A plastic greenhouse for only a
penny"
Sure it's low in cost, but it's high in performance, and you can build it
yourself in almost less time than it takes to read this piece. Once you do,
you'll be able to take cuttings and to propagate new plants all year round
instead of just for a few weeks in the summer. Here's how to go about it:
Materials needed include a two quart plastic freezer bag - it costs a penny! -
some peat moss and sand. The USDA recommends this common sense method, which it
has found successful with shrubs, trees and all varieties of houseplants.
The schedule for taking or making cuttings lasts all year long. Roses and spring
flowering shrubs are best done in midsummer before succulent growth hardens off.
House plants may be done at any time - depending on species and variety, while
the evergreens like holly and yew are done in the late fall and early winter.
Using a sharp knife, make the conventional slanting cut about two to six inches
below the top of the cutting. Strip off all the lower leaves and wrap the
cuttings in a damp towel to keep them fresh.
Next, fill the clean, airtight freezer bag with four inches of the rooting
mixture - two parts of peat moss to one part sand - which should be moistened.
Then insert 10 to 12 cuttings two to three inches deep, planting so closely that
their leaves barely touch. Spray lightly with water, and twist the top of the
bag closed, securing it with a rubber band.
You have now made a miniature, vapor proof "greenhouse" containing cuttings that
will need no more water until they are very well rooted indeed. Set it in a
north window where it gets plenty of daylight but never direct sunlight, which
could kill the tender young shoots. Put aluminum foil under the bag to protect
the sill from dampness.
The cuttings should be rooted by the time they have been in the window for two
months. Open the bag gently and then very carefully dig around one of them,
inspecting it for roots. If none are visible, replant the cutting, close the bag
again, and set it back in the light. Inspect again once a month during the
growing season until the cuttings are rooted or turn black, which means they
have died. Most will be rooted, and these should either be moved to a cold frame
or planted in a shady spot where alternating heat and cold do not have a chance
to kill new plants. A variation on the above greenhouse method, recommended by
the U.S. Agricultural Research Service, is to insert the cuttings into a six
inch flowerpot containing a rooting medium of one part peat and one part sand,
and enclose the whole pot in the plastic bag. Whichever method you choose,
however, is well worth the effort.
More Free Row Covers for Early Plants
You can build a free "greenhouse" for a row of plants set out in the garden
early by using old storm windows standing lengthwise. Just dig the storm windows
about eight inches into the soil on all sides of the row, seal each space where
the windows join with tape, and top the "greenhouse" with either more storm
windows or clear plastic.
A simple wooden frame built over a row of early plants and covered with clear
plastic will serve the same purpose.
Or you can make a plastic tent "greenhouse" by draping clear plastic over tall
wire wickets placed in the row, clipping the plastic to the top of each wicket
with clothespins, and holding the plastic in place at ground level by covering
it with soil.
It is important to remember that adequate ventilation must be provided with any
covering used for early plants. This is particularly important in areas where
cold or cool spring weather is occasionally broken by temperatures like those on
a hot summer day. Plants can be broiled alive under tight coverings on such
days. Either be sure to provide small openings that will let excess heat escape
on warm spring days (and can be sealed when it gets really cold), or else go out
in the garden and remove all coverings, replacing them at night. It's also a
good idea to introduce a few beneficial insects (such as ladybugs) under any
shelters you make. They will devour those harmful bugs that tend to congregate
in warm places in early spring.