Growing Cuttings in a Limited Space by Ken Goebel
(printed in MBS Newsletter November 2007)
To grow one or two cuttings in a single pot, place a clear plastic bag over the pot to simulate a greenhouse environment. A small heating pad under the
pot is also beneficial. Place this under a gro-lite for 12-16 hours daily. Also mist the cuttings daily to maintain a high humidity level, and thoroughly water
the rooting soil at least once a week. The rooting soil should always be kept moist and not allowed to dry out. Covering the soil with small gravel will help
to slow down water evaporation. Stiff, insulated wire or a plastic rod can be inserted vertically in the pot to prevent the plastic bag from collapsing, as seen
in the picture. A wood stick will rot in a few weeks and is not recommended for this.
(printed in MBS Newsletter November 2007)
To grow one or two cuttings in a single pot, place a clear plastic bag over the pot to simulate a greenhouse environment. A small heating pad under the
pot is also beneficial. Place this under a gro-lite for 12-16 hours daily. Also mist the cuttings daily to maintain a high humidity level, and thoroughly water
the rooting soil at least once a week. The rooting soil should always be kept moist and not allowed to dry out. Covering the soil with small gravel will help
to slow down water evaporation. Stiff, insulated wire or a plastic rod can be inserted vertically in the pot to prevent the plastic bag from collapsing, as seen
in the picture. A wood stick will rot in a few weeks and is not recommended for this.
The azalea cutting in the foreground is 3 months old, and has grown the flower recently under these
greenhouse conditions. Another flower bud is developing, and a couple of new leaves as well. This
cutting will be ready to transplant once flowering is done.
A couple of false cypress cuttings are growing in the background. These are about 2 1/2 months
old, and starting to show new tip growth.
My rooting soil is usually a 45/45/10 mix of sphagnum peat moss/grit/loam. This is an acidic rooting
medium good for cuttings from trees that tolerate acidic soil. For trees that prefer a more neutral
soil, such as crabapple, rosemary or tamarix, cuttings are grown in a neutral pH mix of 45/45/10 pine
bark/grit/loam. The pine bark is screened to about 1/8 inch particle size to remove the big chunks.
Coarse nursery sand can be substituted for the grit. The loam is a source of nutrients for faster
growth.
Vigorous new growth is a sign that the cutting has rooted, and is ready to be transplanted. At this
time, the cutting should be slowly exposed to fertilizer and to ambient room air. This is done by
removing the bag 8 hours daily for 1 week, then 12 hours daily for another week. Fertilizer is added
at 1/4-strength initially, and 1/2-strength in two more weeks. After this gradual exposure to its new
environment, the rooted cutting can be potted in appropriate bonsai soil for the tree ( See my soil
article in the Minnesota Bonsai Society Newsletter, April 2007.) If the cutting is transplanted too
quickly out of its greenhouse environment, it will probably desiccate and die. Gently place the
cutting, still with rooting soil on the roots, into its new bonsai soil and press the soil firmly around it
with your hands. Using a chopstick to work the soil is not recommended, as this will damage the
fragile new roots, and the transplant will fail.
My first attempts at growing cuttings, without a plastic bag for the greenhouse effect, were a total
failure! The plastic bag greenhouse increased my chances of successful rooting to about 50%.
Placing a small, thermostated heating pad under the greenhouse pot, and keeping the greenhouse
temperature at 70-80 degrees Fahrenheit, has further increased my success rate to about 80%.
greenhouse conditions. Another flower bud is developing, and a couple of new leaves as well. This
cutting will be ready to transplant once flowering is done.
A couple of false cypress cuttings are growing in the background. These are about 2 1/2 months
old, and starting to show new tip growth.
My rooting soil is usually a 45/45/10 mix of sphagnum peat moss/grit/loam. This is an acidic rooting
medium good for cuttings from trees that tolerate acidic soil. For trees that prefer a more neutral
soil, such as crabapple, rosemary or tamarix, cuttings are grown in a neutral pH mix of 45/45/10 pine
bark/grit/loam. The pine bark is screened to about 1/8 inch particle size to remove the big chunks.
Coarse nursery sand can be substituted for the grit. The loam is a source of nutrients for faster
growth.
Vigorous new growth is a sign that the cutting has rooted, and is ready to be transplanted. At this
time, the cutting should be slowly exposed to fertilizer and to ambient room air. This is done by
removing the bag 8 hours daily for 1 week, then 12 hours daily for another week. Fertilizer is added
at 1/4-strength initially, and 1/2-strength in two more weeks. After this gradual exposure to its new
environment, the rooted cutting can be potted in appropriate bonsai soil for the tree ( See my soil
article in the Minnesota Bonsai Society Newsletter, April 2007.) If the cutting is transplanted too
quickly out of its greenhouse environment, it will probably desiccate and die. Gently place the
cutting, still with rooting soil on the roots, into its new bonsai soil and press the soil firmly around it
with your hands. Using a chopstick to work the soil is not recommended, as this will damage the
fragile new roots, and the transplant will fail.
My first attempts at growing cuttings, without a plastic bag for the greenhouse effect, were a total
failure! The plastic bag greenhouse increased my chances of successful rooting to about 50%.
Placing a small, thermostated heating pad under the greenhouse pot, and keeping the greenhouse
temperature at 70-80 degrees Fahrenheit, has further increased my success rate to about 80%.
Shown here is a picture of one of my rooted cuttings repotted into tropical soil. This is a
'too little' ficus benjamina. The cutting came from pruning scrap that I scavenged from a
recent MBS Basics class. The Basics classes are a good source of free cuttings from a
variety of trees. This ficus cutting was placed in a plastic bag greenhouse on a heating
pad, and after 3 months had shown virtually no change in leaf structure, or any sign of new
growth. So it was gently pulled from the (acidic) rooting medium, and to my surprise had a
bunch of new roots on it. After repotting it has grown many new leaves and a few small
branches, and still growing (lighter green leaves). The tree is now about 5 months old
since transplanting, and is being trained in a mame style. Several more of these MBS ficus
cuttings that I acquired have also rooted, and have been repotted into a ficus forest.
Depending on the type of tree, a cutting grown as described here can take a few weeks to
a few months to show new growth (buds, leaves, stems, flowers), indicating successful
rooting. The ficus is quite easy to root in a few weeks. Some cuttings look like they're
doing nothing, and these can be gently pulled in 6-8 weeks to see what is happening. If
well-rooted they can be transplanted. If only a few or no roots they can be replaced in the
rooting soil and greenhouse for a few more weeks. If the cutting leaves develop a very
pale yellow color, or turn brown and shrivel up, this is a strong indication that rooting has
failed.
Patience and persistence in growing cuttings are a prerequisite for success. If you fail, try
again. Even cuttings from the same tree will behave differently, some rooting quickly, some
slowly, some not at all. This small plastic bag greenhouse technique is well-suited to small
spaces such as in apartments and condos. And it is relatively inexpensive compared to
bigger, outdoor greenhouses.
'too little' ficus benjamina. The cutting came from pruning scrap that I scavenged from a
recent MBS Basics class. The Basics classes are a good source of free cuttings from a
variety of trees. This ficus cutting was placed in a plastic bag greenhouse on a heating
pad, and after 3 months had shown virtually no change in leaf structure, or any sign of new
growth. So it was gently pulled from the (acidic) rooting medium, and to my surprise had a
bunch of new roots on it. After repotting it has grown many new leaves and a few small
branches, and still growing (lighter green leaves). The tree is now about 5 months old
since transplanting, and is being trained in a mame style. Several more of these MBS ficus
cuttings that I acquired have also rooted, and have been repotted into a ficus forest.
Depending on the type of tree, a cutting grown as described here can take a few weeks to
a few months to show new growth (buds, leaves, stems, flowers), indicating successful
rooting. The ficus is quite easy to root in a few weeks. Some cuttings look like they're
doing nothing, and these can be gently pulled in 6-8 weeks to see what is happening. If
well-rooted they can be transplanted. If only a few or no roots they can be replaced in the
rooting soil and greenhouse for a few more weeks. If the cutting leaves develop a very
pale yellow color, or turn brown and shrivel up, this is a strong indication that rooting has
failed.
Patience and persistence in growing cuttings are a prerequisite for success. If you fail, try
again. Even cuttings from the same tree will behave differently, some rooting quickly, some
slowly, some not at all. This small plastic bag greenhouse technique is well-suited to small
spaces such as in apartments and condos. And it is relatively inexpensive compared to
bigger, outdoor greenhouses.
