xtremehorticulture – Page 108 – Xtremehorticulture

Let’s Get Ready to Prune Fruit Trees!

Q. Can I prune fruit trees now or do I need to wait until they are dormant in January? Will you be giving fruit tree pruning classes again this year? A. Prune fruit trees lightly with a hand pruner any time there is a problem at any time during the year. Heavy pruning that requires a saw or loppers should be done during winter months after leaves have dropped. Hand pruner or hand shears for making cuts less than 1 inch in diameter Removal of limbs with loppers or a saw is easier after leaf drop when you can see the arrangement of limbs and branches and where to cut. Avoid using loppers or a saw during summer months because of sunburn and damage to the trees by our intense sunlight. Loppers used for large cuts greater than 1 inch. The maximum size for a lopper depends on the lopper and how well it’s maintained and the person doing the pruning. Some people are not physically capable of making some larger cuts. Once cleaned and sanitized, they should never be placed on the ground because of sanitation. The majority of pruning cuts for fruit trees will remove entire limbs and not leaving “stubs” where branches are cut off. Many of the desirable pruning cuts remove vertical growth, upward or downward, which produce little to no fruit and interfere with light entering the canopy. One of my favorite tools for cutting large limbs is a Sawzall with the appropriate pruning blade. I will offer pruning classes of fruit trees on Saturdays beginning in mid-December. Watch the newspaper or my blog for exact dates and locations.

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Fertilizers: Pay for Convenience or Do-It-Yourself?

Leave a Comment / acid loving plants, cactus, citrus, Fertilizers for cacti / xtremehorticulture

Q. What are the year-long fertilizer requirements for landscape plants ranging from acid loving to desert lovers such as cacti, palms and other plants to beautify home landscapes. Many cactus lovers swear byproducts such as cactus juice but most cacti do quite well with a variety of different types of fertilizers A. Desert gardening and horticulture is more difficult to practice than traditional horticulture talked about on most blogs, information sheets, YouTube videos, books and other places. Most information in the media is derived from “traditional horticulture” and these practices may or may not work in the desert. This powdered fertilizer meant for dry or liquid applications has combined fertilizers that create more acidity than some other types. But it has other fertilizers in it as well good for acid loving plants. When applying fertilizers to landscapes in desert climates and soils, consider soil improvement and irrigation beforehand. Soil improvement, where and when needed, solves many fertilizer issues. A good citrus fertilizer that can be mimicked by combining other fertilizers less expensive. But it’s convenience and knowledge that make the sale for most homeowners. The biggest mistake made by desert horticulturists and gardeners is a lack of soil improvement to desert soils when and where needed. Desert soil improvement solves 90% of the fertilizer and irrigation issues in residential landscapes. Because the majority of plants grown in desert landscapes are NOT desert plants. Compost is a great all around fertilizer for most plants. It contains dozens of different minerals and elements not found in commercial fertilizers. Besides that, good compost is biologically active and help stimulate microorganisms better than commercial fertilizers. Spend more money and effort on improving the soil than buying and applying specialty fertilizers. Improving the soil and using organic surface mulches around non-desert plants reduces the need for chemical soil amendments, fertilizer applications and pesticides. Called a starter fertilizer because it is high in phosphorus, the middle number. Excellent fertilizer when planting for the first time or seeding in the garden. You can mimic this fertilizer and save a little bit of money but is it worth it? With proper soil improvement, here are my recommendations for fertilizer applications, either conventional or organic: · nitrogen and potassium is needed by all plants on a regular basis · apply phosphorous fertilizers when planting: seed, transplants from containers or bare root, rhizomes, bulbs or any plant just getting started · plants grown for their flowers or fruit require at least one fertilizer application of nitrogen plus phosphorus during the growing season and applied 2 weeks before flowering and fruiting · fertilize vegetables and annual flowers monthly; lawns every 8 weeks · fertilize prized landscape plants more often than “ordinary” landscape plants · use specialty fertilizers on rare occasions for very specific reasons

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Are Pears with Corky Spot Edible?

Leave a Comment / brown spot, corky spot, pear disease / xtremehorticulture

Q. I was reading your blog about the brown spots in the flesh of pears. Is fruit with these spots edible? Keiffer pear with outside evidence of Corky spot With the small green dimple in the center of the fruit A. Corky spot in pears appears as brown areas, about the size of a small marble or smaller, in the flesh of the fruit. These spots are surrounded by healthy flesh. On the outside skin it is hard to see but often it is slightly sunken and frequently some green remains after the fruit ripens. The flesh is not rotten. The cells in the flesh do not have enough calcium for good development and they die and are brown. These spots do not taste good and are usually dry. But if you eat them it’s not a problem and will not harm you. Corky spot on the interior flesh of Keiffer pear. My experience with this “disease” is that it develops on pears grown on older trees, usually over ten years of age. I theorize that the roots of the tree have exhausted the calcium in the soil surrounding them. The soil is full of calcium, but it cannot release it fast enough as the fruit develop. Corky spot on Comice pear growing in the Mojave Desert What to do? Applications of calcium to the soil are not 100% effective. It is recommended that the fruit on the tree is sprayed with a liquid calcium solution as the fruit is enlarging. The most effective sprays are made with 5% calcium chloride dissolved in water. The calcium chloride should be food grade. 5% solution of Foodgrade calcium chloride will work as a foliar spray. This foodgrade calcium chloride is for homebrewing These spray applications are made five times, at least a week apart, as the fruit enlarges. Direct the sprays mostly at the fruit. Leaf sprays are less important. Not all pears are affected equally. Some pears appear to handle low soil calcium levels better than others. The problem may also vary with different types of soils. Watch for it on older pear trees. By the way, this disorder also affects some apples. When it does, it is no longer called “Corky Spot” but “Bitter Pit” instead.

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Mojave Desert Six Pines Available

Leave a Comment / Desert Pines, Pines for the Mojave Desert / xtremehorticulture

Q. I want to plant pine trees like I saw at the Hughes Center near Sands and Paradise. They have foliage near the ends of the branches and have a round shape rather than conical or a Christmas tree shape but I don’t know what they are. Elderica or Mondel pine With its Christmas tree like shape A. They might be attractive when they’re small, but most pine trees are large when mature, don’t fit in small to medium-sized landscapes and are not compatible (design-wise) with one to two-story homes. They might be fine for commercial landscapes and parks but not around homes on small residential lots in the desert. Aleppo pine in its youth I think the trees you saw were still relatively young, 20 years or less, planted too close together and not given enough water. This is why they were round in shape with needles only at the ends of the branches. Pine tree availability at nurseries is somewhat limited compared to other parts of the country. I believe the pine tree you saw that interests you is an older Mondel or Afghan pine which becomes rounded as it matures and attains a height of 40+ feet. Aleppo pine at maturity near parking lot Another commonly sold pine here is Aleppo which resembles Mondel pine in its youth. Both trees when younger are pyramidal or Christmas tree-like in shape. Mondel becomes more rounded with age and Aleppo pine becomes “gangly” and informal in shape. Aleppo pine can reach heights of 60 to 70 feet. Japanese black pine with its very distinctive silhouette A third large pine planted here in the 1980s and making a comeback now is Chir or long-needled pine. It is a very graceful, pyramidal pine less tolerant of cold winter temperatures. All three of these large pine trees should not be used in small residential landscapes particularly with single-story homes. Chir pine Which used to be called Pinus longifolia and you can see why because of its long needles. This pine tree fell out of disfavor during extremely cold winter where many of them were severely damaged or outright killed. It’s making a comeback and a beautiful distinctive pine. So-called “smaller pines” may not actually be smaller when mature. Italian stone pine, a pine tree with a rounded shape all through its life, is a slow growing pine that may be acceptable in smaller residential landscapes for a number of years. However, it can reach 50 feet when mature. It can also provide edible pine nuts, the chef’s pignoli. Picture of stone pine Our state tree, single leaf pinion pine, would be a good choice for desert landscapes if you could find it. But it to can be large as well, 50 feet or more, when irrigated and given time. It also produces edible pine nuts. Picture of pinion pine A pine tree popular with landscapers and architects over the years is the very distinctive Japanese black pine. It has been touted to be tolerant of alkaline soil but is a “specimen” pine with a unique shape that makes it popular in “designer landscapes”. However, I have never seen a Japanese black pine perform well here in our climate and soils. You see it used further north in arid states. further north in aired states You don’t find many older ones around town which may speak volumes about how well it is suited for our location.

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Fruit Tree Leaves Okay on the Ground, Fruit Not

1 Comment / confused sap beetle, dried fruit beetle, Harvest and post harvest pests / xtremehorticulture

Q. We have fruit trees planted in an area we have covered with wood mulch. We always clean up the fallen fruit. Can we leave the fallen leaves on the ground or do they need to be cleaned up? Western Box Elder bug ready to feed on dried apple still hanging on the tree, pecked by a bird. This insect feeds on decaying plant material but if it can get inside an old fruit through a bird peck, it will. A. It is always a good idea to clean up fallen fruit because of pest problems. It is also very important to remove dead fruit from trees after harvesting. I like to see fruit picked up from the orchard floor at least weekly. If you don’t, it can lead to numerous insect and vertebrate pest problems. If you are composting this fruit, either bury it in the compost pile or put it in a sealed containers where pests can’t get to them. This is a picture of the confused sap beetle on the University of California IPM website. Very common pest found in orchards where the old fruit is left on the ground or hanging on the trees. The simple control measure? Pick up fallen fruit from the orchard floor and dispose of it right away. http://ipm.ucanr.edu/PMG/r261300111.html One common insect problem with nearly all soft fruit when it’s ripe are fruit beetles. They get into decaying fruit on the orchard floor where their populations multiply rapidly. These beetles then infest soft mature fruit hanging on the tree waiting to become “tree ripened” or disposed fruit laying on top of the compost pile. Picture of a pest of old fruit left on the ground or not removed from the trees, the dried fruit beetle. How to get them under control? Sanitation. Pick up fallen fruit and remove old fruit from trees. Fig fruit in particular is a big source of this problem. http://ipm.ucanr.edu/PMG/r261300111.html If this is a problem with your fruit trees, improve orchard sanitation by picking up fallen fruit and remove old and damaged fruit hanging from the trees. An entry point for dried fruit beetle inside figs is the “eye” or hole at the bottom. Some figs have closed “eyes” and others are open. These rascals like the open ones so they can climb inside and cause havoc. Leaves from most fruit trees are not a problem if left on the ground to decompose. That’s not true however in the vegetable garden and possibly other parts of the landscape. Leaves and stems will decompose much faster if they are chopped or shredded first. If it were me, I would shred leaves and stems and leave them on the orchard floor to decompose but not the fruit.

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Think Twice Before Purchasing Timber Bamboo for a Residence

Leave a Comment / Caring for timber bamboo, Desert climate / xtremehorticulture

Q. A local nursery has timber bamboo available-for-sale. How far from a brick wall should they be? How far apart should they be? Should they go on a planter box? Do I need a barrier for the roots? Timber bamboo at a residence kept under control A. I have giant timber bamboo growing on our family farm in the Philippines. They grow close to a small stream of water bordering our large farm property. In the tropics, they are quite useful for construction. I am less enthusiastic about them for smaller residential properties. I am even less enthusiastic about them for the desert. Put them in parks or large commercial properties where water is cheap. Bamboo is probably the most utilized plant for different construction purposes in the world. It is highly versatile. You need lots of room to grow timber bamboo. Bamboo is in two basic categories; clumping and running. Most of the cold weather bamboo are running which means they spread underground several feet before they pop out. Clumping bamboo has very short underground rhizomes so they pop out very close to the mother plant. Clumping bamboo is preferred for residential properties. Timber bamboo is clumping. But hold on. Timber bamboo is massive and extremely powerful. It will heave walls, driveways, patios easily. They require very large amounts of water that’s why ours grows next to a small stream. Timber bamboo planted in Las Vegas Nevada near the back wall of an apartment property. I took this shot several years ago. It is probably gone because of destruction to the wall and the parking lot. It should not be planted in small spaces. Timber bamboo comes in several species and there are some very cold hardy ones that can easily handle our winter temperatures. That is not what I’m concerned about. I am concerned about how aggressive they are. In the tropics they can grow to seventy or 80 feet tall. In the desert they will be considerably shorter because of the low humidity, high temperatures and lack of available water unless you are flooding them. These plants will become a nuisance in about 3 to 4 years after planting. You will have to stay on top of them and remove suckers and keep the underground rhizomes in check. I would not use them in the desert. If you decide to plant them, I would give at least a 5 foot “no grow” area surrounding them. This means you should remove “suckers” coming from the rhizomes that pop up in this area. That will help to control it spread somewhat. Close-up of the same plant and you can see how it spreading underground by short rhizomes producing “culms” or suckers. I would plant them no closer than 15 feet apart and expect them to grow to 40 feet in height. The clumps will grow larger in diameter over the years. Sometimes called heavenly bamboo, it is not even closely related to bamboo. This is Nandina domestica poorly managed. You will not control them with shallow root barriers. Use root barriers are at least 2 feet deep. Their roots and rhizomes are shallow but a 1 foot deep root barrier will not be enough to keep them contained. Install root barriers after three or four years. An option is to trench around the clump every 2 to 3 years, cut the rhizomes and remove them. Expect to increase your budget for water.If given enough water, they are extremely fast growers.

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Controlling Corky Spot on Pear at a Second Home

Leave a Comment / Brown spot on pear, Calcium deficiency / xtremehorticulture

Q. What if I can’t do 5 consecutive weekly sprays to control brown (corky) spot on pear? My problem Kiefer pear is at a second home and I am not usually there that long at a time. A. Five sprays at least one week apart as the fruit is enlarging is recommended. Get as many applications on as you can, at LEAST a few days apart, as the fruit is enlarging. Use food grade calcium chloride and not deicing salt or salt used in water softeners. You are going to eat this. If you can’t be there when the fruit is enlarging, then it will be a problem. You cannot spray the fruit after it is large or when it is very small and expect to correct the problem. Try substituting calcium fertilizers such as calcium nitrate during your Spring application of fertilizer. You might try applying gypsum to the soil in spring since it also contains calcium. Organic approaches would be to apply organic labeled gypsum, shells, dolomite and marl. These sources of calcium must be very finely ground, like flour, to be effective the same year it’s applied.

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Pahrump Fruit Tree Selection Similar to Kingman and St. George

Leave a Comment / Arizona, cold air drainage, fruit tree selection, Utah, windbreaks / xtremehorticulture

Q. We recently moved to Pahrump. Nevada, What recommendations would you give for fruit bearing plants other than pomegranate and fig? We get some cold nights in Jan and Feb. I posted this climate information from the Internet for Pahrump, Nevada, USA. I was disappointed. The weather can get much colder than this in the winter (down to 10F easily) and hotter in the summer 110F plus. Its saving grace is its elevation which makes it colder than Las Vegas 75 miles away. Plus it does not give much information on the wind which can be brutal during low temperatures and high temperatures. It is on the doorstep to Death Valley. A. For sure apples and pears, most of the plums will be fine. Take a look at the possibility of sweet and tart cherries and apricots. Although your weather might be too dry for a good fruit set. There is an active gardening group in Pahrump with many of the active with Cooperative Extension horticulture there https://www.facebook.com/Pahrump-Master-Gardeners-420253654687416/ Contact them for more specific advice. They have an active Farmers Market during growing times of year https://www.facebook.com/PahrumpFarmersMarket/ You should relate closely to…gardeningwise…. Kingman, Aarizona, and St. George, Utah, as well. Both cities have active gardening groups closely tied to their respective Cooperative Extension offices in Kingman and St. George. Fruit trees that flower earliest should be planted on slopes. Fruit trees that flower later can be planted in the lower elevations. Remember microclimates and cold air drainage can be a game changer. I can make general recommendations for that climate but it varies even more with your local microclimate. There will be colder areas and warmer areas in the valley due to wind and cold air drainage. Cold air is like water…it drains to low spots. Low areas will have late frosts in the spring and early frosts in the fall. In those areas season extenders such as low and high tunnels aka greenhouses without heaters or cooling pads…would be advised. Select fruit trees in these areas that delay their flowering in the spring as much as possible. The area protected on the leeward side of a windbreak can be divided into three sections designated here as A, B and C. The area a closest to the windbreak has wind of modified the most, a short distance equal to about 1 to 2 times the height of the windbreak. Area B is modified but less; up to about five times the height of the windbreak. And the sea is modified even less up to about eight times the height of the windbreak. This is why windbreaks should be planted close to the area needing protection. Consider windbreaks to protect the gardening areas. These windbreaks should be very close to your planted area and NOT planting tall trees along the perimeter of the property as so many people hsve done out there. Its a waste of water. The wind is broken up to a distance of about five to eight times its height. Big trees require more water so planting on the perimeter uses alot of water and you get very little benefit from them. To me it looks like a prison, although prettier than fencing.

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Frost Blanket, Crop Cover, Floating Crop Cover

Leave a Comment / Uncategorized / xtremehorticulture

Q. You wrote about some kind of blanket to wrap your plants with when it gets cold in winter to keep frost harming them. Can you tell me where I can buy them? When these covers are used to protect from freezing weather, they’re called frost blankets. A. Frost blankets don’t produce any heat. They capture heat radiated from the soil or other surfaces that are warmed by the sun and also protects plants from wind. Wind is a partner in winter damage because warmth radiated from the ground, a nearby wall or even from the trunk of the plant itself, is lost quickly if there is air movement pushing it away from its source. Sometimes crop covers are stretched over hoops to make low tunnels. Depending on their use, sometimes they are called floating row crop covers, crop covers, row crop covers. They are pretty much the same but another tool in the “toolbox” for gardeners. These fabric covers permit air and moisture to move through them but trap heat and disperse high light intensities. Some people use plastic sheeting or blankets to protect the plants from frost damage. They act like wind barriers and insulation. But frost blankets trap enough heat to keep crops 4 to 5°F warmer during light freezes. Frost blankets are lightweight, don’t have to be washed and are reusable. A difference in germination and seedling growth when a crop cover is used on the right versus no crop cover used on the left. I have used frost blankets to cover broccoli, cauliflower and cabbage during cold winter months if I thought the temperatures were going to drop dropped really low. These blankets are rolled on top of plants, stretched over hoops and pinned to the soil so they don’t blow away. If left on during cool, overcast days they push growth more than leaving plants exposed to the elements. Use them during cool weather, not when temperatures are hot. They work really well if a few degrees of protection is needed. But if temperatures get too low. they won’t provide enough protection. Use I use them for insurance against moderately low temperatures that might cause damaged plants or when you want to push a little bit of growth during cold weather. They are available at local nurseries and garden centers as well as online stores. Two manufacturers of these frost blankets that come to mind are DeWitt and Agribon. Try GrowOrganic.com, Johnny’s Seeds, Greenhouse Megastore, Amazon, Park Seed Company, Harris Seeds and other online vendors. Please also check your local nursery. Many of them carry it.

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Pomegranate Fruit Splitting Usually Water Problem

Leave a Comment / Uncategorized / xtremehorticulture

Q. I have grown Utah Sweet pomegranates in Summerlin for several years and only had a few fruit split open near the Fall harvest time. Mid July this year 40 green fruits split open. I assumed it was from high temperatures but more kept splitting open through the rest of the year. At least 80% of the fruit have split open and the birds cleaned out all the edible seeds. Split Utah Sweet pomegranates do to watering problems. A. Harvest times for pomegranates are at different times depending on the variety of pomegranate. The earliest varieties start ripening in September and other varieties extend the harvest season past Halloween. The usual reason for early fruit splitting is irregular applications of water: soils alternating between wet and dry. Pomegranates handle high temperatures easily but they don’t produce well if water in the soil is limited during its fruiting cycle. Split Utah Sweet pomegranates most likely from irregular soil moisture. This can be a particular problem when trees are on drip irrigation and surrounded by dry soil. Don’t turn off the irrigation system when it rains when growing in the desert. The amount of water the plant received is hard to calculate. Fruit splitting is a watering issue, not a temperature issue but the two could be related. If water is not available when the fruit is increasing in size, even for a day or two, fruit will be smaller because they begin maturing too early. Their outer “skin” begins to harden early. Now it rains heavily. This abundance of water available to the roots is “pushed into the fruit causing the fruit to expand and split. Unusually high temperature, combined with wind and an unprotected soil surface, can cause drought at times that are unexpected. Irrigation water is supplied according to a clock but it is too late. The damage is done. Put a surface layer of mulch 3 to 4 inches deep on top of the soil to slow water evaporation from the soil surrounding the roots. This surface layer of mulch helps to reduce wildly fluctuating amounts of water in the soil when it is hot and windy. Pomegranate before winter pruning and surrounded by wood chip mulch in the desert Use woodchips from trees pruned by local arborists. Extend this surface layer of mulch so that it completely covers the soil under the tree canopy to a depth of four inches. Make sure these trees receive enough by adding emitters as it gets bigger and checking the soil moisture during hot weather. Round hole in the side of pomegranate with inside totally cleaned out is a pretty good indicator of a rat problem. Birds eat pomegranate seed after the fruit has split open. They can’t open pomegranate fruit by themselves. Rats gnaw on the outer “rind” of the fruit leaving a large, somewhat round gaping hole in the side of the fruit with the inside totally cleaned out. One of the pictures you sent to me looks more like rat feeding than bird damage. Because rain in the desert happens so infrequently, never use the rain shut off on the controller. Irrigate plants even though it rained because estimating the amount of rain plants receive is very difficult to do accurately.

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