- Taking Pear Cuttings – How To Propagate Pear Trees From Cuttings
- How to Propagate Pear Trees from Cuttings
- Taking Pear Cuttings
- Pear Propagation
- How to Clone Fruit Trees
- Stone Fruit Propagation by Cuttings
- How to Root a Cutting from a Pear Tree
Taking Pear Cuttings – How To Propagate Pear Trees From Cuttings
I don’t have a pear tree, but I’ve been eyeing my neighbor’s fruit laden beauty for a few years. She is kind enough to give me a few pears each year but it’s never enough! This got me to thinking, maybe I could ask her for a pear tree cutting. If you’re new to pear tree propagation, like me, then a little education about how to propagate pear trees from cuttings is in order.
How to Propagate Pear Trees from Cuttings
Pear trees are native to temperate regions of Europe and hardy to USDA zones 4-9. They thrive in full sun and mildly acidic soil with a pH of between 6.0 and 6.5. They have a relatively contained height and are, thus, excellent additions to most home gardens.
Most pear tree propagation is done through rootstock grafting, but with the proper care, growing pear trees from a cutting is possible. That said, I think it is advisable to start multiple cuttings to ensure that at least one will live.
Taking Pear Cuttings
When taking pear cuttings, only take from a healthy tree. Ask permission first, of course, if you are using someone else’s tree (Suzanne, if you see this, may I have a few cuttings from your pear tree?). Select a new wood (green stem) cutting from a branch tip that is ¼- to ½-inch in width with plenty of growth nodes along the stem. Take 4- to 8-inch cuttings from dwarf fruit trees and 10- to 15-inch pear tree cuttings from those that are large. Make a clean cut at a 45-degree angle ¼ inch below a leaf node.
Pour equal part of vermiculite and perlite into a planter and water. Allow any excess to drain before planting the pear cuttings. Don’t make it soupy, just damp.
Make a hole for the cutting. Remove the bottom 1/3 bark from the cutting and place it in water for five minutes. Then, dip the end of the pear tree cutting into 0.2 percent IBA rooting hormone, gently tapping off any excess.
Gently place the bark less, hormone powdered end of the cutting into the prepared hole and firm the soil around it. Allow some space between multiple cuttings. Cover the cuttings with a plastic bag, secured at the top to create a mini greenhouse. Place the pot on a heating mat set at 75 degrees F. (21 C.), if possible, or at least in a consistently warm area with no drafts. Keep the cuttings out of direct sunlight.
Keep the growing pear trees from cuttings moist, but not wet, which will rot them. Wait patiently for a month or so, at which time you can remove the pot from the mat and place it outside in a protected area, out of direct sun, cold and wind.
Allow the trees to continue to gain in size so they are large enough to handle the elements before transplanting them into the garden – about three months. After three months, you can transplant directly into the garden. Now you just need to patiently wait for two to four years to taste the fruits of your labor.
Pear cultivars and rootstocks do not maintain their specific characteristics when grown from seed (sexual propagation). As a result seedlings are not used to propagate cultivars, instead they are used commercially for rootstock production.
Seedlings do not produce identical replicates of maternal or paternal parents. Each seedling is unique. Nonetheless, seedling rootstock production is quite practical: it is quick, inexpensive, easy to perform and produces a large number of plants. Another benefit is that the trees produced have rooting systems that grow downward and are symmetrical. To produce a seedling, seeds are removed from mature fruit of the desired rootstock, stratified and planted.
Vegetative propagation with hardwood cuttings and micropropagation is used to produce cultivars and some rootstocks. The benefit of propagation with hardwood cuttings and micropropagation is that they are clonal replicates of the parent tree and the end result is predictable, whereas the seedlings do not produce identical replicates of either parent.
The success rate of hard- and soft-wood cuttings varies between 30 to 90% depending on environmental conditions and cultivar. Hardwood cuttings are typically collected from the current year’s shoots during the fall and immersed in auxin (either higher levels for a brief dip or lower levels for an entire day). Softwood cuttings are harvested during early summer, immersed in high levels of auxin, and placed in a greenhouse with occasional misting to be hardened and ready for the nursery by fall. Both hard- and soft- wood cuttings require a humid storage environment for root formation. If the shoots are harvested early, they typically grow in the nursery for one year before reaching an adequate size for transplantation.
Micropropagation produces a clonal replicate of a tree using tissue culture. Micropropagation is a very effective and quick propagation method, but is not currently used in pear production due to the high labor and equipment costs. This method has been used by researchers, and it is expected to become common commercial practice in the future.
Micropropagation utilizes seedling tops, young shoots or suckers collected from a mature pear tree. The plant material, always containing an axillary bud, is sterilized and placed on a mixture of nutrient enriched sugar agar and plant hormones. This mixture receives long-day length lighting to produce new shoots. After the new shoots are rooted with high concentrations of IBA, they are exposed to a couple days of darkness followed by short-day length lighting to allow for proper growth. Shoots can be grown continuously and sliced to produce multiple clones of the same pear tree (Reil et al. 2007).
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If you enjoy the fruit that you harvest from your orange, avocado and apple trees, you can make more trees just like them by either planting in your own yard or giving the fruit as gifts for other to plant. And it won’t cost you anything more that a roll of grafting tape.
Germinate seeds from your apples and oranges, and sprout the pit from your avocado. The seedlings that emerge will form the rootstocks, or bottom portion, of your new trees.
Shoot pieces from the variety you wish to duplicate or clone will be grafted onto these seedling rootstocks. Fruit trees invariably consist of a rootstock, which is grown from a seed, and a scion, which is the top portion of the tree that originates in a shoot or bud from a mature, fruiting tree.
Ted Brogin, who lives in Sherman Oaks, recently reminded me of the “V” or “double V” grafting technique, also known as cleft grafting. With this technique, you remove a 3-inch to 4-inch shoot tip from your mature, fruiting tree. Then, with a well-sharpened knife, you whittle the end of your shoot tip into a V-shaped, tapered wedge. After cutting your seedling rootstock, you make a horizontal pruning cut in the flat stem surface created by the cut and insert your shoot tip into it. Then you wrap your graft with special tape.
By doing a YouTube search under either “V graft” or “cleft grafting,” you will find videos that provide excellent guidance on how to perform this simple graft. There is a particularly useful YouTube cleft grafting video done at Fairchild Tropical Botanic Garden, in Coral Gables, Fla.
In sealing your cleft graft, you will need special waxed tape known as Parafilm. On Amazon.com, I found a 90-foot roll of Parafilm grafting tape for $5.40 (this tape usually costs around $10).
You can use any well-sharpened, smooth blade whittler or pocket knife for the job, but grafting knives make the job easier and are available for about $25.
“I have taken a special liking to grafting which, to me, is taking advantage of the maturity of one tree and sharing it with a less mature tree,” Brogin said. “More specifically, I try to start rootstocks from seeds/pits and, after two years, graft on a scion from a healthy fruit-bearing tree. That approach reduces fruit bearing age of the new tree from about 10 years, if it was grown from seed, down to about three years. This is exactly what commercial growing grounds do to get trees ready for retail sellers.”
Brogin said grafting works best in shaded areas with grafts 100 percent covered with grafting tape to prevent drying out. If grating in the sun, he suggested placing a small brown lunch bag, with the corners cut off so you can see inside, over the graft to provide shade.
“If the graft is successful, new growth will break through the tape, which you will see when peeking through the bag,” he said.
After some success, Brogin encourages people to seek out other trees to graft.
“If I spot a tree that I would like to propagate, I approach the tree owner and explain my intent. I offer in exchange to graft an additional variety onto the owner’s tree or provide a newly grafted tree of the same variety,” he said. “I have never had someone say no. Other than the cost of my original fruit that I buy from the market, the cost of my fruit trees is almost nothing.”
Even if you have no fruit trees, you can start an orchard in this manner.
For instance, if your neighbor has a Hass avocado tree that you would like to clone you can buy an avocado and germinate its seed, either in a jar of water, suspending the seed over the top of the jar with toothpicks, or in a flower pot or other container.
After your seedling has developed into a little tree, you ask your neighbor for a small piece of a shoot, graft it onto your seedling and, voila! You have your very own Hass avocado tree, ready to give fruit in a few years time.
“I’ve been a renter in Downey since 1992 and I’m fortunate to have a sapote tree in the back yard — wonderful fruit and a bountiful tree. I eat some every day during harvest season, which lasts from fall through winter,” said Gary E. Myers. “I also have a large avocado tree from which I am currently harvesting the biggest and best avocados I’ve ever had. And there is a tangerine tree which is having its best year e ver.”
White sapote (Casimiroa edulis) will grow wherever orange trees feel at home. The fruit, which is in the same botanical family (Rutaceae) as all citrus fruits, is a prolific bearer, producing up to a ton of fruit per year when it is fully mature.
It has the potential to reach 50 feet in height and tolerate wetter soil than most fruit trees and will produce in less than full sun exposures. Although indigenous to the tropics, white sapote is native to high elevations and can withstand a light frost.
Much experimentation has been done with white sapote but the unpredictability of fruit quality has kept it from being more widely grown on a commercial scale.
Be aware that skins and seeds of sapote fruit are toxic. When picking a fruit, make sure a small piece of stem remains attached to it. You will know fruit is ripe and ready to eat when the stem falls off.
I, too, have noticed larger than average fruit crops on a variety of trees. My intrigue is due to the fact that this was a dry winter, rainfall being less than half Los Angeles’ average annual amount. I would not go so far as to say dry winters stimulate fruit growth, but it would appear that dry winters do not, in any event, negatively affect fruit production.
Send email to Joshua Siskin at [email protected]
How to Clone Fruit Trees
Cloning a fruit tree simply means making an exact copy. Exact copies can’t be grown from seeds due to the fact that seeds mix genetic material from two different trees. The only way to make an exact clone of a fruit tree is by taking a cutting and grafting that cutting onto a root stock. A cloned fruit tree will produce the exact same size fruit with the exact same taste as the parent tree from which the cutting was taken, above the point at which the graft was made.
Cut the tip of a branch of a good fruit tree, one that produces excellent fruit. This is the tree you will be cloning. The tip should be new growth (this season’s) and should be approximately 4 to 6 inches long and about the same diameter as the trunk of the root stock you will be grafting it to. Remove any leaves within the first 2 inches of the cut end.
Select a root stock to graft your cutting (scion) into. The root stock should be from the same tree species (graft apple to apple roots, oranges to orange tree roots, etc.). The root stock will most likely be grown from a seed. Plant your root stock where you wish your tree to grow or you can perform the graft while the root stock is growing in a container.
Make a sloping diagonal cut in the scion at the cut end. This cut will make the scion come to a somewhat sharp point. The cut should be approximately 2 inches long.
Make a similar diagonal cut in the root stock just below the first leaf or branch. Again, make the diagonal cut about 2 inches long. This will entail, in effect, cutting off the top of the root stock. The two diagonal cuts should fit together so that the scion will appear to be an extension of the root stock from the spot where you made the cut.
Fit the diagonal cut on the scion to the diagonal cut on the root stock. The cambial wood (the wood just below the bark) of the scion needs to be in direct contact with the cambial wood of the root stock. If the two pieces don’t align perfectly, match the two cambial sections along one side.
Wrap grafting tape (available at any nursery) around the two pieces, starting on the root stock and winding your way up. The tape should hold the two pieces together firmly.
Cover the wrapping and a bit of the root stock and the scion with grafting compound. This is a sticky liquid that can be applied with your fingertip. Cover the area to keep it from drying out.
Keep the soil moist and allow your tree to get plenty of sun during the day. Once new leaves begin to grow from the scion, remove the grafting compound and the tape.
Creating raised bed vegetable gardens is an incredibly simple, effective way to grow food for your family, and planting perennial vegetables and fruits will ensure that your land will keep producing food for many years to come. If you’ve already planted your vegetables and are ready to take the next step and start cultivating your own fruit supply, propagating fruit trees from branch cuttings costs next to nothing, and can quickly create a veritable forest of food. Read on to learn more about this simple, affordable way to grow your own fruit trees and berry bushes.
Fruit trees cost anywhere from $20 to $100, which can be cost-prohibitive for some, especially if you’re looking to establish a neighborhood-scale orchard. Some people attempt to grow their own from the seed of fruit purchased in a grocery store, only to find out that most fruit trees do not ‘grow true’ from seed. In other words, the fruit produced by a tree grown from seed rarely resembles the fruit that it came from and is typically a half-wild, inedible version of the fruit we are used to eating.
This is because virtually all modern fruit tree varieties are propagated clonally and haven’t been grown from seed for hundreds, if not thousands, of years. Thus, they have to be propagated by cuttings of wood from a tree of the desired variety. To make things even more complicated, most fruit trees cuttings then have to be grafted onto a special rootstock, which must be propagated separately.
Grafting is a slightly complex horticultural feat, but fortunately, there is an easier way, though it only works with certain fruiting plants. Those on the list below do not require grafting; instead, the cuttings can be rooted directly, making it much faster and easier to get your food forest growing.
Here are the basic steps:
1) Take a 6- to 8-inch cutting of a healthy, supple branch from a tree with good quality fruit, making sure it includes at least two nodes (the enlarged bumps where the leaves emerge from the stem). The cutting should be about 1/4- to 3/8-inches in diameter.
2) Stick the lower half of the cutting into a rooting medium, making sure there is at least one node above ground and one below. If you do this during the dormant season, ideally in late winter, you can use potting soil or just loose garden soil to stick the cuttings in. If you do it during the growing season, it is much more effective to root them in perlite, in which case there are two extra steps:
- Remove all of the leaves except the top two and cut these in half to minimize the moisture lost through evapotranspiration from the leaf surface during the time period that roots are forming
- Keep the cutting warm and moist. One simple method is to secure a plastic bag over the pot with a rubber band as a mini-greenhouse and use a spritzer bottle to keep it humid inside.
3) Once the cuttings begin to grow from the top, it is a sign that a substantial root system has developed below and it is safe to transplant the rooted cutting.
That’s the gist of it, but additional tips are included for each species listed below.
These are evergreen trees and cannot be propagated with the dormant season method. Take cuttings in spring using the mini-greenhouse technique instead. Olives grow quickly to 30 feet or more, though they are restricted to regions where winter temperatures stay above 20 degrees.
Related: America’s First Food Forest – From Ground Level to Canopy, Urban Agriculture is Growing Seattle
If you propagate them in late winter, figs are one of the easiest fruit trees to grow from cuttings. You can actually use much larger cuttings than the method above recommends—up to an inch in diameter and three feet long is fine—and stick them in the ground in their permanent location. Figs are slightly more cold tolerant than olives (15 degrees) and are one of the fastest trees to bear fruit from a cutting. They can be maintained as a 6-foot bush, allowing them to be grown in containers and brought indoors for winter in cold climates, or allowed to grow up to 20-30 feet tall.
Pomegranates grow into beautiful 12-foot deciduous shrubs with huge red flowers in spring, which are very popular among hummingbirds. They are slightly more cold-hardy than figs, surviving temperatures as low as 10 degrees. Propagate with either of the methods listed above and look for one of the dwarf varieties to take cuttings from if you want to grow it in a pot.
Related: 6 Surprising Fruits You Can Grow Organically Indoors in Containers!
Mulberries aren’t typically found in grocery stores, because the fruit doesn’t keep well off the tree and is not able to be shipped. That said, eaten straight from the tree, they are as enjoyable as any other berry—sweet and flavorful, with a unique, chewy texture. Late winter is the best time to propagate them, just before they emerge from dormancy. Unlike figs, olives, and pomegranates, these trees survive winters in northern climates without batting an eye. Mulberries range from large shrubs to 40-foot trees, depending on the variety.
Grapevines live for a hundred years or more and require a very substantial structure to grow on, as they develop trunks like trees and weigh hundreds of pounds when laden with fruit. They tolerate subzero temperatures and are a breeze to propagate with cuttings.
Related: For Perennial Fruit Gardens, Berries are the Way to Grow
Blueberries range from 4 to 12 feet tall, depending on the variety, and grow marvelously from cuttings. It is important to know that they need very acidic soil compared to most plants. In places where the soil is not naturally acidic, you can make it so, by mixing a hefty quantity of peat moss or decomposed pine needles (the more eco-friendly option) into the soil at planting time and keeping them mulched with the same material as they grow. Several different varieties of blueberries should be planted together, as they require cross-pollination.
These guys grow like a cross between a shrub and a short vine and usually need some type of trellis to hold them up. They can be propagated by cuttings, but there is an even easier way. A mature patch of berries develops lots of little sprouts as it expands outward from the original planting. These can be severed from the “mother” plant quite easily by slicing vertically into the ground to the cut the root that attaches them and lifting out the little sprout with its own set of roots intact. Plant it immediately in its permanent location and you will have fresh fruit within a year.
Success rates with cuttings usually range from between 25 and 75 percent, so always take more than you need. It’s nearly as easy to take 10 cuttings as it is to take 2, so you may as well propagate extra and share them with the neighborhood.
Stone Fruit Propagation by Cuttings
Overview | Propagation by: Seed | Cuttings | Grafting & Budding | References
Direct stick cutting propagation is common for several clonally propagated rootstock varieties that do not produce “true-to-type” seed (Hartmann, Kester, Davies, & Geneve, 2002). Cuttings are typically taken from the previous season’s lignified growth, although two year old growth can be used for plum rootstock varieties in the late fall or winter. Plum is the easiest stone fruit to root by cutting.
Hardwood cuttings should be collected from healthy exterior shoots growing in full sunlight, with normally spaced internodes. Cuttings should not be collected from overly vigorous or weak shoots. Basal or central stem portions of last season’s growth have the best rooting ability. Leaves attached to cutting wood should be removed prior to storing or sticking and the stem terminus should be removed prior to rooting. Although rooting percentage is increased when cuttings are collected from October to January (Loreti & Morini, 2008), the ideal time frame for collecting cuttings varies among varieties.
Hardwood cuttings 10 to 12 inches in length are needed for rootstocks to enable scion bud insertion (Loreti & Morini, 2008). Rootstock cuttings should be ¼ inch to 1 inch in diameter, depending on the method of budding used (Hartmann, Kester, Davies, & Geneve, 2002). The bottom cut should be made directly below a node while the apical cut should be made ½ inch to 1 inch above the uppermost node. Disbudding, removal of lower axillary buds prior to sticking, will reduce suckering. However, do not remove all buds on the cutting because new leaf growth in the spring is needed to provide photosynthates to the growing bud and new root system. If prepared cuttings will not be used immediately after collection they should be bundled, make basal and apical cuts with a band saw, and dip tips in wax to prevent drying and indicate terminal orientation. Cuttings should then be stored in moist (not soaking) peat moss, newspaper or sawdust, placed in polyethylene bags, and refrigerated at 32-40°F (Westwood, 1993, p. 120; Hartmann, Kester, Davies, & Geneve, 2011, p. 350).
Check cuttings frequently to make sure buds remain dormant. In some varieties that are difficult to root it may be necessary to use rooting hormones, callus formation, or root initiation prior to cold storage. Soak basal cuts in IBA at 10-25ppm for 12-24 hours, or quick dipped in1000-5000ppm IBA for 5 seconds in IBA (Westwood, 1993, p. 117; Loreti & Morini, 2008, p. 226). Place the basal portion of the bundled cuttings in 3 inches of moist peat above 8 inches of sand above heating mats or circulating hot-water tubing. Maintain bottom heat at 18 to 21°C and expose the top portion to cold air to ensure bud dormancy (Hartmann, Kester, Davies, & Geneve, 2011, p. 350). Cuttings can also be spaced closely together, if bundling is not desired, in liners or beds with bottom heat similar to those used for bundle cutting wood. Field transplantation must occur before bud dormancy is broken.
Direct Spring Planting
Orchard soil should be prepared and fumigated prior to planting. Rooted liners should be planted at high density spacing in prepared beds in late February to early March. Budding occurs between late May and early June.
Direct Fall (Summer) Planting
California’s mild winters permit direct planting in the fall. This form of propagation requires less labor and space because prepared rootstock cuttings are rooted directly in the field, not in liners or heated propagation beds. Cuttings should be planted in nursery rows between November and December and allowed to root over winter (LaRue, 1989). Peach, and peach x almond hybrid, rootstocks should be treated with IBA prior to sticking. Once buds from rootstock cuttings start to break dormancy prune them to allow only one bud to grow. June budding on rooted cuttings should be done in late May to early June.
Several Prunus species and cultivars are listed in the UC Davis Plant Sciences Rooting Database at http://rooting.ucdavis.edu/pchome.htm (Burger, 2009) with a brief overview of cutting type, rooting method, and percent success. Although propagation with hardwood cuttings is still used, tissue culture is becoming more popular.
All trees have a shoot system, or top, and a root system. With few exceptions, the top is genetically different from the root system. They are two different plants, genetically distinct, growing separately. The separate plants were united in a way that caused the two to grow together and function as one. This is accomplished through plant propagation.
There are two methods of plant propagation: sexual (seed) and asexual (vegetative). Sexual propagation entails the recombination of genetic material. In nature this results in progeny that differ from each other and from their parents. Vegetative propagation is clonal; progeny are genetic copies of the parent plant.
Budding and grafting are asexual or vegetative techniques used to maintain the cultivated varieties (cultivars) nearly all of which are clones. Due to open pollination, more than 99 percent of all seedlings grown from clones bear fruit that is inferior to that produced by the parent trees. Fruit will be unlike parents in flavor, color, date of ripening, and many other characteristics – typically not “true-to-type” or “true-to-name.” For this reason, it is necessary to graft or bud most kinds of fruit tree seedlings to the desired variety to obtain a “true-to-name” tree of any known variety.
Although all members of the same clone have the same genetic makeup and can be exactly alike, environmental factors can greatly modify the expression of the genetic character so that the appearance and behavior of individual plants can be strikingly different. An orchard of ‘Delicious’ apples that is pruned, irrigated, sprayed and fertilized properly for high quality productivity will appear totally different from an adjacent abandoned orchard of the same cultivar, yet the plants are genetically identical.
Cuttings are used mainly in the clonal propagation of herbaceous and some woody ornamental species. Cuttings are less frequently used for fruit and nut trees. A cutting is a piece of vegetative tissue (stem, root or leaf) that, when placed under suitable environmental conditions, will regenerate the missing parts and produce a self-sustaining plant.
Stem cuttings are of several types. Some species can be readily propagated from hardwood cuttings of stems taken in late winter or early spring. These cutting, which include several nodes (usually 6-12″ of stem), are placed in the ground in nursery rows with just the top bud showing. The cuttings will generate roots and can be, after a year’s growth, transplanted as self sustaining plants.
Grapevines can be readily rooted using hardwood cuttings and have long been propagated this way. This is one reason that some of our grape cultivars are so ancient. Some olive cultivars are also readily propagated by stem cuttings. Fig and pomegranate can be propagated this way. Most other fruit and nut tree species will not form roots from hardwood stem cuttings, or will only do so with great difficulty. Some of these can be induced to produce roots by treatment with plant hormones and/or heating the cutting beds; others cannot be induced to form roots under any circumstances.
Layering is another method of rooting stems, in which stems are induced to produce adventitious roots while they remain attached to the parent plant. Some plants (blackberries, raspberries) naturally form layers when the tips of branches touch the ground (tip layering). Others can be manipulated to do so by simple layering or mound layering.
Simple layering is used to propagate filberts (hazelnuts). In early spring a long shoot is bent to the ground, placed in a hole several inches deep, and bent back so that the tip of the shoot is exposed above ground. The hole is then filled with soil. The curved section is usually cut or nicked which promotes rooting. After one season’s growth the rooted layer is cut from the parent plant, dug and transplanted.
Mound or stool layering is widely used to produce clonal rootstocks of apple and plum. Plants are cut back almost to ground level and allowed to sprout new shoots, soil (or a mixture of soil and sawdust) is mounded up around the bases of these shoots and the mound is built up as the shoots grow. Roots develop at the bases of these shoots. The following spring the rooted layers are cut off and transplanted into nursery rows for another season’s growth. The stool bed is handled in the same way the next year for another crop of rooted layers.
Grafting & Budding
Grafting and budding are the most important means of propagating fruit and nut trees for two reasons:
- Species and cultivars that cannot be propagated by cutting or layering can be propagated by budding and grafting.
- Budding and grafting allows the use of rootstocks with desirable characteristics that make them preferable to growing a tree on its own roots.
Grafting and budding involve joining two genetically distinct plants so that they unite to continue growth as a single plant. The two parts of the compound plant are known as the stock (or understock or rootstock) and the scion. The stock refers to the lower part of the grafted plant—the part that produces the root system. The scion is the upper portion that produces the shoot system. In budding, a detached bud of the desired variety is placed under the bark of a seedling tree. In a few weeks, the bud shield and the seedling heal together, then the bud of the desired variety grows to produce the new tree, which is genetically like the parent tree from which the bud was taken and which produces fruit true to the variety.
In grafting, a short section of a shoot taken from a tree of the desired variety is inserted into a limb or trunk of a seedling tree.
There are several methods of grafting and budding; in all the objective is to bring the cambium layers of the stock and scion together and to hold them tightly while the graft union forms.
Buds on the scionwood and budwood (material to be used as the scion or bud source) must be dormant when the grafting or budding is done. For whip and cleft grafts the operation is done with freshly collected scionwood onto dormant stocks. Bark grafting is done after growth has started in the spring; for this purpose scionwood is stored at about 0°C until it is used.
It is essential, for all grafts, that the graft union be held together tightly and secured by tying or wrapping using string or rubber bands (whip graft), wedging (cleft graft), or even nailing (bark graft). The fresh graft is sealed with grafting wax to prevent drying of the graft union before it heals.
Whip graft: the stock and scion are of more-or-less equal diameters. Whip grafting is often used in root grafts where scion wood is grafted to a piece of root. Illustration of whip grafting.
Cleft graft: scionwood ¼ to ½ inch in diameter is inserted into stubs of stock that are 3 to 4 inches in diameter. Usually done in the late winter, early spring before growth resumes.
Bark graft: Used for species that are difficult to graft. Done in the spring after growth has resumed and the bark separates easily from the wood.
T-budding is the most common method for propagating fruit trees. In T-budding, a T-shaped cut is made in the stock. Buds (taken from budsticks or budwood) are inserted under the bark of small seedling stock plants a few inches above ground level. The buds are inserted and tied in place with budding rubbers. After growth starts the tops of the seedling rootstocks are cut off. T-budding is usually done in the late summer. T-budding illustrated.
Patch-budding is used for thicker barked trees, especially walnut and pecan. Here a patch of bark is removed and a same-sized patch with the bud is inserted in its place. Patch budding is normally done during the growing season when the bark separates readily from the wood along the cambial layer.
If you have one peach tree in your yard and want to extend its fruit-bearing season, you can bud or graft one or more variety of peach on it. You can bud several varieties of peach on a young tree or graft two or three additional varieties onto an older tree or add a pollinating variety to a tree by grafting.
Within a limited amount of space, you can grow several varieties of fruit on a few trees. However you can usually grow only like kinds of fruit on the same tree. There are a few exceptions to this rule. For example, you can grow plums, apricots, almonds, nectarines, and peaches on peach seedling roots, but the growth habitat of each differs, so it is difficult to manage these different species on the same tree. The safest method is to put varieties of like fruits (species) on one tree and varieties of another on a separate tree.
Rootstocks are a means to propagate clonal cultivars. Many species and cultivars cannot be propagated on their own roots. The only means of clonal propagation is by grafting or budding onto rootstocks of the same or related species. Rootstocks offer an opportunity to adapt a given tree to additional environmental factors as well, and, in many cases, trees on carefully selected rootstocks, can be grown in sites where it would otherwise be impossible or nonproductive.
Rootstocks provide resistance or protection against soil-borne organisms that are pathogens or pests. More common than insect-resistance (i.e. phylloxera) is resistance to soil-borne pathogens, especially pathogenic fungi and some bacteria. These include organisms that cause oak root rot, stem and crown rots, wilt diseases and crown gall. Another important class of soil pest is nematodes, microscopic worm-like organisms (not related to earthworms), which can be highly damaging to a great range of plant hosts. Peach trees are highly susceptible to some species of nematodes; ‘Nemagard’ rootstocks for peach are resistant and allow peach trees to grow in nematode-infested soils.
Virus-resistance is an issue for citrus. Sour orange, once widely used as a rootstock for sweet oranges, is no longer used in California because it is susceptible to tristeza virus (quick decline). Appropriate rootstocks are used for local conditions. If, for example, oak-root fungus is not a problem in an area, there is no advantage to using an oak-root fungus-resistant rootstock.
Other factors involved in the selection of rootstocks.
Controlling tree size: Ultimate tree size can be controlled by rootstock in many species. Apple is the best example. A complete series of apple rootstocks exist which regulate the size of the tree from the most dwarfing to quite large. Dwarfing rootstocks are used in many other species: pear, cherry, plum, peach, citrus and others.
Adaptation to unfavorable soil conditions: Rootstocks may be tolerant of poorly drained, heavy clay or saline soil conditions.
Resistance to low winter temperatures: Some species, especially apple and citrus, survive cold winters better on some rootstocks than others.
How to Root a Cutting from a Pear Tree
The pear is a hardwood tree and is often grown from seed. However, starting a pear tree from a cutting is not terribly difficult, although more than one attempt may be needed before you achieve success. Always take your cuttings from new growth, never old and woody growth. Also keep in mind that younger trees have a better propagation rate than older trees, so whenever possible take your cuttings from younger trees. Cuttings can be taken in late summer or early fall.
Cut the end of a branch of new growth approximately 6 inches long. Make the cut just below a leaf node as the node is the best place for roots to start. The cutting should be about the thickness of a pencil.
Remove any leaves from the lower 1/3 of the cutting.
Dip the cut end of the cutting into a rooting hormone powder, available at any nursery and most home centers. Keep as much powder on the cut end as possible.
Fill a growing pot with regular potting soil that is moist but not soaking wet. Poke a home in the soil with your finger or a pencil that is 2 to 3 inches deep. Carefully insert the cut end of the cutting into this hole and pack the soil around it.
Cut the bottom from a clear plastic 2-liter soda bottle and place the bottle over your cutting to form a small greenhouse.
Place your cutting near a window where it will receive plenty of indirect light and stay warm. Do not put your greenhouse in direct sunlight or you may bake your cutting and kill it.
Watch for new growth. New growth should appear after 3 to 4 weeks. Once new growth appears remove the plastic cover and allow your plant to receive several hours of direct sunlight each day. Keep the soil moist but not saturated. Your cutting has now rooted.
Rooting of semi-hardwood pear cuttings of Taiwan Nashi-C and Limeira rootstocks, under controlled environments either in a chamber of the B.O.D. (Biochemical Oxygen Demand) type or in a greenhouse was investigated. Semi-hardwood cuttings without leaves, 20 cm long, were treated with 0, 2000, 4000, 6000 and 8000 mg L-1 of indolebutyric acid (IBA), for 5 seconds and placed in a vermiculite and sand mixture substrate (1:1 v/v), humidified weekly with a medium containing MS saline solution and sucrose 1%. Cuttings remained 42 days in both the B.O.D. chambers (26°C, 100% of humidity and 14 hours of photoperiod) and in the greenhouse with an intermittent irrigation system. In B.O.D. chamber, cuttings without IBA showed callus formation seven days after planting. In the greenhouse, callus formation occurred only 21 days after planting. In IBA treated cuttings, callus appeared around the base of the cuttings three days after B.O.D. chamber incubation. Roots emerged from the base tissues and callus and became more evident after the 14th and 28th days, for B.O.D. chamber and greenhouse treatments, respectively. It was verified for Taiwan Nashi-C that the better rooting percentage (92.9%) and root number (7.85) were found using 6000 mg L-1 of IBA concentration in the B.O.D. chamber. Use of B.O.D. with controlled temperature, light and humidity, related to the IBA, was shown to be more advantageous for Taiwan Nashi-C and Limeira semi-hardwood cutting rooting, so favoring the vegetative propagation of pear trees.