Posts Tagged: grafting
UCCE advisor speaks about vegetable grafting at neighboring university
Zheng Wang, vegetable crops advisor with UC Cooperative Extension in Stanislaus County, visited an ag class at Stanislaus State to discuss a state-of-the-art vegetable production practice that involves grafting, reported Alivah Stoeckl in Stan State News.
Grafting plants onto specially bred rootstocks is a practice that is common in tree crops. Grafting confers resistance to soil-borne diseases and pests, requiring less inputs and leading to sustainable crop productivity. It is now being used in some vegetable and fruit crops, such as tomatoes, eggplant, watermelon, cucumbers and cantaloupe.
“Grafting conveys a lot of merits in terms of disease resistance and yield maintenance. It enriches the production practices by introducing more variety. And by making impossible things become possible,” Wang said.
Vegetable grafting has been used since early 2000s, but to many agriculture students the idea was new, reported Stoeckl.
“We're moving forward and advancing with our food which I think is interesting because we used to be all natural and simple but now it's all scientific,” said senior agriculture major Madeline Morataya.
Avocado Sucker Grafting - After the Fire
When avocados are converted from one variety to another or in the case of severe frost or fire damage and there is still a healthy root system, sucker grafting should be considered. This can lead to more rapid production and is one of the easiest, most successful grafting procedures. It does take considerable attention to the graft and protection from damage by animals and overgrowth from competing suckers.
A detailed presentation of the process is found in a UC publication – Propagating Avocados, authored by Bob Whitsell, Grey Martin, BOB Bergh, Alvin Lypps and Hank Brokaw. This pamphlet was published in 1989 and is still the bible of avocado propagation. It mentions the use of parafilm as a wrapping material. It is now the standard for grafting and budding. Parafilm has pretty much replaced polyvinyl tape and asphalt emulsion for sealing and attaching the scions. It is a strong material, yet readily stretches to allow for bud growth. Where the grafts are exposed to the sun, this tape should also be painted white to protect the growing point from sunburn.
http://www.avocadosource.com/papers/research_articles/whitsellrh1989.pdf
And an older publication by E.O. Stromberg
http://www.avocadosource.com/CAS_Yearbooks/CAS_25_1940/CAS_1940_PG_89-91.pdf
avocado suckers
Growing Fruit Trees, Especially Brown Turkey Figs
Advice from the Help Desk of the
UC Master Gardener Program of Contra Costa County
Client's Request: I need some help with pruning, grafting, and transplanting young fruit trees. I'm especially interested in growing Brown Turkey Figs.
MGCC's Help Desk Response: Thank you for contacting the UC Master Gardener Program Help desk with your questions about pruning, grafting, and transplanting young fruit trees. Some of your questions were answered on the phone and others required some “digging”.
Before pruning any fruit tree, it is important to know its bearing habits, and ultimately what shape or size you would like the tree to be when it reaches maturity. You mentioned that you would like to know how and when to prune the Brown Turkey fig that you bought and planted in a pot last year. You also mentioned that you wanted to know how and when to graft a fig branch (or scion) from your son's tree onto yours.
Grafting a different fig cultivar onto your tree, involves taking scion wood from a healthy tree this winter, and preserving it in a bag with moist peat moss until spring when the grating should be done. Here is a link with detailed instructions about one grafting method you might try.
https://www.gardenguides.com/125489-graft-fig-tree.html
You might also consider getting hands on experience at the Golden Gate Chapter of the California Rare Fruit Growers Scion exchange on January 20th in Berkeley. Here you may take a grafting workshop, as well as finding hundreds of varieties of budwood for grafting and cuttings to root. Please see the following website for more information about the event, as well as its location. http://www.crfg.org/chapters/golden_gate/scionex.htm. (Editor's note: Many years ago, I attended the CRFG's Scion Exchange and brought home scions of 22 different types of figs. I planted them all directly 1 each in gallon containers. They all survived, much to my surprise, since I'm not fond of figs. Fig Newton cookies yes. They eventually all were donated to dia to a much better fate than my garden.)
You also mentioned that you have a two-foot-tall volunteer fig tree in your yard that you'd like to transplant. The best time to dig up and transplant a fig is now during its winter dormancy period. You will need to measure the trunk and calculate that for every inch of trunk diameter, you will need to allow for ten inches of root ball diameter when digging. So, if your tree is 1 inch in diameter you'll have to allow for an almost 1 foot diameter of root ball. You should also dig the root ball at least 1” beyond the canopy of the tree to minimize damage of any lateral roots.
Other important facts when transplanting your fig tree include: planting it in full sun, digging the new hole no deeper than the root ball, using existing soil when back filling the hole, and avoiding planting in areas that collect water, in order to mitigate the possibility of “wet feet”, which might make the tree more susceptible to root rot. Use the following link for a comprehensive guide to fruit tree planting and care. http://homeorchard.ucdavis.edu/8048.pdf
For more all-inclusive information on how to prune, including shaping, types of pruning cuts, and much more, see the following link. http://homeorchard.ucdavis.edu/8057.pdf
This is a lot of information to take in, but I hope that you are successful in your home gardening pursuits, especially for your fig trees.
Help Desk of the UC Master Gardener Program of Contra Costa County (JJM)
Note: The UC Master Gardeners Program of Contra Costa's Help Desk is available year-round to answer your gardening questions. Except for a few holidays, we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 75 Santa Barbara Road, 2d Floor, Pleasant Hill, CA 94523, although we will be moving sometime soon. We will notify you if/when that occurs. We can also be reached via telephone: (925)646-6586, email: ccmg@ucanr.edu, or on the web at http://ccmg.ucanr.edu/Ask_Us/ MGCC Blogs can be found at http://ccmg.ucanr.edu/HortCoCo/ You can also subscribe to the Blog (//ucanr.edu/blogs/CCMGBlog/)
Afer the Fire, Replant or Field Graft?
This is from past experience, and is still relevant. Availability of replant trees is a major issue to consider at this point.
The wildfires in San Diego and Ventura Counties during the fall of 2003 were certainly devastating to many avocado groves adjacent to burning native chaparral. Many of the avocado trees were singed in the canopy without extensive damage to the large scaffold branches; these trees will re-grow new foliage with some relatively minor pruning to clear out smaller dead branches. However, other groves have had extensive damage, complete with charring of the bark in the trunk and boiling of the sap through the bark of the trunk. In these cases, the sap became hot enough to steam the cambium layer (the layer of living cells just beneath the bark), killing the tree above the soil line.
In the latter case, the tree above the soil line is dead, but the roots are still alive. Beginning about the first of March 2004, we have noticed that many of these trees are sending up rootstock suckers near the trunk. If left to grow un-grafted, these suckers will become an avocado tree, but not a known cultivar. The question is: should these burned trees be removed and replanted with a new tree? Or should a sucker be tip-grafted back to a known cultivar?
Sucker grafting in avocado is a well-known practice and has been used extensively in the industry when a grower desired to change cultivars. Generally, the tree is cut down leaving a threefoot stump, which is used as a stake for the new tree. A strong sucker growing from the base of the tree is selected (the sucker should be about 3/4 to 1" in diameter and stiff, not rubbery), and the other smaller suckers should be removed. The sucker is cut with a horizontal cut about 6-8" above the soil line, a 2”vertical slit is made down through the center of the sucker, and 3" to 4" long piece of budwood, cut like an arrowhead at the bottom end, is slipped into the slit, matching the cambium layers together on at least one side, and preferably on both sides. The graft is wrapped tightly with grafting tape, and the entire budstick is wrapped with Parafilm to prevent moisture loss, and grafting tape is used to tie the new grafted sucker to the stump (used as a stake).
Advantages from sucker grafting (as opposed to planting a new tree).
- Sucker grafting is cheaper. As recently quoted by a grafter in Fallbrook, sucker grafting usually costs about $2 per tree after the tree has been cut down to a 3 foot stump. If the grafter supplies the budwood and grafting tape, the price will probably be $2.50 per tree. If the grafter has to travel away from Fallbrook, the price will be higher according to the distance traveled. A new replacement tree will cost about $14 on a seedling rootstock, or $19-22 on a clonal rootstock. The labor cost for planting the new tree would be about $2.00 per tree. These costs do not include cutting down the older burned tree, or follow-up care for the young tree.
- The older, burned avocado tree has an extensive root system with a lot of stored energy. When the sucker graft begins to grow it usually grows very rapidly, much faster than a young replant tree. The sucker grafted tree should start to set fruit two years after grafting.
Disadvantages from sucker grafting.
- We are assuming that the sucker-grafted tree is healthy and does not have root rot or some other disease. If the older tree has root rot, it would be better to remove the old tree and replant with a new tree grown on one of the newer root-rot tolerant clonal rootstocks.
- In the system described above, the trunk is used as a stake. When the new tree grows enough to be selfsupporting, the old stump should be cut down close to the ground. The stump should be slightly sloped to drain water away from the new tree. This takes some careful chainsaw work.
- Suckers. Until the new tree gains strength and starts to shade the old stump, there will be other suckers emerging. These must be removed or they will take over and shade the grafted sucker.
avocado suckers
Invasive Spotlight: Asian Citrus Psyllid and Huanglongbing
If you subscribe to our Pests in the Landscape blog, you'll notice that we frequently post updates...