Xtremehorticulture

Xtremehorticulture of the Desert

Growing Vegetables Vertically Saves Space

Leave a Comment / how to. what to, vertical gardens, vertical growing of vegetables /

Q. I like to decorate my backyard with trellises and would like to grow vegetables vertically. Are   there some late season vegetables I can train up my trellises for fall and winter harvest and when should I plant them? A. Growing plants vertically is a good space saver for smaller backyards and allows you to concentrate production in a smaller area. Allowing vegetable plants with soft fruits, such as tomatoes, to sprawl on the ground increases fruit losses perhaps as much is 30% of total yield. Cucumbers on a wire trellis Speaking first about tomatoes, a very interesting technique developed in Florida for commercial tomato production is called the Florida Weave. You can see how this is done at Wiki How http://www.wikihow.com/Tie-Tomatoes-Using-the-Florida-Weave Some good vegetables to grow by trellising when temperatures cool off toward September include pole beans with two of my favorites being Kentucky Wonder and Blue Lake which have wonderful flavor. They are also available in Bush types but I still think the flavor is better when these varieties are grown on poles or trellises.   Vegetable Trellis on Pinterest Don’t forget to try pole peas such as Sugar Snap where you can eat the pod and the peas (after you remove the string..remember that string?). Another favorite of mine for taste is Lincoln. It can be trellised or grown as a bush but it is a very high producer and great flavor. Trellissing tomato and cucumber in the greenhouse If you want edible pea pods then I would recommend Mammoth (Melting). I also like yardlong beans for growing on trellises. They tend to like warmer weather so planting a bit early should not be a problem. One of the most common varieties is Asparagus yardlong or Chinese yardlong beans. Another I would recommend is the Scarlet Runner Bean. It has beautiful red flowers and the pods are edible or you can shell them when they mature. Trombocino squash trellised Next year when trellising, for fun try the loofa squash which is edible when the fruit is young, about 8 to 10 inches long and used as a loofa sponge when it is mature. It produces some long vines that can be trellised. Another fun one is the trumpet or trumbetta squash which produces a 6 foot squash that is long and straight when trellised and coiled when grown on the ground.

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Holes in Geranium Leaves Probably Tobacco Budworm

Leave a Comment / why are my geraniums not flowering, Why are my petunias not flowering, why do my geraniums have holes in the leaves /

Q. I have two pots of geraniums facing the morning sun under a covered patio. The sun moves away at about 10 am. They look fairly good. I am watering them three times a week and temperatures are 101 to 111 degrees during the day. The plants have beautiful green leaves but they have holes in them. What’s causing this and what can I do to help minimize or eliminate the holes? Corn earworm, Close relative to tobacco budworm A. The damage reported to me by my readers have been primarily on two plants; geraniums and petunias. Both of them reported a loss of color which means they stopped flowering. Tobacco budworm normally infests flower buds and so a loss of color is usually the first thing that is noticed. However, once flowers have been destroyed and occasionally even when they are not destroyed we see damage to the foliage or leaves. It is most likely tobacco budworm which is a close relative of the tomato fruitworm and the corn earworm. These are virtually the same insect but infest different plants. However, the tobacco budworm is a little bit more difficult to control in geraniums. The tobacco budworm normally attacks the flowers and causes the plants to stop blooming. But if there are no flowers to attack, they could go after leaves. This budworm also attacks petunias and causes a loss of flowering. Another little present they leave behind are small black fecal poop on the leaves. This is the larva of a moth so you can try either Bt or Spinosad sprays on the leaves. I think Spinosad will give you better control in my opinion in this particular instance. You can also try a soil drench and spraying the foliage with a synthetic pyrethrum product. These are insecticides that have an active ingredient on the label ending in -thrin. One of these products, or all of them, should give you some control and they are not bad products to have on hand for other things as well. Some further reading on tobacco budworm Fact sheet on tobacco (geranium) budworm from Colorado State University Tobacco budworm on petunias can be managed with Bt in California Agriculture (1992) Updated information from the University of California (2013) Disclaimer Why do I select Information only from Colorado and California? First of all, Colorado State University is my Alma Mater but not only that they are in the arid West and information from Colorado, New Mexico, Utah more closely resembles what is needed in Nevada, or the desert, than information from Florida or Minnesota. Information from California is needed by Mojave Desert residents because many of the plant materials grown in the Western deserts were purchased and exported from California. It is always best to obtain information from valid sources in climates that are similar to your own.

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Seeds in Raised Beds Not Germinating

Leave a Comment / germinating vegetable seeds, Why are my vegetable seeds not germinating /

Q. I have a problem in my raised beds I never encountered before. I can’t get seeds to germinate in two of them this year. I have grown produce in them before and the only difference is that I added a lot of oak leaves and clippings from my sage plants this year. I purchased new seeds and replanted but nothing is coming up. A. The oak leaves and sage clippings would have little effect on the germination of vegetable seeds. Most likely, if it did have an effect you would see very uneven germination of the seed. If you are trying to germinate seeds in the middle of our hot summer in full sun the usual problem is that the soil dries too quickly and prevents seeds from germinating. Seeds need to stay wet for several hours in order to start the germination process. If you are going to plant seed during hot weather, plant it at dusk and water them in thoroughly so that the seeds have all night to absorb water before the heat of the following day. This time of year water can be lost from soil at a rate of over 4/10 of an inch a day. Seeds, small seeds in particular, are covered with a very shallow layer of soil. Unless you are watering that soil several times a day, the soil and the seed will dry out causing germination failure. Covering the soil with shade may be enough to get the seeds to germinate. I use horse bedding or straw to cover the soil after seeding during summer months so that the soil does not dry out so rapidly. Horse bedding used to improve seed germination and rooting in summer months Where to get horse bedding for mulch Horse bedding and straw are very porous but they also shade the soil and slow evaporation. I like horse bedding more because it can be turned under at the end of the growing season more easily than straw and it decomposes faster. With large seed such as corn, peas or beans, soak the seed for several hours indoors before planting them out of doors. Again, plant at dusk during hot summer months, not in the morning. This allows seed to absorb water at night before getting hit with the sun in the morning. You can also pre-germinate very small seed but it is more difficult. The seed is soaked in water for several hours and then dried on paper towels. The seed must absorb or imbibe the water but before the seed sprouts. Drying the surface of the seed will not kill the seed as long as it is planted very soon after drying the seed surface. If you soak seed in water, dry it and then do not planted for several hours it is possible to kill the seed. If you leave the seed too long and water and it begins to sprout, the seedling is very delicate at this stage of growth. The first to emerge from the seed is the young root or radical. If you are not gentle with the seed you will break this young root off from the seedling and the seedling will die. More remote possibilities could be very high salt levels if compost were added to the soil or planting transplants or seedlings into soil which is too dry. This will also damage or kill seedlings and new transplants but the germination should be spotty. I think it is most likely a watering issue and not keeping the soil moist during seed germination.

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How to Stop Galls on Oak Leaves

Leave a Comment / Fuzz balls on leaves, how do I stop weird growth on leaves of oak, leaf growths, leaf warts, What causes galls on oak leaves /

Q. I am inquiring about wasp galls on the underside of oak leaves. I am in the commercial tree business. Any control measures that have been found to minimize the wasp from laying the eggs or stop the oak from forming the fuzz ball? As I recall the fuzz ball is reaction from the oak defending itself. Any information would be greatly appreciated. Oak leaf gall A. Plant leaf galls can be caused by fungi, bacteria and insects like aphids, moths, midges, wasps as well as mites. You can identify what caused the gall by its shape and color and the host plant. In this particular case, if we are seeing the same picture in our minds, you are right, it is caused by egg laying of a tiny wasp. Poplar flower gall caused by tiny mites Many times it is only a specific insect or fungus that inhabits a specific species of oak or plant. If you had a picture we could take it further. I remember seeing some leaf galls on native oaks in the spring mountain range here. I assume they were caused by wasps as well. Galls produced on plants are unique to the organism that caused it. Sometimes it is caused by feeding damage, infection or reproduction. The pairing of an insect or fungus with a specific species or type of oak in this instance is frequently unique. oak gall causing leaf drop A guy who is done a lot of work in this area and in our part of the world is Ron Russo, a naturalist. Here is a page taken from Natural History Magazine published in 2009. Plant galls click here I have been telling people to appreciate nature and live with it. Unless it’s really causing problems like defoliation I would leave it alone. I guess if I had to treat it I would probably use something like imidacloprid as a soil drench when new leaves are beginning to form. The problem in treating for this insect is that we don’t know it’s lifecycle. So we don’t know when it is laying its eggs to put down a protective spray. I feel that a soil drench will give the plant longer protection and is less of a problem to the environment. But I would really resist using this insecticide unless I was forced to use it by the client. Environmental concerns surrounding this product, in my opinion, don’t justify its use unless it’s under extreme conditions. And even if you do use an insecticide like this the old leaves will still have the galls and it will only protect new growth. I will post your question and my response on my blog next week and you can direct anyone with questions to that spot. 

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Gibberellic Acid on Grapes Can Make Larger Berries

4 Comments / how to prepare gibberellic acid, How to use gibberellic acid with grapes, increasing berry size of grapes /

Comment from Reader:  Amazing results with Gibberellin on grapes.  Red Flame are double last years size and the Thompson’s. and at least triple.  I used 50 ppm solution and hand sprayed bunches on 1/2 the vine and left the other 1/2 without.  Those sprayed way out did the non-sprayed.  I used the same method on stone fruit and saw no favorable results.  I will try a more concentrate on the stone fruit next year.  Prudent pruning, thinning and mulching were used.  Thanks for the Gibberellin suggestion in a previous article. My comments to the reader: This is something I wrote for a nonprofit organization several years ago on gibberellic acid. I realize it is more than most people will want to know but pick and choose what you like otherwise it will be lost forever.Gibberellic acid can be quite expensive so some of you might want to band together and buy it collectively and share it. Uses of Gibberellic Acid Robert L. Morris March 10, 2009 Gibberellic acid (also called Gibberellin A3, GA, and (GA3) is a hormone found in plants. Gibberellic acid is a very potent hormone whose natural occurrence in plants controls their development. Gibberellic acid promotes growth and elongation of cells. It affects decomposition of plants and helps plants grow if used in small amounts, but eventually plants develop tolerance for it. Gibberellic acid stimulates the cells of germinating seeds. Since GA regulates growth, applications of very low concentrations can have a profound effect while too much will have the opposite effect. It is usually used in concentrations between 0.01-10mg/L. Gibberellins have a number of effects on plant development including rapid stem and root growth and increase seed germination rate. Gibberellins are used in agriculture for various purposes. GA-3 is sprayed on seedless grapes to increase grape size and yield, and it is used on navel oranges, lemons, blueberries, sweet and tart cherries, artichokes and other crops to decrease or increase fruit set, delay rind aging, etc. These effects are highly dependent on concentration and stage of plant growth. GA is used to trigger flowering of sweet potatoes in breeding programs, to help tomatoes set fruit at high temperatures in the tropics, overcomes the need for chilling or long days to trigger flowering, and so is used in the tropics for breeding. Developing seeds are active sites of containing GA and studies have found increases in GA levels in seeds during germination. The germination of old seeds has been improved with use of GA. Applied GA-3 may trigger dormant seed germination, in many cases overcoming the need for special or prolonged dormancy-breaking conditions such as cold treatment, light, after-ripening, etc. Gibberellic acid is sometimes used in laboratory and greenhouse settings to stimulate germination in seeds that would otherwise remain dormant. It is also widely used in the grape-growing industry as a hormone to induce the production of larger bundles and bigger grapes, especially Thompson seedless grapes. In the Okanagan and Creston Valleys of Canada it is used in the cherry industry as a growth regulator. Effects of Gibberellic Acid Overcoming dormancy. Treatment with high concentrations of GA is effective in overcoming dormancy and causing rapid germination of seed. Premature flowering. If a plant is sufficiently developed, premature flowering may be induced by direct application of GA to young plants. Increased fruit set. When there is difficulty with fruit set because of incomplete pollination, GA may be effectively used to increase fruit set. The resulting fruit maybe partially or entirely seedless. GA has increased the total yield in greenhouse tomato crops both as a result of increased fruit set and more rapid growth of the fruit. Hybridizing. Pollination within self-incompatible clones and between closely related species may sometimes be forced by the application of GA and cytokinin to the blooms at the time of hand pollination. Increased growth. GA applied near the terminal bud of trees may increase the rate of growth by stimulating more or less constant growth during the season. Frost protection. Spraying fruit trees at full-blossom or when the blossoms begin to wither can offset the detrimental effects of frost. Root formation. GA inhibits the formation of roots in cuttings. Recipes Although GA is not listed as a “poison”, the following precautions should be observed: Flush with water any GA that may get into the eye. Avoid skin contact if possible. If skin contact is suspected, wash with soap and water. Do not re-enter an area after spraying until the GA spray is fully dry. Avoid ingestion of GA. The powder may be dissolved as specified below to give the desired concentration. Concentration parts/million GA mg Water ml (cup) Purpose 50 125 2400 (10 1/2) Early flowering 200 125 600 (2 1/2) Early flowering 800 125 160 (2/3) Blossom set 2000 125 60 (1/4) Seed germination 1% paste 125 5 ml (1 tsp.) lanolin Growth promoter Thinning and Increasing the Size of Table Grapes In varieties like Thompson Seedless, Flame Seedless, Perlette and a few other varieties (seedless grapes primarily) GA3 (gibberellic acid) is used for either thinning out the number of flowers which set fruit, a bloom thinning spray, or for increasing the size of the berries (referred to as a sizing spray which is applied about one week following bloom). In some varieties both a bloom spray and one or two sizing sprays are generally applied. Not all varieties respond to bloom sprays for thinning. These varieties may use a gibberellin spray only for increasing the size of the berry. Grapes which produce seeds are generally larger than seedless grapes because seeds produce natural gibberellins which increase the size of the berries. One must be extremely careful when using GA3 on grapes. Each variety has a different tolerance level and one should not ‘experiment” or use more of the material than is recommended for any given variety. The gibberellin produced for commercial use in grapes is manufactured by Abbott Laboratories, Merck, and Agtrol. It is produced in both a powder formulation and

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Avoid Transplanting Beans into the Garden

1 Comment / pole beans, Why are my beans not producing /

Collar rot on been planted in cold soils Q. I just read your recent article regarding pole beans. I am not having much luck with them. I planted seeds (Kentucky and Blue Lake) the last week of February in my green house and then transplanted to raised bed the first week of April. The vines have grown like weeds and are very lush, but there are no beans. There are blossoms, but I do not see much bee activity. Any suggestions for next year? A. Usually beans are not transplanted. The roots of beans are somewhat fragile and they will not transplant easily. Normally they are direct seeded into the garden as soon as soil temperatures are warm enough in the spring or, when temperatures are cool enough in the early fall. We have a long growing season so we can get both a spring and fall crop here. When soil temperatures are warm enough for germination usually are air temperatures are also warm enough for good growth and fruit set by the time they get larger. Growing them in the greenhouse and putting them out in the garden may be a bit early for them to be productive and they might get damaged. For beans to set fruit it’s best if air temperatures do not drop the low 55° F at night. In a warm microclimate, South or West facing and protected from wind, you could probably plant in February. If you are in a normal microclimate then delay planting until March. If we get cold air temperatures the flowers will drop off without setting. Likewise, when we plant beans too late in the spring, they will struggle to produce beans at temperatures above 90° F. Try pole beans again this fall but plant the seed in the middle to latter part of July at about a 1 inch planting depth. This will give them some time to get up in size and begin flowering when we start entering cooler temperatures of late summer and early fall. Beans struggling with growth in the row because of collar rot Soils warm early if they are loose and in full sun. We keep the soils loose by adding compost to improve the aeration of the soil, or the amount and size of airspaces between soil particles. A good starter fertilizer for beans will be high in phosphorus and lower nitrogen. Another factor that can affect production in a garden is wind. If the garden area is in a windy location this may affect production particularly of those vegetables that rely on pollination through the air or by insects. I realize you were trying to get an early start on them by germinating them in the greenhouse but putting them into cold garden soils can create a problem with root diseases, particularly collar rot and root rot diseases. If you want some early germination in the spring, I would suggest adding compost first and then warming the soil with strips of clear plastic about 18 inches wide for a week before planting. Cut slits in the plastic after one week and plant directly into the warm soil without removing the plastic. Fall vegetables to try

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Possible to Stop Berries Produced by Palms

4 Comments / berries from palms, how to stop berries from palm trees, litter from palms /

Q. My palm trees continuously produce berries. I keep cutting them off but they come back. Even the new 1-year-old palms I planted have green berries on them.  Is there any way to keep them off?  Are there palms that do NOT produce berries? A. Production of these berries or fruits and dropping them on the ground is a natural occurrence every year on all palms. They produce flowers on long stalks, the flowers become fruits or berries and they drop from the tree and litter the ground. This is a major objection to palms growing near swimming pools. Once a palm is old enough for flowering, it will continue to flower and fruit every year. There is nothing that you can do to prevent the sequence of events leading up to the production of these berries. There are no chemicals you can apply to prevent this from happening. However, there is one simple thing you can do. When it is ready to begin flowering you will see stems growing from the trunk. When they are long enough, cut off them off with a pruning shears. Flowers emerging from Canary Island date palm in the spring. Cutting off these flower stems prevents the production of fruit and will not harm the palm. If the palm is too tall, use a pole pruner to cut them off or a ladder and a loppers. These flowers will make thousands of “berries” that will drop to the ground. Cut off the flower stalks with a loppers or pole pruner. If you want it done commercially, coordinate the pruning of your palm at the same time it produces flowers and cut them off at the same time the palm is pruned.

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Rings on Peach Fruit May Be Disease, Frost

Leave a Comment / frost damage of peach, powdery mildew of peach, Virus diseases of peach /

Q. What is wrong with my peaches? I left you a voicemail. I’m not much of an e mailer. These peaches are 30 miles south of Mesquite. Around 4500 elevation. The spots showed up essentially as the peaches formed.  A. And I am not much of a phone person. I am working outside of the country right and I did get your voicemail but responding to you is easier for me through email. It allows me to collect my thoughts and gives you a written record of my thoughts and recommendations. This is not something I have seen before on peach fruit. I have seen something similar to this on apricot. The things that jump out at me are your location south of Mesquite and your 4500 foot elevation. Three things came to mind when I saw the picture; virus disease, early spring frost damage or powdery mildew or similar disease developing on the fruit during cool, wet weather. You didn’t tell me if you’ve seen it in previous years but if this were a virus disease you would’ve seen it before. The fact that you did not mention that it leads me to believe this may be a one-shot problem and not one that is reoccurring. This kind of eliminates virus diseases. But your pictures very closely resemble a virus problem.  Peach Virus Diseases Click Here! Although it really does not resemble late frost damage too much, because of your elevation, I am thinking it might be a possibility. All it would take is some temperatures slightly below freezing for an hour or even less just as the fruit were forming. Frost damage might cause some fruit drop while damaging others and not affecting others that remain on the tree.  Frost Damage to Peach when it reaches near maturity There is a microclimate in the tree fruit canopy that can affect frost damage severity for the entire tree. If this were freeze damage to immature fruit I would suspect it would be more of a problem on the north side of the tree, fruit exposed to windy locations or at the top of the tree rather than lower and inside the canopy. Diseases like powdery mildew can leave this kind of a mark on immature fruit. It would have occurred during or slightly after rainy or wet weather and on fruit that were protected from wind by leaves or inside the canopy of the tree. Fruit in areas exposed to full sunlight and lots of air movement would, most likely, have fewer problems. Perhaps powdery mildew on apricot If this were a virus disease, it could have been brought in with the tree when it was purchased. It is also possible that the tree was infected by neighboring trees with the same virus. The third possibility, if the tree was grown from a pit or seed, the seed could have come from an infected tree. Virus diseases of fruit trees are usually a problem when people do not purchase “clean” nursery stock. Make sure you purchase fruit trees from nurseries that are using and producing plant materials that are certified free from diseases. Perhaps powdery mildew on apricot If you grow your own fruit trees from pits or seeds, disease problems like this are always a possibility. It may be rare, but it does happen. If you planted from seed and you think this may be a virus disease, there is not much you can do except live with it or replace the tree. If you decide to live with it, it is possible the disease could spread to other plant materials in the Orchard or your neighbors. If you think this may have been a disease problem such as powdery mildew or close relative, make sure your peach trees are not growing close to apple trees which may contribute to the problem. If you think this is a disease problem that is not a virus, you should prune open the canopy more so that there is better air circulation and light penetration inside the canopy. Secondly, spray with sulfur applications shortly after rainy or very wet weather to help prevent the disease from developing on fruit.

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Clark County Code 30.64.030 Restricting Hardscape to 60%

Leave a Comment / Clark County Nevada, County code, County restrictions, hard scape, Hardscapes /

Q. If Clark County Code 30.64.030 restricts hardscape to 60 % which includes paved areas, pavers, rocks, stones, etc where does xeriscape fit into this issue, please? A. It is my understanding that hardscape does not include mulches (rock mulch used for desert landscaping). These are not permanent features of a landscape such as drives, sidewalks, decking. etc.  I think the point that concerns the government is that they do not want someone coming in and paving the entire landscape to save water, reduce maintenance, etc.  Hardscapes increase surface runoff to storm sewer systems and add pressure to waste water treatment facilities and a number of other issues. However, I was not a part of this discussion and really not qualified to address it. Perhaps someone who is closer to the government issues and county codes can address this better than I can.

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During Hot Weather Increase How Often You Water, Not How Much

Leave a Comment / how much should I increase my watering in hot weather, How often to water trees and shrubs, irrigation of trees and shrubs /

Q. With the temps averaging 110 F, how much and often should I be watering my shrubs and trees? A. I would normally not increase the number of minutes on an irrigation clock but add one more watering day each week as it gets hotter. I would not recommend changing the number of minutes under normal circumstances but the number of watering days in the week. You seldom change the number of minutes on an irrigation clock after you are satisfied with your landscape irrigations. The number of minutes on an irrigation clock delivers a set volume of water during a cycle and it does it the same every time it comes on. This set volume of water fills the same volume of soil every time for every plant on that valve or station. This set volume of water wets the soil to the same soil depth and same spread every time it comes on. It’s like filling a gas tank on a car. This wetted soil supplies water to plant roots. Each time after an irrigation, that specific volume of water fills the soil to the same depth and width every time. Roots grow into these areas to get the water they need. Plant roots dominate the wetted soil where there is irrigation water. They do not grow into areas where there is little to no water. As temperatures increase, the amount of water needed by plants also increases and they consume water in the soil more quickly. Relating back to a gas tank of a car, we fill the soil with water again when the “gas tank” is about half empty. This means as temperatures get hotter we must fill the soil with water more often. This jump from 100F to 110F (10° F change) seems big to us but it is not as big as the jump as the jump from February to June (30 to 40° F). Usually an increase of one day each week, or about 20 to 30%, is enough to handle a 10% increase F in temperature.

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