time to adjust to the lower
humidity associated with forced heat. Cuttings taken
from the cold, damp fall and rushed directly into the
warm, dry indoors will be shocked for sure. Fall is a
time when generosity can help you out too. If you start
sharing cuttings with friends you can think of it as
banking your begonias. If something were to happen to
yours you'll have a source for retrieval. You might
even convert a few friends to begonias and gardening.
You don't have anything to lose. If you bring your
plants indoors, you'll probably still have to do some
trimming and if you leave the plants outside they're
going to freeze anyway.
If you decide that you really want to bring the
entire plant in instead, you still need to plan ahead.
You can't just wait till you think it's going to freeze
and then rush them indoors. They need to adjust just
the cuttings would and gradually is best.
If you plan on bringing the entire plant back in
every year, you should just plan on leaving the begonias
in pots to begin with. Pots can be set in beds with
plants around them to disguise the pots and make them
appear to be planted in the beds. Or you can arrange
the pots on shelves or a decorative display. The reason
for keeping them in the pots is that it will be less
stress on the begonia. If you plant in the ground, they
have to go through being yanked out of the ground,
having their tops trimmed and then going into a totally
new environment. The potted plants may need some
trimming back and maybe a few cuttings taken for
insurance but they can basically be inspected for pests
and then just brought back in. Whether the plants are
in pots or in the ground, you still need to bring them
in early just like with the instructions for the
cuttings.
Plants in the ground will be more work, but the
advantage is that in the ground your plant may have
grown many times faster than it would have in a pot.
The disadvantage is that you're going to have to trim
the tops back to match the size of the rootball. You
have to remember that the begonia might have had several
feet of roots supporting that big plant. You can't
expect to just dig it up with only a fraction of the
roots, stick it in a pot and not have it go into shock.
The lesser roots can't usually keep up with the water
required for all that top growth. It isn't so bad
though, you can root those extra cuttings and have
either spare plants or backup plants.
Some plants may still require some extra help to
adjust and recover. If you grow under lights you can
accomplish this by tenting your light stand to keep the
humidity in. You may want to do this even if your
plants stay in all year. It does cut down on watering,
and the plants grow more lush. Make sure to use non
flammable plastic film and make sure it isn't directly
touching the light fixture. Clear plastic will allow
you to see the plants even when covered. I also use
trays filled with large perlite or gravel to set the
pots on. This will give the water somewhere to go when
watering. It will also raise the humidity if kept moist
continuously. If you only have a few plants or don't
have a light stand, misting them frequently or placing
them in an old aquarium to keep the humidity in will
help. You can gradually remove the cover of the
aquarium to adjust them to growing outside it.
When I grew in Iowa, I had an old redwood picnic
table with two benches. In the summer the picnic table
was a picnic table but during the winter it became a
light stand. I would place it in front of an
appropriate window with one of the benches on top. This
gave me an area for growing plants in natural light. I
hung a florescent fixture under the table and enclosed
the table legs with plastic film. This gave me my
florescent light growing area. I kept everything from
geraniums to begonias through the winter under that
redwood table.
I even grew a B. 'Sophie Cecile' under there, but at
the time, being ignorant of begonias (I might still be
ignorant) I thought it was some tropical species since
it wasn't named. I was very impressed with it and at
the time had to save for awhile to buy it from a local
greenhouse. I looked at it for a month and drooled over
it before I had the $20 or whatever it cost. I had
never seen anything so exotic looking before. Even then
I tried crossing it with semps, the only other begonias
I'd seen. I wasn't successful but I remembered my
experiences a few years later when I ran into a cane
begonia again here in California. It was a B. 'Pink
Jade' at a swap meet. I couldn't pass it up since it
was $5 and bigger than that B. 'Sophie Cecile' I'd had
years before. I thought again I had really gotten a
deal. I guess I did since it led me to the Begonia
Society.
Part Two: Southern
Growers
Many Southern Growers will be following some of the
methods above, especially if they don't live in frost
free areas. Likewise, many Northern Growers with be
able to use some of the Southern tips to help them
preserve struggling plants.
Besides having a much longer growing season overall,
southern growers in some areas are even able to keep
their begonias outdoors all year round. Even in those
areas, there are some precautions and procedures that
can be taken to assure the plants will survive the
winter. In most southern areas, although it doesn't
freeze often or ever, they still have to contend with
cold, wet weather. As most of you know, cold and wet
are two conditions begonias hate with a passion.
So, what can you do about it? One procedure that I
practice in my yard, I'll call "crop rotation". As the
seasons change and the available light changes different
begonias are moved to take advantage of the best light.
In the winter, more delicate varieties are moved either
into areas that have good winter light or that are more
sheltered. Since the only way you can solve the "cold"
problem is by constructing a greenhouse most of you will
have to settle with solving the "wet" problem. Begonias
can stand cold temperature much better than they can
stand wet feet. Sensitive begonias can be moved under
awnings or porch roofs, etc. to keep them from excessive
rain. Some growers even go so far as to cover their
shade houses with plastic sheeting. That will keep all
the begonias dry. You will have to consider what your
neighbors will say when it happens that you are standing
outside watering your begonias in the pouring rain. If
you choose to totally enclose the shadehouse with
plastic, including the sides, you'll have to take into
account that there will be warm winter days. Your
winter enclosure probably won't have heat or cooling. I
would suggest leaving at least one side open or that you
can close at night or on cold days.
Many growers don't have the option of covering or
rotating because of limited space or limited time.
Those growers have no choice but to just leave the
begonias where they are. There are still things you can
do. The most important thing is correct pot size. Do
you have any plants that seem to stay wet all the time?
Those plants are either over potted or root damaged or
both. If they're staying too wet now just imagine how
wet they'll stay this winter in the rain. Now is the
time to correct the problem before it gets worse.
Gently lift the plant out of its pot. You will see that
some or most of the soil stays in the pot or falls off
the plant when you lift it out. This shows you the
plant is in too large a pot or that the roots have died
to the point that they don't hold the soil together
anymore. In the spring, when you are moving plants up
to larger sizes, it's expected that many will be growing
into those larger pots. During the winter, however,
these plants will only decline further. The solution is
to remove all the loose soil from the plant. Once the
soil is removed, find a pot that is only slightly larger
than the remaining rootball. Replant the begonia into
the new pot. Next spring you will usually find the
plant fully recovered and ready to move back up to a
larger pot again.
If you live in an area that has an occasional frost
some years, you should have precautions ready. Many
growers save old sheets to cover the plants with if a
frost is expected. Some also save large cardboard boxes
to totally enclose plants with. Plastic sheeting can be
used but if you also have rain, you can break plants.
Plus, when the sun comes out, many plants can be burned
by the heat through the plastic. A newer innovation is
a type of plastic that has microscopic holes in it so it
allows air, heat and water to pass through it but still
protects from frost. I've heard from growers that have
used it, that said they were able to keep the covering
on for a couple of weeks without the daily removal and
the plants were fine. This would be a big benefit over
the other coverings which you will have to remove during
the day and replace every night during cold spells. I
can't tell you the exact name of the plastic but it is
available from most mail order seed companies, such as
Parks Seed.
Though I haven't tried this myself, I have heard from
growers who live in areas with some frost, that trim
back their begonias and mulch heavily with straw or a
similar mulch. If you have found that you live in an
area where the frost is just enough to completely freeze
most begonias, you might try the mulching. You wouldn't
have anything to lose. When you trim back the plants,
the cuttings can be taken indoors for the winter. The
roots can remain in the ground under the mulch.
With all the different variables across the country,
I can't specifically tell anyone exactly what will work
in their area. The suggestions above are to help you
experiment in your yard to see what will be successful
for you.
|
