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Hibiscus Blooming but Leaves Too Small

2 Comments / how to grow hibiscus / xtremehorticulture

Q. My hibiscus plant, which I planted from a pot to my outdoor flower bed, is blooming like it should. The problem is, that the leaves are not getting any bigger than 1 – 1½” long and ¾” wide. The new leaves also only get to that size. I water and fertilize if with Miracle Grow regularly, but that does not help. Any suggestions? A. The appearance of plants will be different when growing in different climate zones. Appearance can also be impacted by your management practices. Let’s cover a few of these. Red hibiscus growing on our farm, Moca Family Farm, in the Philippines Climate and Microclimates. Plants growing under high light intensities will have a different appearance then plants growing under lower light intensities. The principal differences are in leaf size, color and thickness. Leaves growing under higher light intensities, provided they are getting enough water and nutrients, will be dark green, they will be smaller, thicker or tougher and develop a thicker waxy coating on the leaf surface. The same plant growing under lower light intensities will have larger and thinner leaves with a waxy coating that is not as thick. If light intensities get extremely high then we will see leaf discoloration, yellowing or bronzing, on some plants because the light intensity is actually damaging the leaves. If the same plant does not receive enough light then the plant will become “leggy” with large distances between the leaves and thin stems that will not support its own weight. The plant will become “floppy”. Our job as a manager of this plant is to find the right location in our landscape, the right microclimate, that will give it enough light so that it will flower and have an appearance close to what we expect. Because we are in a desert, Hibiscus might not look exactly the same as it does in semi tropical or tropical climates but we can approach that look if we are careful where we plant it. Fertilizer. The selection of the right type of fertilizer and amount of fertilizer will, to a large degree, influence the type of growth we get from a plant. We know for instance that phosphorus fertilizers are very important for flowering, fruiting, root development and production of oils in plants. If not enough phosphorus is present for the plant to use it will impact this type of growth. If too much is present, it can also impact growth of plants by “messing up” the soil chemistry. If fertilizers are applied to the soil, we generally do not need to apply phosphorus frequently. Nitrogen is a different animal. Nitrogen is important for developing dark green color in leaves and stems and for “pushing” new growth. It is important in producing good leaf size and in the number of leaves and supporting stems produced. The nitrogen in soils available to plants are in “salt” form. Applying too much nitrogen can result in leaf burning or scorching along the edges and even plant dieback or death if excessive amounts are applied. Unlike phosphorus, nitrogen is removed from the soil fairly quickly unless it is in organic form. The nitrogen will be depleted in 4 to 6 weeks through plant uptake and removal from the soil by the irrigation water and “evaporating” into the air. Organic nitrogen is removed much more slowly and gives the plants a “steady feeding” of nitrogen over a longer period of time. In your case you want to make sure that nitrogen is applied regularly through the growing season to maintain dark green color and “push” new growth. Combined with moderate amounts of shade, nitrogen will encourage more leaves and larger leaves. Soil. Organic matter such as compost mixed into the soil at the time of planting and applied at least annually to the surface of the soil surrounding the plant will encourage more leaf production and larger leaves on those plants which have it in their genetics to produce this kind of growth. I have seen this numerous times on a number of plants particularly in parts of the plants that are shaded such as lower leaves. What do you need to do? Understand that if your hibiscus is in a very hot, bright location that this location will limit the plants ability to produce larger leaves. Moderate amounts of shade will encourage larger leaf development, particularly in a microclimate that gets morning sun but afternoon shade. Get some compost and dig it into the soil surrounding the plant as much as you can. Apply about 1 inch of compost to the soil surface after you are finished and thoroughly wet the soil deeply immediately after you apply. At least once a year apply compost to the soil surface surrounding the plant and water it in thoroughly. Apply phosphorus either to the soil or to the foliage as a foliar spray at least once a year after it is finished flowering for the season. Apply high nitrogen fertilizers to the soil surrounding the plant in early spring, early summer and late summer. Winter tender plants should not be fertilized with high nitrogen fertilizers after August 1. The three overall factors that will determine the leaf size: what it’s capable of producing genetically (if you know this plant can produce much larger leaves but it is not doing it), soil improvement, and application of nitrogen fertilizers.

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Oleander Leaf Scorch Disease a Rarity in Las Vegas

Q. We are thinking of putting in a new oleander bush/tree. But we are concerned about oleander leaf scorch affecting our new plant in the near future. We’ve read where the disease has killed oleander in California and Arizona. Has it been found here in the Las Vegas and/or Nevada as a whole? If not here now, is it wise to put in a new plant? Oleander with leaf scorch A. I rarely see any problems on oleander here. Oleander leaf scorch usually occurs in Southern California and not in southern Nevada. I know our state plant pathologist has been watching for it here and is taken several samples looking for it. There has been some debate about whether this disease in oleander can be transferred to grapes and cause a similar disease and appearance called Pierce’s Disease. The researcher is pretty firm that it does not. For more information on oleander leaf scorch I would refer you to the University of California website. If you are convinced that your oleander may be diseased with leaf scorch, contact the Nevada State Department of Agriculture. Freeze damage of oleander and recovery in the spring Diseases are very rare but do happen occasionally. Nothing to worry about. Keep the plants healthy with plenty of water and mulch the soil with organic mulches when possible. Some oleanders are more tender during winter freezes than others. When oleanders become overgrown and woody, cut them within a couple of inches of the ground in the winter and let them grow back from these stumps.

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Salt Cedar Removal from Landscapes Is Difficult

Leave a Comment / controlling tamarisk, killing salt cedar, Removing salt cedar / xtremehorticulture

Q. What is the best way to remove Salt Cedar, mature trees and the seedlings that are sprouting all over the yard? Would appreciate any advice you might be able to offer. A. You should consider getting rid of it but I will warn you it will be difficult. Salt cedar, or tamarisk, produces hundreds if not thousands of seeds every year. The seeds will germinate easily even floating on water or submerged in flooded soils. Salt cedar is a problem because it uses so much water and kills other plants growing close to it by pulling salt out of the soil, concentrating it in its needle-like foliage and dropping this salt load on the soil surface. The salt concentrations are so high, very little will grow in these areas. The other problem is that it suckers easily from its roots so just cutting it down will cause it to sucker in many other places. The most effective way has been to cut it down as close to the soil as possible and apply weed killers to the fresh surface of the cut. Another method is to drill holes in the trunk close to the soil and inject weed killers into these fresh wounds. The two most effective weed killers have been Roundup (glyphosate) and Garlon (tyriclopyr). The label will tell you the concentration you should use. The best time for treatment is in the fall months just before plants are preparing for winter, not the spring. In our climate this would be October and perhaps early November. After the tree has been injected and begins to die, you will probably see suckers growing from the roots in a last ditch effort to stay alive. Cut these suckers close to the ground and daub on the fresh cut ends with the same solution. Do not make the mistake of thinking that a greater concentration of the chemical will give a better kill. Use the labeled concentrations. These were established by the manufacturer and tested in the field. Seeds from the mother plant may continue to germinate for a long time after the tree is dead and been removed. When these seedlings emerge from the soil, kill them immediately. They can grow 1 foot or more every month during summer. Their roots grew first before the top so it will be deep. All of these years I have been working near and around salt cedar and I have no pictures of it. If any of you have some that are yours, send it to me and I will post it here. More information about salts cedar and its removal

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Peach Tree Life Limited by Borers

Leave a Comment / why is my peach tree dying / xtremehorticulture

Q. I have a peach tree that has produced magnificent fruit for over 15 years- for the past two seasons I have seen no production or at best tiny fruit that doesn’t mature- I have studied your blog and believe that my tree has peach tree borer damage. I live in southern California- zone 9. Should I try to save the tree or is it a lost cause and if so what applications can I use to restore it? I prefer organic methods. A. I am more familiar with the problems in the Mojave Desert but I would probably agree with you that it is some type of borer. Peach trees can be fairly short-lived in many locale because of borers. This includes other countries I have visited. The borers are different but the result is the same. At our orchard in North Las Vegas peach trees that are 15 years old are getting up there in age and a 20 year old tree is old. All that being said you can always find someone who has a peach tree that is 40 years old but it is rare and they were lucky or possibly the variety but trees that old are usually not productive any more. I would remove it and replace it with another this fall if you can find a variety you like. If you are in a very temperate part of southern California like the San Diego area or along the coast you could do it any time. In the hot desert area, wait until it cools off.

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Cilantro, Parsley and Basil Are Easy to Grow in the Desert

Leave a Comment / how to go cilantro, How to grow basil, how to grow Italian parsley / xtremehorticulture

Q. Please, I would like to know what is the best way to grow Cilantro, Italian parsley and basil in Las Vegas. I have tried several times growing them in pots from small plants or directly transplanting them to the raised bed we have. I am not sure if I water them in excess or not enough but the leave start falling out or dry out. A. All three of these are pretty easy to grow here if you have prepared your soil adequately and growing them at the right time of year. All three can handle full sun but they should not be put into areas of the landscape that are extraordinarily hot due to reflected heat from walls in the late afternoon. Basil test plots in North Las Vegas. Here we grew 17 varieties of basil and all of them did well under drip irrigation. I have grown all three of them frequently and have had no problems with them except some insect management. Basil loves the heat and should not be put in the garden until temperatures start to warm up, perhaps late March or early April if temperatures are warm. They do not like cool temperatures below 55° F. Cilantro and Italian parsley also do very well here but prefer cooler temperatures of spring and fall rather than the heat of our summer. A great time to plant cilantro and Italian parsley is in the early fall or late summer when temperatures begin to cool off. Italian parsley growing in North Las Vegas with drip irrigation If we have a hard freeze you might lose them during the winter months but if winters are mild and you place them in a warm part of the landscape protected from wind they will probably survive the winter. After it gets established and growing well, basil can handle temperatures all the way down to freezing but nothing below freezing. Parsley Hamburg growing in North Las Vegas. The only problem I had with it was dodder one year. When temperatures get cold in the late fall and you fear a freeze, throw a light sheet or even better a crop cover over the top of them just before sundown when soils are still warm. This will protect them 5 to 6° F below their freezing point. Your basic elements of success in this order will be planting at the right time, soil preparation, watering correctly, protection from bugs and location in the yard for protection from cold and wind. Leaf cutter be damage to basil Insect problems, generally speaking, include aphids and “worms” which are larva of moths mostly. I would focus on for organic options; insecticidal soap, oils such as horticultural oil or Neem, Bt or Spinosad and a pyrethrum product for fast knockdown. I would use them in rotation as pests begin to appear in the spring and as needed. Leaf cutter bees can be a problem on basil but I do not recommend any insecticides. It is better to cover basil with insect netting or ignore it.

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Another African Sumac Dropping Leaves in Summer

Leave a Comment / Why is my African sumac dropping leaves / xtremehorticulture

Q. I have a concern about our 10 year old African Sumac. Is it normal for it to lose large amounts of leaves in the summer? There is new growth, but it is not full and bushy as others in the neighborhood. A. No, it is not. But be aware that African sumac is a very messy tree for a variety of reason. I have posted information on this on my blog. African sumac in bloom in February. Achooooo….. http://xtremehorticulture.blogspot.com/2014/08/african-sumac-can-be-messy-tr ee.html http://xtremehorticulture.blogspot.com/2011/07/african-sumac-and-leaf-drop.h tml http://xtremehorticulture.blogspot.com/2014/11/african-sumac-needs-more-wate r-as-it.html http://xtremehorticulture.blogspot.com/2014/08/african-sumac-with-curled-lea ves.html http://xtremehorticulture.blogspot.com/p/how-to-search-my-blog.html

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Rose Primer for the Desert

1 Comment / do roses grow in the desert, how to grow roses / xtremehorticulture

Hybrid Tea rose ‘Las Vegas’ Q. I enjoy your page in the RJ, but I cannot see that you ever write about ROSE BUSHES. We inherited these 14 year old, (estimate), bushes when we bought this house in 2011. I ask friends, that have roses, and up until this summer, used Lady Bugs, Rose food, have hosed out salts from the roots, etc. The bushes take up one side of the front of my walk way, plus in 3 other places, and it is important to me, that they look nice.Thank you for your thoughts on my problem. A. Thanks for asking that question. I seldom generate my own questions so I rely on the public to send these questions to me. It is my hope that people who read my blog and newspaper article will ask questions that many other people are also asking themselves. I seldom try to “second-guess” what people are thinking. Let’s cover some general tips on roses and this would be posted on my blog and an abbreviated form of it in my gardening column. There are two Rose Societies in the Las Vegas Valley; the long-standing Las Vegas Valley Rose Society and a second one which split from the original as the Las Vegas valley became larger, South Valley Rose Society Get information about the Las Vegas Rose Society Go to the South Valley Rose Society website I consider many of these members to be outstanding Rosarians and I defer to them and their expertise. However, I will give you my version of growing roses here in the eastern Mojave Desert. Roses do extremely well in our climate. The “winter” for roses is during the heat of the summer; June July and August. Expect that roses will look their worst in these months. The rest of the year Rosa canina, dog rose, used in Central Asia for its high Vitamin C content they do beautifully and are very prolific bloomers. If you want your roses to bloom during late December and January, plant them close to a south facing wall that throws radiant heat out during the winter. Our garden rose takes many different forms from miniatures to climbing roses to the garden rose in its many forms such as the Hybrid Teas, Floribundas, Grandiflora and the so-called shrub roses. Shrub roses is a catchall category for those that don’t fit anything else. All of them will grow in our climate but an excellent grower and hybridizer of roses, Go to the Weeks Roses website puts together a list of roses that do well in our desert climate and publishes it every year Go to Weeks Roses recommended roses for the desert If you are planning to grow roses, I would strongly suggest that you pay very close attention to your Rose selection by following lists such as these. These are solid recommendations. Rose ‘Nevada’ a semi-doubled shrub rose developed in 1927. Blah, Blah, Blah. Most of the roses that are popular among home gardeners are what we call “repeat bloomers”. Roses weren’t always like this. Roses grew in different places all over the world including the Americas but the ancestors of what we now recognize as a modern garden rose had its origins most likely in western China and Central Asia. These areas of the world are very dry. International traders like Marco Polo, before and after him, moved these roses all over the world including the Middle East, northern Africa Eastern Europe and Western Europe. Before and after these roses were moved internationally, horticulturists and gardeners began to breed them for different traits. The two traits that probably dominated most of the breeding early on was flower color and repeat blooming. Once the repeat bloomer discovered in China was identified, there was a scramble by many ancient Rose enthusiasts to “breed” this trait into the garden rose. Voilà. All of our popular garden roses now are repeat bloomers. Other traits popular were oil production and floral aroma which is tied very closely to the type of oils produced. Marco Polo trade routes from China Moving roses from dry Central Asia and western China to the wetter climates of Europe produced an increased number of disease and insect problems. We can see the reverse of this when we grow roses in desert climates. We see disease and insect problems are normally minimal so the need for spraying roses in our climate because of diseases and insects is small. Aphids on unopened rose flower buds Selection of roses for the home garden. Use a list like the one I talked about earlier to pick a variety that does best in our desert climate. Nearly all other varieties will do well but growing those selected for the desert that will tolerate the heat and our soils will do better than others. Straight phosphorus Planting roses. If you plant into native desert soil, blend this soil with an equal amount of good quality compost. If you are using a good quality soil mix, plant directly into this mix without amending the soil. Add a starter fertilizer high in phosphorus mixed into the backfill surrounding the roots at the time of planting. Always plant into a “wet” hole, never plant directly into dry soil or a dry soil mix. Wood chip mulch, not bark mulch, for soil improvement Always cover the surface of the soil with 3 to 4 inches of mulch that decomposes adding organic matter to the soil as it does. This type of mulch is a “wood chip mulch”, not a bark mulch or a rock mulch. If you must use a bark mulch, then use a wood chip mulch first and cover the surface last with bark mulch. Fertilizers. When first planting roses use a fertilizer high in phosphorus blended into the backfill at the time of planting. Or just use a straight phosphorus fertilizer instead. Once planted, focus on getting some size on the plant by using fertilizers high in nitrogen. Good

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Attention All Grade 3 Students Who Want to Garden!

Leave a Comment / ag in the classroom, gardening contest, third grade curriculum / xtremehorticulture

The Bonnie Plants Third Grade Cabbage Program Registration is open now and it is free! Gardening teaches kids where food comes from, healthy eating and heightens their engagement with nature. A great way to get kids started in the garden is the National Bonnie Plants Third Grade Cabbage Program, it’s free to any third grade classroom in the country (48 contiguous states), and kids love it! The program began in 1995 at Bonnie Plants headquarters in Alabama, by 2002; it grew by leaps and bounds and now includes 48 states! Bonnie Plants initiated the program with a mission to inspire a love of vegetable and herb gardening in young people. Each year, Bonnie trucks more than one million free O.S. Cross cabbage plants to 3rd grade classrooms across the country. Calling all Third Graders! Have you ever tried growing your own food right in your own backyard? Whether you’ve thought about it or not, you can do it, and the National Bonnie Plants Third Grade Cabbage Program will help you. Here’s how it works…. Every third grade classroom in the 48 contiguous states is invited to join this fun, free, colossal cabbage growing contest. Yes, it’s a National contest! Growing a cabbage provides third grade students with a chance to win a $1,000 scholarship from Bonnie Plants, plus statewide recognition. Bonnie Plants awards a scholarship to one winner from each state. Third Grade Teachers: If your third grade class isn’t already registered for this exciting program, it’s simple to get started. You can easily register your class online at www.bonnieplants.com. Just fill out the registration form and submit. Once registered, Bonnie Plants will truck, direct to your classroom, enough cabbage plants for each of your third grade students to take home and grow. Delivery date(s) are based on geographic region. The cabbage provided is an O.S. Cross; the “O.S.” stands for “oversized” and this variety can grow to be gigantic! In 8 to 10 weeks after planting, students should have a huge, healthy cabbage ready for harvest and program entry. To view past winners and learn more about the Bonnie Plants Cabbage Program contest visit www.bonnieplants.com and click on the “Cabbage Program” tab at top of screen. Green Earth Media Group Joan Casanova 203 292 8820 203 610 2069 (cell) [email protected]

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What’s Wrong with My Pampas Grass?

Leave a Comment / Center is dying out, how to prune, when to fertilize / xtremehorticulture

Q. My question is about our pampas grass which is now about six or seven years old. In the beginning the plumes were white, but now are brownish yellow. In fact, they look dirty. I notice too most of the plumes are coming on only half of the plant. Pampas grass flowering A. Pampas grass is native to the grasslands and plains of South America. It has evolved with fire which is a clue about how to manage it. In the wild, range fires every few years keep these things burned to the ground and renewed naturally. By the way, the standard size pampas grass is very large and should not be used in landscapes that do not have the room to support its growth. There are dwarf forms of this plant that would be more suitable and in a variety of colors. They are a pain in the neck to prune and some people burn them to the ground every three or four years where burning is permitted. If burning is not permitted, they may be cut to the ground and hauled off. This avoids the problems surrounding fire. Burning or pruning helps renew the plant and keeps its growth more evenly balanced. When pampas grass first blooms, the plumes may be an assortment of colors depending on the type of pampas grass. After a short time the flowers may begin to turn an off shade of the same color. Pampas grass continually puts on new growth from short rhizomes on the periphery of the plant. As it does this, the center may stop being very productive. In some cases parts of the plant may die as they get older, larger and overgrown. Giving the plant adequate water, fertilizer in early spring and pruning it properly should help quite a bit in maintaining good growth and color.

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Remove “Arms” Of Mediterranean Fan Palm To Make It More Open

Leave a Comment / How to prune Mediterranean fan Palm / xtremehorticulture

Q. We have seven Mediterranean fan palms in our yard, one of which has an “arm” which will eventually block easy access to walk around that side of the house. Is it harmful to the palm to cut off this arm? If not, is there a time of year that is best to do so? How many “arms” can this type of palm sustain? Is there a suggested maximum? Mediterranean fan Palm with a pruned canopy to make it more open A. Mediterranean fan palm is meant to be a clumping palm with many side shoots that makes a canopy which is a dense, half circle if it is left undisturbed. Many people will remove some more many of these “arms” to make it more open. In some cases I have seen all of them removed except for the middle one. You can cut them back to the ground or even below ground at their point of origin in the clump. In fact, that is the best way to do it. You can prune these palms nearly any time of the year but it is best to do it during warm weather so they have a chance to heal. Remove soil from that side and cut it off with a reciprocating saw or handsaw after the blade has been sanitized with alcohol or dilute concoction of 5% bleach and water. If using bleach, oil the blade afterwards. Replace the soil after a several days when the wound has healed. They are more visually appealing with an odd number of “arms” so three, five or seven going in different directions and with a balanced canopy is usually the best looking.

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