Xtremehorticulture

Xtremehorticulture of the Desert

Winter Cold Damage and Freezes

Leave a Comment / did it freeze, freezing plants, freezing weather /

Oleander after a strong freeze. This is the time of year, the second week of December, we normally experience the start of freezing temperatures. The likelihood of freezing temperatures increase through the winter. Sometimes freezing temperatures occur in November, as it did a few years ago, but that’s rare and not “normal”. What I mean by “freezing temperatures” is plant damage that occurs anytime the air temperature drops below 32 degrees Fahrenheit (F). Those familiar with Celsius or centigrade, may realize this temperature is the same as 0 degrees on the Celsius scale. Cold or freezing damage. Refrigerators Don’t Freeze As a reference point, the temperature inside most refrigerators is set to around 40 degrees F, or 8 to 10 degrees above freezing; too cold for most tropical fruit and plants but not too cold for temperate fruit like and plants apples and peaches. Chilling injury (plant damage that occurs because air temperatures are too cold for the plant but not yet freezing) is one reason many ripe tropical fruits, like tomatoes and (more obviously) bananas, should not be exposed to the 40-degree F temperatures of a refrigerator.  If winter temperatures aren’t cold enough to kill, the plant will regrow from buds. Chilling Injury All parts of tropical plants such as tomatoes and bougainvillea, experience “chilling injury” when temperatures drop a few degrees above freezing and may extend to 50+ degrees F. Chilling injury (as opposed to freeze or frost damage) occurs at different temperatures and depends on the plant. Tomato plants might freeze at 32F but the fruit is damaged below 55F. Chilling injury damage to tropical and subtropical plants include small stem and leaf discoloration, leaf roll, poor growth, and susceptibility to some diseases like root or collar rot. Symptoms of chilling injury include a change in color such as yellowing or bronzing of leaves that ultimately result in leaf scorch or drop, the slowing or halting of growth, leaf drop, water-soaked patches in soft and semi-hard tissues, susceptibility to diseases, and wilting. Chilling injury is due to cooler or cold weather (above freezing) temperatures to tropical plants growing outside of, or close to, the fringes of their normal range. As a side note, I noticed leaf and stem discoloration (closer in color to leaf “bronzing”) in mesquite, palms, citrus and a wide range of plants growing at different temperature ranges. Chilling Injury and Vegetables Vegetables can exhibit chilling injury and freezing damage as well. So-called “warm season vegetables” such as tomatoes, peppers and eggplant can show chilling injury anytime the air temperature drops into the damaging temperature range I mentioned earlier. Cool season vegetables, on the other hand, may sail through the same temperatures, or lower, or require a crop cover when temperatures are below freezing. Vegetable varieties may differ in their chilling injury by a few degrees. The ‘Dragon’s Tongue’ variety of bush bean is more susceptible to collar rot (chilling injury) when grown in garden soil a few degrees cooler than other bush bean varieties. Nopales freeze damage during the winter of 2007-2008 Temperate Flowers and Fruit Can Freeze Temperate fruit like apples and pomegranates, unlike tropical fruit like tomatoes and bananas, are not damaged at refrigerator temperatures (around 40 degrees) because fruit from these trees can handle these lower temperatures. The ideal storage temperature for these types of fruit is somewhere close to freezing (0 degrees F) and combined with high humidity. A high humidity slows water loss and helps delay some fruit from shriveling. Refrigerator Freezers and Freezing The freezer part of our refrigerator is set to around 32 degrees F, or about 10 degrees below the “refrigerator temperature.” Our nighttime winter temperature frequently drops to a “refrigerator temperature” range at night during the late fall, winter and early spring and occasionally into the “freezer temperature” range during the early morning hours of December, January and occasionally early February. When nighttime temperatures reach the “freezer range” is when we often times see plant damage or experience fruit loss, but we may not know it yet. Open Flowers can Freeze Open flowers of any fruit (citrus, peach, apple and others) can’t handle temperatures below freezing (32 degrees F) even though most plants or trees might show no damage at all! When flowers are simply buds and not yet open, there is a small amount of freeze protection provided to the developing flower. This freeze protection starts disappearing as the flower buds mature into open flowers. As the flower begins opening, and the frost-sensitive ovary is surrounded by the freezing night air, is when we experience damage or fruit loss. Fruit loss due to a frozen flower ovary can happen in a few seconds. This is why sprinklers, ultimately resulting in applied water turning to ice on the flowers, are used in orchards to prevent freeze damage to flowers (ovary). The act of water freezing releases a small amount of heat that protect flower ovaries from death. Early winter freeze damage to persimmons. Was the Flower Frozen? If you are curious if the ovary of a flower from your fruit tree was damaged during a freeze, pull the flower apart a few days after a suspected freeze and inspect the ovary for death. Ovaries that eventually turn into fruit will be robust and green. Dead flowers drop from the tree early or have a dull, water-soaked appearance if they are still attached. Just because the flower you inspected was “dead” doesn’t mean there will be no fruit produced at all. It takes about two or three weeks for all the flowers to open in spring flowering plants. Several consecutive light freezes in a row (or only one hard freeze) are needed to totally wipe out a crop of fruit from a mature tree. when a fruit tree flowers it is hold your breath that no freezes happen during this time. When fruit tree flowers are open is a dangerous time for freezing temperatures. Freezing Death Differs  There is a temperature difference between the freezing

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Pines in Logandale Need Less Fertilizer But the Same Amount of Water

Leave a Comment / fertilizer, Logandale, pine trees, water /

In my experience trees like Aleppo pine need fertilizer applied AT THE MOST once a year and perhaps less often.  Non-Flowering and Non-Fruiting Trees Need Mostly Nitrogen and Potassium In the case of pine trees mostly nitrogen and potassium because we don’t need them to flower or fruit. That requires fertilizer higher in phosphorus, the middle number. Whenever the trees are “improved” (hybridized or improved for some reason) they need to be fertilized more often and need more care. For example, most fruit trees require one full or a split application of fertilizer twice a year. Force Them After this Water My guess is that your pine trees, at the most, will need fertilizer applied once a year in the spring. Improved trees like fruit trees need about one pound of a nitrogen fertilizer in the spring (or the fertilizer divided in half and applied twice) for each 1000 square feet under their canopy. Aleppo pine trees require it less often or apply less total amount each time you fertilize. Look at the results of irrigations and applications of fertilizer. The fertilizer is needed every year or every other year. A tree of that size should put on about 8 inches of new growth every year to keep it full. That takes primarily nitrogen similar to a lawn fertilizer (21-7-14). Don’t skimp on nitrogen and potassium in the fertilizer for pine trees. Because they are “all green” and no flowers or fruit you can apply less of the middle number (the amount of phosphorus). As far as applying irrigation less often or eliminating them, you need shallow groundwater to about 5 to 7 feet deep. At the same time force its roots to grow deeper in the soil so it can discover the water. Pine trees have taproots or large roots that can grow deep if given the chance. Groundwater can go down in the summer months and up to normal in the winter. What I am telling you is that you might need to water occasionally during the summer months. When you irrigate, water the trees deep when you do, water them less often and watch the tops. Force the tree roots “to go after” deeper water and see how much fewer extra irrigations they need and still maintain 8 inches of new growth during the early summer months.

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Bitter Orange in Las Vegas

Leave a Comment / bitter orange, trifoliate orange /

Q. I was so happy to see an article you recently wrote in the RJ concerning bitter orange trees.  I have one that was here when I bought my house 16 years ago.  It was in a patio pot at that time and I had it replanted, along with a Meyer Lemon, in the “alley” between my house and my neighbor. Bitter orange tree planted in Las Vegas. My lemon has been giving me fruit for the past approximately 8 years and about 30-35 lemons.  My orange tree has always produced flowers, but no fruit up until 2 years ago. I got about 25 nice sized oranges.  Last year I got flowers but Not A SINGLE fruit. Is this a tree that may “skip” a year in fruit production?  I have done nothing to these trees except fertilize with Arizona Best’s Citrus fertilizer Valentine’s Day, Memorial Day and Labor Day. Myers lemon (not readers) planted in Las Vegas. A. “Skipping” a year is called “alternate bearing” and occurs, usually, with older varieties of fruit trees like some almonds and apricots. Bitter orange, like most oranges, produces the majority of its flowers in the early spring. This is the same time we experience freezing weather. Your fruit loss could be because of freezes. Did You See Flowers? It is important to ask, “Are you sure you saw flowers in the spring and no fruit?” That’s an important consideration. If you did then it was a failure to set fruit. That is either because no pollinators were present (bees and other pollinators like flies and moths) or it froze several times in a row in the early spring. No Flowers If you did not see flowers in the spring, then it was because it never flowered. That could be because of some hard pruning that was done, and the tree is recovering, or too much fertilizer was applied too often. This is true particularly of high doses of nitrogen fertilizer such as ammonium sulfate (21-0-0). In either case, the tree grew so vigorously that it never flowered! Fertilizer Applications Normally one fertilizer application is all that is necessary, or two at the most. If two is applied, then apply half of your normal fertilizer application in the early spring and half right after harvest. If harvest is close to your early spring application time then apply fertilizer to citrus just before it gets hot in the early summer. Avoid making fertilizer applications when it is hot. In the case of citrus that might freeze, avoid fertilizer applications after July. Tree Surrounded by Rock Mulch Some citrus okay with rock mulch. I noticed that the tree is surrounded by rock mulch. Yet it has good color. Citrus of all types don’t usually like rock mulch all that much. The first thing to go is dark  to medium green color in the leaves when it gets unhealthy. That’s why I was surprised with your tree. Maybe your choice of fertilizer helps. Some citrus not okay with rock mulch. Use amended soil when planting and citrus fertilizer every year. Citrus are from southeast Asia and China. They prefer to grow in soils with a higher organic content than most soils covered in rock. Along with your fertilizer application try raking back the rock at least three feet all around the tree and applying compost or wood chips to the top of the soil. Water it in and rake the rock back on top of it after it is watered. Do this about every year or every other year at the least. I think your bitter orange will like this type of soil better than soil covered in rock. Pomello on our farm in the Philippines.

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Properly Staking Trees and Other Plants in Desert Soil

Leave a Comment / girdle, wires staking /

 Q. I have a tree that was staked and now the wires used in staking it are starting to strangle the tree trunk. Fairly common forgetfulness of homeowners and plant maintenance companies. Tree staking. Proper staking removes the stakes after one season of growth. A. That’s a common problem on large, staked trees planted in home landscapes. It’s a gamble on the wind whether to stake or not to stake. I encourage people to stake nearly all plants. It’s cheap insurance. On smaller 5-gallon plants (sometimes even 15-gallon shrubs) the small, square, green nursery stake found in the container may be adequate if cut loose from the plant, driven or pushed into the moist, solid ground beneath the plant. Retie the plant when you’re finished. Always have some half-inch, stretchable green nursery tape on hand. It’s very useful. Green stretchable nursery tape is used to tie one inch caliper bare root trees to a wooden stake. The purpose of staking any plant is to keep new roots from being damaged during establishment. The movement of roots usually happens during strong winds. Planting in wet planting holes and amending the backfilled desert soil may get around the use of stakes with smaller plants. Use your judgement. Wind blew over this cactus either because it was watered too often, watered too close to its center. If the soil surrounding the roots were moist, this cactus would find water further from its center and resist blow over. Typically staking is only needed for one growing season and then removed. One growing season is all that is needed to establish plant roots in the surrounding soil and make the plant secure against wind.  Some homeowners may think the reason for staking is to hold the tree upright. That’s only partially true. On occasion more than one growing season of staking may be needed when planting trees grown too close to each other in wholesale or production nurseries. In cases like these, metal ties are loosened and then retightened at the end of each growing season to prevent “choking the trunk” as seen in your picture. Remember, plants grow in two dimensions; length AND girth. Sometimes excessively tall and weak plants must be pruned smaller to encourage new, stronger growth.  The proper way to stake a tree is to allow the canopy and trunk of the tree to move but not it’s roots. Movement of a tree’s trunk allows it to gain taper (become stronger) as it grows in size. Trunk taper may or may not be missing because of production nursery practices. Properly grown trees have a tapered trunk as you look at it from top to bottom.

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Some Plants are Damaged if Temperatures are Above Freezing

Leave a Comment / chilling damage, freeze damage, fruit, tomatoes, tropical plants /

Some plants can get damaged at temperatures above freezing. Learn how and which ones. Chilling damage occurs mostly to tropical fruit if temperatures are like a refrigerator. Freezing Temperatures This is the time of year, the second week of December, we normally experience the start of freezing temperatures. The likelihood of freezing temperatures increase through the winter. Sometimes freezing temperatures occur in November, as it did a few years ago, but that’s rare and not “normal”. What I mean by “freezing temperatures” is plant damage that occurs anytime the air temperature drops below 32 degrees Fahrenheit (F). Those familiar with Celsius or centigrade, may realize this temperature is the same as 0 degrees on the Celsius scale. What is Chilling Injury? As a reference point, the temperature inside most refrigerators is set to around 40 degrees F, or 8 to 10 degrees above freezing; too cold for most tropical fruit and plants but not too cold for temperate fruit like apples and peaches. Chilling injury (plant damage that occurs because air temperatures are too cold for the plant but not yet freezing) is one reason many ripe tropical fruits, like tomatoes and (more obviously) bananas, should not be exposed to the 40-degree F temperatures of a refrigerator. All parts of tropical plants such as tomatoes and bougainvillea, experience “chilling injury” when temperatures drop a few degrees above freezing and may extend to 50+ degrees F. Chilling injury (as opposed to freeze or frost damage) occurs at different temperatures and depends on the plant. Chilling Damage Chilling injury damage to tropical and subtropical plants include small stem and leaf discoloration, leaf roll, poor growth, and susceptibility to some diseases like root or collar rot. Symptoms of chilling injury include a change in color such as yellowing or bronzing of leaves that ultimately result in leaf scorch or drop, the slowing or halting of growth, leaf drop, water-soaked patches in soft and semi-hard tissues, susceptibility to diseases, and wilting. Chilling injury is due to cooler or cold weather (above freezing) temperatures to tropical plants growing outside of, or close to, the fringes of their normal range. As a side note, I noticed leaf and stem discoloration (closer in color to leaf “bronzing”) in mesquite, palms, citrus and a wide range of plants growing at different temperature ranges. Warm Season Vegetables Usually Have More Chilling Damage Vegetables can exhibit chilling injury and freezing damage as well. So-called “warm season vegetables” such as tomatoes, peppers and eggplant can show chilling injury anytime the air temperature drops into the damaging temperature range I mentioned earlier. Cool season vegetables, on the other hand, may sail through the same temperatures, or lower, or require a crop cover when temperatures are below freezing. Vegetable varieties may differ in their chilling injury by a few degrees. The ‘Dragon’s Tongue’ variety of bush bean is more susceptible to collar rot (chilling injury) when grown in garden soil a few degrees cooler than other bush bean varieties. Refrigerator Temperatures Result in Chilling Damage Temperate fruit like apples and pomegranates, unlike tropical fruit like tomatoes and bananas, are not damaged at refrigerator temperatures (around 40 degrees) because fruit from these trees can handle these lower temperatures. The ideal storage temperature for these types of fruit is somewhere close to freezing (0 degrees F) and combined with high humidity. A high humidity slows water loss and helps delay some fruit from shriveling. Freezer Temperatures Result in Freezing Damage The freezer part of our refrigerator is set to around 32 degrees F, or about 10 degrees below the “refrigerator temperature.” Our nighttime winter temperature frequently drops to a “refrigerator temperature” range at night during the late fall, winter and early spring and occasionally into the “freezer temperature” range during the early morning hours of December, January and occasionally early February. When nighttime temperatures reach the “freezer range” is when we often times see plant damage or experience fruit loss, but we may not know it yet. Open Flowers are All Subject to Some Type of Damage Open flowers of any fruit (citrus, peach, apple and others) can’t handle temperatures below freezing (32 degrees F) even though most plants or trees might show no damage at all! When flowers are simply buds and not yet open, there is a small amount of freeze protection provided to the developing flower. This freeze protection starts disappearing as the flower buds mature into open flowers. As the flower begins opening, and the frost-sensitive ovary is surrounded by the freezing night air, is when we experience damage or fruit loss. Fruit loss due to a frozen flower ovary can happen in a few seconds. This is why sprinklers, ultimately resulting in applied water turning to ice on the flowers, are used in orchards to prevent freeze damage to flowers (ovary). The act of water freezing releases a small amount of heat that protect flower ovaries from death. If you are curious if the ovary of a flower from your fruit tree was damaged during a freeze, pull the flower apart a few days after a suspected freeze and inspect the ovary for death. Ovaries that eventually turn into fruit will be robust and green. Dead flowers drop from the tree early or have a dull, water-soaked appearance if they are still attached. Just because the flower you inspected was “dead” doesn’t mean there will be no fruit produced at all. It takes about two or three weeks for all the flowers to open in spring flowering plants. Several consecutive light freezes in a row (or only one hard freeze) are needed to totally wipe out a crop of fruit from a mature tree.  There is a temperature difference between the freezing death of open flowers and the freezing damage or death of the plant or tree. For citrus this difference can range from the same temperature as flower death (32 degrees F; limes and true lemons) to lower temperatures (mid 20 degrees F; Myer lemon, grapefruit, and kumquat).

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Yellow Leaves on Potted Myer Lemon

Leave a Comment / fruit trees, lemon, Light, watering /

Q.  I have a Myers lemon tree in a pot on a south facing patio. The wall near it faces east and there was a large pine tree out front so it receives shade in the afternoon. There are quite a few yellow leaves that just appeared. All the new fruit has turned black. It seems to me that maybe I just need to replace this tree. The lime tree is doing very well in a similar location. A. The picture you sent to me shows a Myer lemon with ready to harvest fruit being grown in a small container with smaller plants growing around its base. Meyer lemon typically flowers sometime in January and February. The fruit can be harvested starting about now (December) with this harvest, finished by January, encourages new flower development for next year’s production. Producing flowers and then fruit in midfall is early for Meyer lemon. Early flower development can be a sign that it is under some sort of stress. Certainly it’s not normal for this type of tree at this time of year.             All fruit trees and vegetables need a minimum of six hours of full direct sunlight. 8 hours is even better. In home landscapes the best sunlight for it in our hot climate in the summer months is during the cooler morning hours. Partial shade may be pleasant for people sitting on the patio but not for many plants that produce fruit or vegetables. If shade is present during most sunlight hours, then I would recommend an ornamental plant for that spot with variegated or colorful leaves, not a flowering or a fruit-producing plant. A non-flowering ornamental handles shade better than a flowering plant, whether those flowers produce fruit or not. Don’t Plant Annuals at the Base of Perennial Trees             Secondly, and perhaps more importantly, are the smaller plants demand for frequent watering compared to the tree. Growing a shallow-rooted plant or plants at the base of a deeper-rooted plant is a big “no-no” regarding how often water is applied. Shallow-rooted plants “signal” they need water applied more often than deeper-rooted plants, so they get water applied more often than the watering frequency needed for deeper-rooted plant needs. This type of watering can suffocate the roots of a deeper-rooted plant. Watering a deeper-rooted plant too often can produce leaf drop, flower drop, fruit blackening, and a tree that’s “loose in the soil”. Trees that develop “collar rot disease need to be staked after just a few years of growth. Does that sound like your fruit tree?             I would replace this tree with a plant that requires moderate to low levels of sunlight. If you want to grow other plants along with it, select plants with a similar rooting depth and need for applied water.

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Pecans With Black Spots and Bitter Meat in Southern Nevada

Leave a Comment / black spots, meat, off taste, pecan, scab, venturia /

Q. I had two pecan trees that are now 25 years old. One variety has round nuts and the other one has oblong nuts. This is the first year in 25 years they have produced nuts that have black spots and are bitter tasting but the outside of the nut looks normal. Any idea what the problem might be? Pecan scab. Picture from Texas A and M University. A. Pecan nut problems are hard to diagnose. The nuts themselves can be bitter if some of the husk is attached to the nut. But yours sounds like a disease issue to me. Perhaps it was our wet early summer and spring that created the problem. The most common disease of pecans is scab. When it is a wet spring, after a rain, it is wise to spray the trees in March with a fungicide such as Bordeaux or copper sulfate. If it rains again, spray it again after the rain has stopped. The problem is spraying these trees top to bottom since there are no systemic fungicides that can be applied to the soil and taken up by the roots. The lesions on the outside surface of the shell this disease produces are difficult to see and does produce an “off flavor” once inside the meat. I must guess a little bit, but the varieties popular about 25 years ago in the West were oblong nut varieties called “Western Schley”, “Mahan”, “Wichita”, “Mohawk”, and “Cheyenne”. The older and round nut varieties were either “Burkett” or possibly “Choctaw”. The reason I mention it is because there are probably well over a hundred varieties of pecan. The more recent hybrids are smaller, produce nuts sooner, less likely to bear nuts every other year (alternate bearing), and don’t need a pollinator tree. Also “Choctaw” and “Cheyenne” varieties were considered “resistant “to this disease. Even though pecan trees can handle our summer heat and poor soils, I don’t recommend them for our area because of their size and water use. Pecan trees can get big, growing 60 to 100 feet tall and 30 to 50 feet wide, and have no semi-dwarf or dwarf varieties that I know. Their size dictate they use a lot of water. They do have a sizeable tap root so they possibly could be used where there is shallow underground water.

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‘Desert Museum’ Palo Verde Damaged by Wind

Leave a Comment / ornamental tree, repair, wind damage /

Q. I have a Desert Museum Palo Verde that was damaged during a windstorm. One of the branches blew off and damaged the trunk. It is an eyesore. Should I replace it? Palo verde is a rather soft tree particularly if you are in a hurry and want to grow it fast. Watering it like a mesic tree will speed its growth but could increase its potential for damage during strong winds. A. I would let the tree heal on its own but help it along its way. Healing takes two to three years if the tree is kept in good health. To do that, clean up the wound and apply management practices that encourage it to heal.  Sealing paints are a gimmick and don’t help the tree heal. In fact it can do just the opposite and prevent rapid healing. Don’t use any paint or “tree healer” as this was proven ineffective in past research and could actually slow the healing process. If you do paint the damaged area, use latex water-based paint. If there are any “splinters” resulting from the damage, remove them with a sanitized knife. Make the damage, and healthy areas surrounding it, as smooth as possible so the healing is faster and pleasant to look at. With that same knife remove the outer bark so that the edge is smooth and clean, and the damaged area is shaped like a vertical football. The damaged area will “compartmentalize” and the tree will “roll” over the area as it heals over the next couple of years. When the tree starts to grow this spring, make sure it gets adequate amounts of water and fertilizer. Good health practices help the tree to heal faster. To reattach or repair a limb split, or otherwise damaged area from a tree during a windstorm, is usually a lost cause. If done successfully the limb must be reattached, or repaired, within minutes or even seconds after it is severed or broken. Time is very important so that the damaged area doesn’t “dry out” before it is repaired.

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Strawberry Guava for Las Vegas?

Leave a Comment / Florida, freeze tolerance, Guava, soil amendments /

Q. I am interested in growing strawberry guava in Southwest Las Vegas and wish to know if these are good choices. Can you tell me what fruit and evergreen tree varieties have the best chance to survive in our desert? Strawberry guava is a guava with red fruit. It is cold or winter tender and should only be grown on the east side of a house or tall wall. The soil MUST be amended with compost.  It requires a lot of water (mesic) and can grow over ten feet tall. Here it is growing at our farm in the Philippines where it is warmer. Strawberry guava doesn’t taste like strawberries. A. Our desert can be a place to grow strawberry guava except for our cold winters and occasional snowfall. The fruit grows on new growth from a small tree, 10 to 20 feet tall. If they are kept warm or from freezing and planted in a part of the landscape that gets afternoon shade, then strawberry guava will work here.  During the very low winters of 1989 to 1990 it got from 10 to 15F but those are 25-to-50-year lows. So short term, temperatures of 25F or below is expected occasionally. Fully grown, they will survive freezing temperatures to about 25F for short periods of time. How to Grow It Here Its not easy or cheap. My suggestion, if you plan to grow them here, is to pick a non-windy place (windy locations make temperatures colder in my opinion) in your landscape. This protected location should get at least six hours of direct sunlight in the morning. Protect them from the wind with a constructed wind barrier. Not a solid wall. Solid walls create “dust devils”. Pick a location that is either on the east side or north side of a building or wall, not hotter locations found on the west or south sides.  Plant them at least five feet from a wall or building. Make sure the planting hole is about 3 to 4 feet wide and dug as deep as the roots. Amend the soil with compost or use composted soil when planting. Make sure the soil is wet, not dry. Plant in a hurry. Cover the soil with a 3-to-4-inch layer of wood chips when finished. Stake the tree after planting. Protect it from rabbits or other vermin if they are seen. Applied water should wet the soil to 18 inches deep to at least half the area under the tree canopy as it gets bigger. Avoid planting seeded types but instead pick pink or red varieties like ‘Homestead’, ‘Barbie Pink’, ‘Hong Kong Pink’, ‘Blitch’ and varieties recommended by the University of Florida that have proven successful there. Green varieties are picked before they are ripe and red or pink varieties are picked after they ripen. Guava is a climacteric fruit so it will ripen further after the fruit is hard but near ripe.

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Star Jasmine Needs Sun and Watered Like a Shrub

Leave a Comment / bare stems, Star Jasmine, yellowing /

Q. I am hoping you can tell me what is wrong with my “star jasmine”. These plants are approximately twenty years old. The wall they are growing on is north facing. I have pulled the rock mulch away from the base. I mix in compost to each plant every spring when I fertilize. Could it be the irrigation is too close to the trunk? Star jasmine is from the area of Japan. The great deserts of Japan…not!!! It is not a xeric plant and so it can get yellow, iron chlorosis, in rock. Plant it with compost in the soil and build up the organic content. A. Without looking at the pictures I was expecting them to be yellow. That’s usually what happens to star jasmine in rock landscapes. Your addition of compost to the soil is keeping them green and healthy. Bare wooden stems can sometimes happen when it is in poor health or covered with shady growth on top. Perhaps Watering too Often Bare stems on older growth can be a natural occurrence. I don’t think it is in your case. It is possible if the water applied is too close to the stems AND it is being applied too often then you can end up with bare stems. It is best if the water is applied at 12 to 18 inches from the trunk (stems, base) of the vine. Water, when it hits the soil, spreads out. In soils that are very sandy then this distance might be 12 inches from where it is applied. If the soil has a small amount of clay in it then the spread is about 18 inches from where it is applied. In soil with lots of clay (most of the soils in Las Vegas do not have that much clay) then water can spread out from where it was applied from 4 to 6 feet. A happy medium is 12 to 18 inches from the stems or trunk. Be careful of applying water too often. It can keep the soil wet too long. This can result in leaf drop followed by bare stems. It is always best on plants that have deeper roots (like your jasmine vine) to apply water less often. Vines like star jasmine are deeper-rooted, like medium sized shrubs. Water should wet the soil 12 to 18 inches deep each time is applied. Water your vines like they are medium sized shrubs. What to Do? What can you do with bare stems? Cut them back no closer than three or four inches and they will send out “suckers” and those suckers will fill in open spaces if the vine is alive. You may have to cut alot of stems back and start over if it is bad.

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