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(របៀបផ្សាំដើមពាំងបាយជូរជាភាសាអង់គ្លេស)
The following information was
written by Lon J. Rombough, B.S., M.S., ATM. and is used with his
permission. Mr. Rombough has an extraordinary amount of knowledge regarding
the growing of grapes and has written a tremendous book on the subject
entitled The Grape Grower. I highly recommend this
book to anyone interested in the subject. Whether a novice or an
experienced grower, this book has information for everyone. The Grape Grower can be purchased at
Amazon.com.
Growing Grapes From Cuttings
Grapes are very easy to grow from cuttings. With proper care, a
dormant cutting can be started in the spring and by fall will give a vine
large enough to bear a cluster or two of fruit the next season. The
important factors are proper care and preparation of the cuttings.
Grapes can be grown from two types of cuttings, dormant or hardwood,
and green cuttings. Dormant cuttings are the easiest to handle, but green
cuttings work in situations when it isn't possible to use hardwood, such as
for grapes that don't root easily from dormant cuttings, or when green
cuttings are all that are available.
Dormant Cuttings
Dormant cuttings can be taken any time after the vine has lost it's
leaves until the buds begin to swell in the spring. Cuttings are made from
the new shoots (canes) that grew the growing season that just ended. The
best wood is the first one to two feet of the base of the shoot where the
buds are closest together, but any healthy, well matured section of the
cane will suffice. Ideal thickness is pencil diameter up to about 3/4 inch
thick.
Thicker cuttings can be hard to handle and thinner wood may not be
mature, though thinner wood may be acceptable if the variety has naturally
small shoots. Avoid wood that is soft and spongy and has a large pith. Best
wood is dense and light green inside with relatively small pith. (See Fig.
2) Cuttings should be 12 to 18 inches long, with the bottom cut off
straight, right below the bud, and the top cut diagonally,
at least 1/2 inch above the bud to make it easy to identify the top,
insuring that the cutting will be planted right side up (See Fig.
1).
Fig. 1.
A. Best dormant cutting, from base
of cane, having 4 or more nodes (area where the bud is located).
B. Good cutting, having at least 3 nodes. C. Fair
cutting, having only 2 nodes, though suitable if cutting is otherwise
healthy.
Some growers make the diagonal
cut on the bottom. Either way works. There should be at least 3 buds
(nodes) on the cutting, more if possible, though two bud cuttings may serve
in an emergency (see fig 2).
Fig. 2.
A. Cross-section of poor cutting showing large,
spongy pith, flattened cane, and poorly matured, yellowish wood.
B. Cross-section of good, well-matured
cutting showing small, tight pith in center, round cross-section and dense,
light green wood.
Rooting occurs best at the nodes, hence the advantage in having
several nodes per cutting.
If you take your own cuttings, choose clean, healthy wood with no
discolorations from fungus or other disease, though fungus disease (black
rot, downy and powdery mildew, and anthracnose) will not harm the cuttings
if the wood well matured. Disinfect such cuttings with a 5% chlorine bleach
solution before growing them, to keep disease from spreading into the
Nursery. Try to observe the vine in bearing to be sure it is healthy - some
virus diseases can reduce crop, allowing the vine to grow more, so it looks
big and vigorous when dormant, but is unfruitful. Vines grown from cuttings
of a virus-infected vine will also have the virus. If possible, take
cuttings after there has been enough cold weather to kill any poorly
ripened wood, to insure getting mature wood. Bundle the cuttings with
plastic twine or insulated wire that won't rot or corrode and mark them
with plastic or other rot-resistant material. Use metal or plastic tags
with embossed letters or permanent ink that won't wash off in moist
conditions.
Storing Cuttings
When making your own cuttings, wrap them in moist paper or pack them
in material such as damp peat, in a plastic bag.
Keep cuttings refrigerated or store them in an unheated building, in
the crawl space under the house. Avoid places where they will freeze.
Freezing, per se will not harm them, but can take water out and dessicate
them. The ideal temperature is 32-33o F (0-1oC). Properly stored, cuttings
can be held for as much as a year or more.
Large quantities of cuttings can also be stored by burying them in
pits of sand (to prevent waterlogging) on the north side of a building.
They are buried upside down with 6 -18 inches of sand over them, covered
with tarps and boards. As spring arrives, some or most of the sand is
removed so the bottoms of the cuttings warm and callus in preparation for
planting (see callusing).
Callusing
Callus is the white tissue that forms on cut surfaces of the
cutting, and can also appear in lines along the sides of the cutting. It is
from callus that roots form. (See Fig 3 & 4)
Fig. 3.
A. Callus formation at bottom end of
cutting, near the bud.
B. Same callus a day or two later when roots begin
to show.
Callus may not always be obvious, but it must be there before roots
develop. Once roots start, they grow in cooler conditions than are needed
for callus to form. A grape cutting pushed into soil will just sit until
the soil is warm enough for callus to form, so it usually only grows a few
inches the first year. But by pre-callusing the cuttings before planting,
they can grow much more than they would otherwise, often enough to
establish the trunk of the vine, if not more.
A callused cutting planted in it's permanent location, kept weeded,
watered, and well fertilized, can establish it's roots in place as it grows
a top and can often grow enough to allow it to bear a cluster or two the
next season. This has been done in commercial vineyards in Oregon.
Nursery-grown bareroot vines have to grow a year to re-establish their
roots, before being trained up the second year, and can finally start to
bear the third year, a full year after a cutting planted at the same time.
Before callusing, be sure cuttings haven't dried in storage.
Standing them in an inch or two of water overnight will let them
"refill," improving rooting.
There are several methods to callus cuttings, according to your
situation. While rooting hormone isn't absolutely necessary, it can hasten
callusing and increase the number of roots. A very good product for the
purpose is Dip 'N' Grow (see sources) used at medium strength.
Method 1. Small amounts of cuttings can be callused by wrapping them in moist
paper or sphagnum in a black plastic bag. This is the way your cuttings
arrive, so if they have been stored properly, they are ready to callus. Put
them in a warm area that stays constantly at 80-85oF. The top of a
refrigerator is a good place as the waste heat from the condenser collects
there. Callusing should occur in one to two weeks. Buds may push and
produce white sprouts, but this isn't harmful, though care should be taken
to avoid breakage as the cutting must use energy to grow more shoots. Plant
as soon as the cuttings are callused and roots start to appear.
Method 2. Plant the cuttings in a pot of a mix of 3 parts perlite to 1 part
peat, by volume. Set the pot on a heat mat set to 85oF (25oC), in a cool
area, or even outdoors in a protected area. This heats the root zone and
encourages callusing, but the top of the cuttings, being in cool air, will
not push buds as readily. The idea is to get roots before buds push too
much so there is an existing root system to support the new growth when it
appears. Rooting occurs in one to two weeks in most cases. See sources for
a company that sells heat mats.
Method 3. Plant the cuttings in a one gallon black pot of the 3:1 perlite-peat
mix and set it in a sunny location where the pot can be warmed by the sun.
The pot should be no larger than one gallon as the warming effect of the
sun will penetrate a larger pot too slowly. Avoid excess watering as that
will cool the mix and slow rooting. This is a slower method, often taking
as much as a month, and the buds will often start to grow before the roots
are formed, but it works well enough for home use.
Larger quantities of cuttings can be bundled in lots of 50 - 100 and
rooted in the 3:1 perlite peat mix in benches with bottom heat (heat cables
or hot water pipes) set at 80 - 85oF (25oC) in the root zone. Ideally, beds
should be outdoors or in an unheated, or even refrigerated, room to retard
sprouting of the buds while the cuttings callus and root, as in method #2.
This reduces the likelihood of shoots that can break off during planting.
Planting Cuttings
Cuttings callus and root in a short time, so don't start callusing
until the planting site is ready so the cuttings can be planted
immediately. Once cuttings have a ring of callus on the base, or roots are
starting to appear, it's time to plant them.
Cuttings may be planted: 1. directly in the spot where you plan to
grow the vine; 2. in a Nursery row where you can grow them until fall, then
transplant the vine when it is dormant; 3. in a pot. In the last case, you
can start cuttings early in the year, then transplant them into their
permanent location from the pot as spring advances, or even grow them in
the pot all summer and set them out in the fall, if fall planting is
possible in your area.
If you lack means to keep the young vines watered in the permanent
location, it is better to grow vines in a Nursery or pot and transplant
them as dormant vines, which are able to take more stress when they are
planted in the permanent location.
Plant cuttings with half or more of their length in the soil to help
protect them from dessication. In very hot, dry areas the cuttings can be
covered with a mound of loose soil at first. Keep the soil loose and watch
for buds breaking through. When buds start to grow, pull the soil mound
away from them.
If some of the roots or shoots break during planting, it isn't a
disaster, but avoid it if possible as the cutting must expend energy to
grow more. If white shoots die or rot back a bit, new shoots will start
from the base of the old shoot.
Water an inch or more a week until the shoots get to six inches
long, then start using a weekly feeding of a balanced organic fertilizer,
such as fish (mixed according to directions) or a liquid chemical
fertilizer such as 16-16-16. Before the shoots are about 6 inches long, the
roots are not developed well enough to get full benefit from fertilizer. If
you use drip irrigation, the fertilizer can be applied in the water. Stop
fertilizing by mid summer and reduce or stop water soon after that to allow
the vine to harden before frost.
I have used mycorrhizal fungi with my grapes and find that these
types of fungi, which associate with the roots and help the plant take up
nutrients, are a definite benefit to the plants. They can be applied
directly to the roots or watered in after planting. Applying them to the
roots before planting seems to have the most effect. If you do use
the fungi, stay with a strictly organic fertilizer as chemical
types will inhibit or destroy the fungi. See sources for more information.
Green (softwood) Cuttings
Green cuttings are used mainly with grapes that do not root from
dormant cuttings, such as varieties derived from Vitis lincecumii or V.
aestivalis (such as "Norton"), or Muscadine grapes (Muscadinia
rotundifolia), or when dormant cuttings are not available. Muscadine grapes
started from green cuttings have a success rate of 70 to 80% versus 1 to 2
% from dormant cuttings. Green cuttings can also be used to multiply a
variety quickly, as noted farther on.
Make green cuttings from any vigorously growing shoot. Avoid shoots
that have stopped growing and are starting to harden off and turn brown.
Take cuttings as early as possible in the spring to give the young vine
extra time to harden off, unless you can keep the vine in a greenhouse.
Cuttings should be 4 to 6 inches (10 to 15 cm) long, with two or three
leaves. Remove all but the top leaf and cut that one in half if it is full
size, but leave it alone if it is a young, undersized leaf (See Fig. 5).
Cuttings with no leaves at all very seldom root.
Fig. 5.
A. Green cutting having three nodes,
with small leaf left intact.
B. Green cutting with large leaf cut in half to reduce
transpiration (water loss) from leaf surface.
Dip the green cutting in rooting hormone (see sources) and plant in
the same 3:1 perlite peat mix used for dormant cuttings. The ideal place to
plant is in mist bench with a heat cable in the bottom of it to hold
temperatures at 85oF (25oC) in the root zone. Done this way, the cuttings
will usually root in 6-9 days and be ready to pot up. Keep them under mist
or in high humidity for a few days until the new roots can keep the plant
from wilting.
When held in a greenhouse and forced with extra fertilizer, the new
vine can itself provide material for more cuttings within two or three
weeks. With this system of using each new batch of rooted plants as sources
of more material, a few cuttings can become thousands in six weeks.
A simpler alternative is to use a one gallon black plastic pot, with
a clear plastic bag over it, supported by wires (see Fig. 6).
Fig. 6. Black plastic one gallon pot with
plastic bag supported by wires, held on with rubber band, to form a humid
chamber where green cuttings can be rooted.
This creates a humid chamber that keeps the cuttings from wilting
until they root. If the pot is warmed by sunlight, rooting is slower since
the pot cools at night and may take three weeks to a month. If the pot is
sent on a heat mat, to keep the heat constant, rooting is faster.
Vines started from green cuttings need more protection when set in
the vineyard and should be surrounded by a bottomless milk carton or other
device to shade it until it can withstand direct sunlight.
Either way you do it, your new grapes will give you pleasure for as
many years as you want.
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