Xtremehorticulture

Think Twice About Planting Pecan in the Desert

Q. We want to plant a pecan tree. Would you please recommend one for Las Vegas? If we plant one, can we cut it way back and keep it small like we did our other fruit trees? A. Think twice about it. Pecan is a big tree requiring lots of water. If you want to proceed, then pick a Western variety that is self-fruitful and low chill such as Mahan, Mohawk, Tejas or Western Schley.             Pecans are so big that cutting them back may result in a tree that is about 2/3 of its mature size, maybe 60 to 100 feet tall, but you will not get it much smaller than this. The reason you can keep trees like almonds and pistachios small is because they are not big trees to begin with. The larger fruit trees, like apple and pear, are usually put on dwarfing rootstocks.             Pecan is a big tree and is not on any dwarfing rootstock so it will be hard to keep its size small. Pecans tend to get anywhere from 70 to 150 feet tall and can have a 6 foot diameter trunk. Normal spacing between pecans is 60 feet apart. Estimating Water Use for Pecan Trees

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Siamese Twin Peaches; Double and Triple Peach Fruits

Double and triple peaches Q. I have small peach fruits now on my newly planted peach tree and some of the fruit are like Siamese twins; there are double fruits coming from the same spot. In some cases there are three fruits. A. Double peaches are thought to be from drought stress at the time of flower bud formation which would have been from last July or August (2011). Double peach mature Double apple Double fig             I usually remove one of the “doubles” so that, when possible, only one fruit remains.  You have to do this when the fruit are young and small and they can still recover. The remaining fruit will heal if the damage is not severe. If the double fruit cannot be split apart then remove the entire fruit.             At this stage of your tree’s life I would probably leave only a handful of fruit on the tree depending on its size. I would estimate that about 50 leaves are needed to support one fruit. I am not asking you to count the leaves but just estimate it when determining how much fruit to leave on a branch.

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Caliche May Determine How to Plant Fruit Trees

A caliche rock at the orchard Q. While preparing my holes to plant my fruit trees I encountered caliche.   I’m able to dig down to about 18” by 24” across. I filled the hole about half way with water and the next morning it was all gone. Everything I read discourages planting over caliche. I was thinking of barrels. A. You are fine with a depth that will accommodate the root system (18 inches deep) as long as you have good drainage. Go ahead and plant. As long as these are smaller fruit trees (less than 20 foot or so) you will be fine. They could get by with 12 inches (I would rather see it deeper) if they have to as long as you have good drainage. I would not put them in barrels unless you had too.

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When to Fertilize Fruit Trees Including Citrus and Grapevines

Q. Is there a recommended schedule for fertilizing fruit trees in the valley?  Also for citrus and grapevines?  The schedules I’ve read for each of these are differ depending upon who wrote the article and are not specific for the valley. Fertilizer applied around the source of water to the fruit tree, in this case a bubbler which will wash the fertilizer into the root zone A. It does not make that much difference as long as the plant has nutrients available during times of fruit production and fruit bud development but generally speaking we avoid applications which might encourage a flush of succulent growth just before winter sets in. This just means try not to apply fertilizers after about mid-July.             You can get by with a one-time fertilization in the early spring (January) for most fruit trees if you want to. The next thing you can do is a half application in the spring (January) and the other half after harvesting the fruit. Here fertilizer stakes are pounded into the soil close to the source of water going to the tree but not close to the tree itself             The third way is very light applications of fertilizer sprayed on the foliage or leaves of the trees, monthly, suspending applications from August – November as the tree sets up for winter dormancy. I usually use one of the granular fertilizers that dissolve totally in water such as Miracle Gro or your favorite organic liquid fertilizer. We fertilize just about all our fruit trees and vines once in January with a soil application and that’s it.

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Star Jasmine Stopped Blooming? Cut it Back Hard

Q. My gorgeous, dark green, full and old Jasmine has stopped blooming.  I have tried several remedies and none has worked. Can you give me some pointers to get back the heavenly white fragrant blossoms? Star jasmine A. By jasmine I take it to mean star jasmine. This vine can also be used as a ground cover and must be supported on a trellis if used as a vine. It blooms in the spring only and so it may not be the time of year for it yet.             Just be patient. There is no secret formula. Fertilize with any good fertilizer for flowering shrubs in early spring (January through February or now even).             Be careful when pruning you do not prune out flowering wood. Do your pruning immediately after flowering is finished, not during the winter unless you know where the flowering wood is located.             An old horticultural adage is that if a plant is not performing well and you are considering getting rid of it then cut it back hard. Of course this will damage flowering for awhile but you may get the plants “attention” and they will sometimes respond very positively.

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Borers in Fruit Trees and Buggy Grapevines

Q. Through the years I have planted many fruit trees and lost many to borers especially stone fruit trees. My grape vines have been devastated by whiteflies to the point where I could not harvest one healthy grape leaf last season. I have tried soap water but to no avail. Also, I have tried Lindane against borers but their work keeps appearing on my plum trees. A. Whiteflies can be a difficult problem. We have not experienced whiteflies on grapes. The closest insect which might be confused with whiteflies, and is a common problem on grapes, are leaf hoppers. Please make sure you are not confusing whiteflies with leaf hoppers because the treatment is very, very different. Whiteflies are like dandruff and usually fly in a cloud of small white insects when the leaves are disturbed. They usually leave a sticky substance on the leaf surface from feeding. Click here to see some Whitefly pictures Leafhoppers on their backs, maybe 1/8 inch long Leaf hoppers on the other hand jump and are brown in color but they can accumulate in thousands on grapes and jump in your face, your nostrils and eyes as you pass the grapes and disturb the foliage. Both are nearly the same size but whiteflies are white and fly more delicately while leaf hoppers jump and are brown. If soap and water sprays are used religiously on the grapes when these insects are small it should give fairly good control. If soap and water is delayed until they are mature adults, then control is probably iffy at best. Whiteflies are listed on the University of California and pests lists for grapes but not a common pest. Leafhopper feeding damage on grapes Click here to learn the Common Pests of Grapes If they are whiteflies then sprays such as pyrethrins might be a good choice but the label must include grapes if you are to use it within the law. If these are leaf hoppers, then sprays applied in May such as spinosad might be useful when this insect is still juvenile. In both cases when these insects are adults they are much more difficult to control. Sap oozing from cut limb of plum Regarding the borers in your plum tree, Plum can be attacked by boring insects but it is not as common as some other fruit trees like peach, nectarine or even apple. Please check and make sure that this is in fact borers causing damage and not just sap oozing from a stressed out tree. When plum is stressed from water, intense sunlight or heat stress they will ooze sap. There is no insecticide you can use on fruit trees once they are attacked by boring insects and still safely eat the fruit in my opinion. Most insecticides recommended after fruit trees have been infested are usually systemic in nature. This means that the insecticide could also be in the fruit, not just on the surface.

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Tumors on Cherry Trees and Bioengineering

Q. I have a problem on some fruit trees on a property I have in Tonopah. These cherry trees have large swellings like tumors on the trunk. I spoke with some nursery people in California and described the problem and they knew what the problem was immediately.              She concurred with me to get rid of the tree and the nearby rose bush because the rose bush carried the disease and transferred it to both of the fruit trees.  The cherry I chopped down as it was dead all the way through. She told me the whole and area around it would be bacteria infested for a while and even if I put in the soil the product she gave me to kill algae and bacteria, it might still come back. A. The only thing I can think of that comes close to your description is a relatively benign disease called crown gall. And this is probably what your cherry tree has. This bacterium does infest the soil. It is not typically transferred from plant to plant so getting rid of the roses is not necessary.  A healthy tree can become infested if contaminated soil comes in contact with a fresh wound of the plant.             Actually this is a very interesting plant disease and was used in the early pioneering days of genetic engineering. When plant tissue is infected with this bacterium the plant cells multiply uncontrollably producing a large woody or corky “tumor’ or swelling on the trunk or roots. The reason it is called “crown” gall is the typical site which the gall or tumor is seen.             The crown of a plant is the general location where the trunk meets the soil. However these “tumors” can appear less commonly on roots and stems as well. I will try to post more about this disease and how it is used in genetic engineering on my blog.             Plants can live for many years with crown gall and appear to be quite healthy. It is possible I guess to transmit it from plant to plant by cutting into the crown gall and then cutting another plant with the same unsanitized tool but otherwise you will not transmit it. The usual method whereby it infests a plant is from contact of infested soil with a fresh wound, usually at the time of planting. Images of Crown Gall Open publication – Free publishing – More bioengineering

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Orchard April Todo List

This is what you are trying to avoid by thinning apples Apple before thinning •     Thin fruit, apples and pears. You should be removing or thinning fruit so that the resulting fruit receives more “food” reserves from the leaves and gets larger. The larger the fruit, the greater the distance between them. Nut trees are normally not thinned. Leave one fruit per cluster in apples and European pears. Peaches and nectarines are four to six inches apart. Asian pears are thinned very early; sometimes in the flowering stages if you know you have had good fruit set in the past; perhaps leaving no more than one fruit a foot apart if you want Japanese-style large fruit. Apple after thinng •     Apply calcium chloride sprays to pears and apples susceptible to bitter pit or corky spot, five times in the spring, spaced about one to two weeks apart. Bitter pit or corky spot might appear on Comice pears and Mutsu apples for instance. These are sunken brown spots in the flesh just under the skin. Food grade calcium chloride is applied as a spray to the tree (focused on spraying the fruit) along with a wetting agent to aid in absorption through the skin of the fruit. Corky spot in Comice pear •     Thin corn to 12 inches apart. I like to plant seed fairly close together in March and then remove plants so the remaining plants are 12 inches apart in the rows. No, you cannot replant these plants to fill voids. Kernels in the ears fill in better if you have a minimum of three rows of corn since they are wind pollinated. Corn likes lots of nitrogen fertilizer applied frequently. •     Weeding. Stay on top of your weeds and remove them as soon as you see them. •     Flower thinning of Asian pears. Mentioned earlier. •     Harvest asparagus daily. Now that it is getting warmer the spears are growing faster and need to be harvested more often. You should stop harvesting asparagus after about 8 to ten weeks of removing spears. After harvest you must let the spears mature (let the spears become that five foot tall, ferny growth) which is cut down in December or January. •     Wind protection on the emerging corn. If we get some high winds this time of year and you planted corn in a potentially windy location the wind can flatten your corn rows. A wind barrier such as some fencing like chain link with pvc slats or chicken wire with vines can prevent this from happening. Pull or cut off onion flowers •     Mulch. As temperatures rise and with our low humidity surface mulches can help keep seeds planted in the summer from drying out and not emerging. Straw, shredded paper and other surface mulches can preserve soil moisture and aid in more complete germination. Presoak large seed for 12 hours in cool water prior to planting. •     Fertilize corn every four weeks. •     Pull onion flowers. Remove any flowers from onion plants and use them in cooking or as garnishes to keep them from robbing energy from developing onion bulbs. •     Mulch garlic and onions. Mulching garlic and onions before it gets hot will aid in getting larger bulbs and reduce stress. •     Fertilize onions and garlic and all vegetables in the ground every 3 to 4 weeks. If you used a good fertilizer at the time of planting then all you need is a high nitrogen fertilizer. If you used compost or decomposed manures you may be able to skip these applications. •     Harvest beets and peas. Peas and other cool season vegetables are coming to the end of their growing season. Replant in mid fall. Pheremone winged trap in tree. Pheremone lure is orange inside the trap. •                  Set pheromone traps for peach twig borer (PTB). PTB causes wormy peaches, nectarines and apricots. You first see their evidence on the occasional death of new growing shoots on these trees. Traps help you to reduce their populations or determine when or if spraying is required. I would suggest purchasing lures and complete wing traps from Alpha Scents: (http://www.alphascents.com/Lures/lures.html; http://www.alphascents.com/Traps/traps.html#wing ) Insects caught on sticky insert on the bottom of winged trap. Here the lure is hung from the bottom of the top of the trap. I prefer placing directly on the sticky bottom instead. •     Spray for peach twig borer if necessary using BT sprays or spinosad. •     Spray for Western flower thrips on nectarines using spinosad. •     Spray insecticidal soap for artichokes and aphids. Spray the upper and lower surfaces of the leaves. •     Stake tomatoes, peppers to keep fruits from lying on the ground. Expect more fruit losses if plants are allowed to sprawl on the soil surface. Green almond stage for harvesting immature nut •     Mulch tomatoes, peppers, eggplant. These plants will benefit from surface mulches. •     Label vegetables in vegetable plots. Keep track of what varieties you are planting so you know which ones to purchase or not to purchase in the future. Immature almond nut in the “green” stage •     Green almond harvest. Almonds can be harvested green when they are very small (1/2 inch long) and the entire small green nut can be eaten raw or in salads or allow the nut to enlarge and harvest the immature nut for salads or cooking such as stir fry. •     Young garlic harvest. If garlic was planted 2 inches apart in the fall you can now harvest immature garlic (before the bulbs have enlarged) and use them for roasting or grilling resulting in the remaining garlic plants four inches apart and harvested when fully mature in May or early June. Young garlic stage •     Fix irrigation leaks. •     Prune palms. •     Reapply iron where necessary or spray iron. If you see some trees or grape vines starting to yellow on new growth then reapply iron chelate to the soil now. Spraying fruit trees now with iron may result if iron-stained fruit. •     Dig up

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Orange Tree Leaves Losing Green Color (Yellowing) With Green Veins

Q. I have 9 orange trees on my property and pamper them like my “kids”.  One of them (perhaps two) is losing the green color in the leaves although the veins are staying green in color.  I would like to send you a couple of leaves for your inspection as I have tried to trouble shoot the problem using the computer and pictures. A local nursery disagrees with my request for manganese sulfate to resolve the problem. Would you send me an address so that I can send a few leaves for your inspection and suggestions? A. A picture of the leaves will work just as well as sending me a sample. I will be out of the country and so samples will probably not reach me.             Nine times out of 10 a yellowing leaf with green veins, particularly if it is the newer growth at the ends of the branches, is iron chlorosis and not typically manganese or zinc. The manganese sulfate would be used for a manganese deficiency or you could use a manganese chelate.             You can sometimes take an iron solution with a few drops of Ivory liquid detergent and, making sure the iron solution is slightly acidic with a little bit of vinegar, dip the leaves in the solution for a few minutes. You should see a color change in the leaves in about 24 hours or less.             Otherwise you can take some liquid iron chelate with a little bit of detergent like Ivory liquid and spray the leaves three or four times over a period of a couple of days. This will also turn them a darker green if it is iron.             If it is something other than iron, it won’t do anything. Then go ahead and try your manganese application.             If this color change occurred during the winter it is possible it could be cold damage. This appears more like a bronzing of the leaves rather than yellowing. I hope this helps.

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Planting Ocotillos So They Don’t Die

Q. Ocotillos, the most beautiful plant in Nevada. I have tried twice to grow this and not even one sign of life in 5 years. Now I’m trying at a different home.  I wonder where am I failing?             The soil is mostly poor in Henderson and sandy. I have lots of sun but I avoid western afternoon sun. I also have an area with partial shade. Is this a failure to properly fertilize?  Watering?  A local nursery indicates I’m doing it correctly but it is a tricky plant. (Now they tell me).        A. These ARE tricky plants and not easy to transplant if you are not familiar in dealing with desert plants and cacti. It is also possible to pick up dead plants from the nursery. When they have no growth on them it is very difficult to tell if they are living or not.             One method you can use is the thumbnail method. You can use your thumbnail and scrape a small layer of bark from the stem. It should be green under it and scrape away fairly easily. If it does not, or it is brown under it, then it very well could be dead.             If you want to know if the plant is at all alive, check in several places including near the base closest to where the soil would be and look for green as well. When planting it, make sure it is securely staked into the soil so the roots do not move.             Water around the base of the plant no more frequently than about once every two weeks during the summer. These plants are easily propagated or started as cuttings, stem pieces cut and planted directly into the soil. The trick is not to water so often the stem rots and dies.             I attached a pamphlet on how to establish ocotillo from the Tucson Cactus Society. I am not a big proponent of wetting the canes but the Tucson cactus society is. www.tucsoncactus.org/pdf_files/TCSS_Ocotillo_Planting.pdf Planting Ocotillo –

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