THE COLDFRAME AND THE HOTBED
The simplest form of home glass is the coldframe. The simplest hothouse
is the manure heated coldframe or hotbed.
The following directions for making the frames and preparing the soil
for them are taken from the author's _Home Vegetable Gardening_.
For the ordinary garden, all the plants needed may be started
successfully in hotbeds and coldframes. The person who has had no
experience with these has usually an exaggerated idea of their cost and
of the skill required to manage them. The skill is not as much a matter
of expert knowledge as of careful regular care, daily. Only a few
minutes a day, but every day. The cost need be but little, especially if
one is a bit handy with tools. The sash which serves for the cover, and
is removable, is the important part of the structure. Sash may be had,
ready glazed and painted, at from $2.50 to $3.50 each, and with care
they will last ten or even twenty years, so you can see at once that not
a very big increase in the yield of your garden will be required to pay
interest on the investment. Or you can buy the sash unglazed, at a
proportionately lower price, and put the glass in yourself, if you
prefer to spend a little more time and less money. However, if you are
not familiar with the work, and want only a few sash, I would advise
purchasing the finished article. In size they are three feet by six.
Frames upon which to put the sash covering may also be bought complete,
but here there is a chance to save money by constructing your own
frames--the materials required being 2 x 4 inch lumber for posts, and
inch-boards; or better, if you can easily procure them, plank 2 x 12
inches.
So far as these materials go the hotbed and coldframe are alike. The
difference is that while the coldframe depends for its warmth upon
catching and holding the heat of the sun's rays, the hotbed is
artificially heated by fermenting manure, or in rare instances, by hot
water or steam pipes.
In constructing the hotbed there are two methods used; either placing
the frames on top of the manure heap or by putting the manure within the
frames. The first method has the advantage of permitting the hotbed to
be made upon frozen ground, when required in the spring. The latter,
which is the better, must be built before the ground freezes, but is
more economical of manure. The manure in either case should be that of
grain-fed horses, and if a small amount of straw bedding, or leaves--not
more, however, than one-third of the latter--be mixed among it, so much
the better. Get this manure several days ahead of the time wanted for
use and prepare by stacking in a compact, tramped down heap. Turn it
over after three or four days, and re-stack, being careful to put the
manure from the top and sides of the pile now on the inside.
Having now ready the heating apparatus and the superstructure of our
miniature greenhouse, the building of it is a very simple matter. If the
ground is frozen, spread the manure in a low, flat heap nine or ten feet
on each side, a foot and a half deep, and as long as the number of sash
to be used demands. A cord of manure thus furnishes a bed for about
three sash, not counting for the ends of the string or row. This heap
should be well trodden down and upon it should be placed the box or
frame upon which the sash are to rest. In using this method it will be
more convenient to have the frame made up beforehand and ready to place
upon the manure, as shown in one of the illustrations. This should be at
least twelve inches high at the front and some half a foot higher at the
back. Fill in with at least four inches--better six--of good garden soil
containing plenty of humus so that it may allow water to soak through
readily.
The other method is to construct the frames on the ground before severe
freezing, and in this case the front should be at least twenty-four
inches high, part of which--not more than half--may be below the ground
level. The 2 x 12 inch planks, when used, are handled as follows: stakes
are driven in to support the back plank some two or three inches above
the ground,--which should, of course, be level. The front plank is sunk
two or three inches into the ground and held upright by stakes on the
outside, nailed on. Remove enough dirt from inside the frame to bank up
the planks about halfway on the outside. When this banking has frozen to
a depth of two or three inches, cover with rough manure or litter to
keep frost from striking through. The manure for heating should be
prepared as above and put in to the depth of a foot, trodden down, first
removing four to six inches of soil to be put back on top of the
manure,--a cord of the latter, in this case, serving seven sashes. The
vegetables to be grown, and the season and climate, will determine the
depth of manure required--it will be from one to two feet,--the latter
depth seldom being necessary.
It must not be overlooked that this manure, when spent for heating
purposes, is still as good as ever to enrich the garden, so that the
expense of putting it in and removing it from the frames is all that you
can fairly charge up against your experiment with hotbeds, if you are
interested to know whether they really pay.
The exposure for the hotbeds should be where the sun will strike most
directly and where they will be sheltered from the north. Put up a fence
of rough boards, five or six feet high, or place the frames south of
some building.
The coldframe is constructed practically as in the hotbed, except that
if manure is used at all it is for the purpose of enriching the soil
where lettuce, radishes, cucumbers or other crops are to be grown to
maturity in it.
All this may seem like a lot of trouble to go for such a small thing as
a packet of seed. In reality it is not nearly so much trouble as it
sounds, and then, too, this is for the first season only. You will have
a well built frame lasting for years--forever, if you want to take a
little more time and make it of concrete instead of boards.
But now that the frame is made, how to use it is the next question.
The first consideration must be the soil. It should be rich, light,
friable. There are some garden loams that will do well just as taken up,
but as a rule better results will be obtained where the soil is made up
specially, as follows: rotted sods two parts, old rotted manure one
part, and enough coarse sand added to make the mixture fine and crumbly,
so that, even when moist, it will fall apart when pressed into a ball in
the hand. Such soil is best prepared by cutting out sod, in the summer,
where the grass is green and thick, indicating a rich soil. Along old
fences or the roadside where the wash has settled will be good places to
get limited quantities. These should be cut with considerable soil and
stacked, grassy sides together, in layers in a compost pile. If the
season proves very dry, occasionally soak the heap through. In late fall
put in the cellar, or wherever solid freezing will not take place,
enough to serve for spring work under glass. The amount can readily be
calculated; soil for three sash, four inches deep, for instance, would
take eighteen feet or a pile three feet square and two feet high. The
fine manure (and sand, if necessary) may be added in the fall or when
using in the spring. Here again it may seem to the amateur that
unnecessary pains are being taken. I can but repeat what has been
suggested all through these pages, that it will require but little more
work to do the thing the best way as long as one is doing it at all, and
the results will be not only better, but practically certain--and that
is a tremendously important point about all gardening operations.
While the cold frame and hotbed offer great advantages--especially in
the way of room--over growing plants and starting seed in the house,
they are nevertheless incomparably less useful than the simplest small
greenhouse. Plants may be wintered over in them, violets may be grown in
them, lettuce may be grown late in the fall and early in the spring, and
followed by cucumbers. But they are not convenient to work in. One is
dependent on the weather. They are not satisfactorily under control.
Take, for instance, one of those dark fall days, with a cold nasty
drizzle cutting down on a slant, or one of those bright sunny and cloudy
chill-winded spring days, when no pleasure is to be had out-of-doors.
Under the shelter of your little glass roof, where you can make your own
weather, what fun it is to be potting up a batch of cuttings, or putting
in a few packets of choice seed for the extra early garden! There is
nothing like it.